Rocket/CHANGELOG.md

# Version 0.5.0-rc.4 (Nov 1, 2023)

## Major Features and Improvements

  * Introduced [request connection upgrade APIs].

    The APIs allow responders to handle upgrade requests by [registering]
    [`IoHandler`]s for upgraded protocols. The [`IoHandler`] can perform raw
    byte I/O with the client. This functionality is used to implement WebSocket
    support by the newly introduced [`rocket_ws`] library.

  * Introduced WebSocket support: [`rocket_ws`].

    The newly introduced [`rocket_ws`] contrib library -- entirely external to
    Rocket itself -- provides complete, multi-modal support for interacting with
    clients over WebSockets. Modalities include async streams:

    ```rust
    #[get("/echo?compose")]
    fn echo_compose(ws: ws::WebSocket) -> ws::Stream!['static] {
        ws.stream(|io| io)
    }
    ```

    And generator syntax, among others:

    ```rust
    #[get("/echo?stream")]
    fn echo_stream(ws: ws::WebSocket) -> ws::Stream!['static] {
        ws::Stream! { ws =>
            for await message in ws {
                yield message?;
            }
        }
    }
    ```

[request connection upgrade APIs]: https://api.rocket.rs/v0.5-rc/rocket/struct.Response.html#upgrading
[`rocket_ws`]: https://api.rocket.rs/v0.5-rc/rocket_ws/
[registering]: https://api.rocket.rs/v0.5-rc/rocket/response/struct.Response.html#method.add_upgrade
[`IoHandler`]: https://api.rocket.rs/v0.5-rc/rocket/data/trait.IoHandler.html

## Breaking Changes

  * The types of responders in [`response::status`] were unified to all be of
    the form `Status<R>(R)`.

    Previously, some responders were of the form `Status<R>(Option<R>)`.

  * [Custom form errors] must now specify an associated `Status`.

    Change errors created as `ErrorKind(error)` to `ErrorKind(status, error)`.

  * [Route `Forward` outcomes] are now associated with a `Status`.

    This allows guards to determine which catcher will be invoked when all
    routes forward. All [`request::Outcome`] `Forward` values must be modified
    to include a `Status` hint.

  * `Outcome::Failure` was renamed to [`Outcome::Error`].

    This disambiguates the leading `F`s in `Failure` and `Forward`. In
    particular, generics of `E` and `F` now clearly correspond to `Error` and
    `Forward`, respectively.

  * The status codes used when built-in guards forward were changed.

    Previously, the `NotFound` status code was used to signal many kinds of
    recoverable, forwarding errors. This included validation errors, incorrect
    Content-Type errors, and more. This has been changed such that the status
    code used more closely matches the issue encountered.

    The net effect is that different error catchers will be invoked when
    built-in guards fail. The complete changes are:

    * Route parameter `FromParam` errors now forward as 422.
    * Query paramater errors now forward as 422.
    * Incorrect form content-type errors forwards as 413.
    * `&Host`, `&Accept`, `&ContentType`, `IpAddr`, and `SocketAddr` all forward
      with a 500.

  * [`IntoOutcome`] was overhauled to supplant methods now removed in `Outcome`.

    * `IntoOutcome::into_outcome()` is now `or_error()`.
    * `IntoOutcome` is implemented for all `Outcome` type aliases.
    * `Outcome::forward()` requires specifying a status code.
    * `Outcome::from()` and `Outcome::from_or_forward()` were removed.

      Use `responder.respond_to(req)` followed by a chaining of `.or_error()` or
      `.or_forward()`.

  * `Secure` cookie flags are set by default when serving over TLS.

  * Removal cookies now have `SameSite` set to `Lax`.

  * [`MediaType::JavaScript`] is now `text/javascript`.

[`response::status`]: https://api.rocket.rs/v0.5-rc/rocket/response/status/index.html
[Custom form errors]: https://api.rocket.rs/v0.5-rc/rocket/form/error/enum.ErrorKind.html#variant.Custom
[`request::Outcome`]: https://api.rocket.rs/v0.5-rc/rocket/request/type.Outcome.html#variant.Forward
[Route `Forward` outcomes]: https://api.rocket.rs/v0.5-rc/rocket/request/type.Outcome.html#variant.Forward
[`Outcome::Error`]: https://api.rocket.rs/v0.5-rc/rocket/outcome/enum.Outcome.html#variant.Error
[`IntoOutcome`]: https://api.rocket.rs/v0.5-rc/rocket/outcome/trait.IntoOutcome.html
[`MediaType::JavaScript`]: https://api.rocket.rs/v0.5-rc/rocket/http/struct.MediaType.html#associatedconstant.JavaScript

## General Improvements

  * [`rocket_db_pools`] gained support for [`diesel-async`].
  * Added [`TempFile::open()`] to stream `TempFile` data.
  * mTLS certificates can now be set on local requests via
    [`LocalRequest::identity()`].
  * Added [`Error::pretty_print()`] for pretty-printing errors like Rocket.
  * The TLS example now includes an HTTP to HTTPS redirection fairing.
  * When data limits are reached, warnings are logged.
  * A warning is emitted when `String` is used as a route parameter.
  * Configuration provenance information is logged under the `debug` log level.
  * `template_dir` as recognized by `rocket_dyn_templates` is more reliably
    interpreted.
  * Logging of `Outcome`s now includes the relevant status code.

[`diesel-async`]: https://api.rocket.rs/v0.5-rc/rocket_db_pools/index.html#diesel-v2
[`LocalRequest::identity()`]: https://api.rocket.rs/v0.5-rc/rocket/local/blocking/struct.LocalRequest.html#method.identity
[`TempFile::open()`]: https://api.rocket.rs/v0.5-rc/rocket/fs/enum.TempFile.html#method.open
[`Error::pretty_print()`]: https://api.rocket.rs/v0.5-rc/rocket/struct.Error.html#method.pretty_print

### Known Media Types

  * The `.mjs` extension is now recognized as JavaScript.
  * '.exe', '.iso', '.dmg' are marked as known extensions.

### Trait Implementations

  * Implemented `De(Serialize)` for `Status`.

### Updated Dependencies

  * `rustls` to 0.21.
  * `tokio-rustls` to 0.24.
  * `state` to 0.21.
  * `sqlx` to 0.7.
  * `notify` to 6.
  * `indexmap` to 2.
  * `cookie` to 0.18.

### Documentation

  * Driver versions in `db_pools` were fixed and updated.
  * Added details on using `Status` as a field in a derived `Responder`.
  * All built-in data guards are now properly documented.
  * Further details on deriving `UriDisplay` were added.
  * The guide now includes notes on enabling crate features when needed.

## Infrastructure

  * The CI now frees disk space before proceeding to avoid out-of-disk errors.
  * `Span::mixed_site()` is used in codegen to reduce errant `clippy` warnings.
  * All workspaces now use `resolver = 2`.

# Version 0.5.0-rc.3 (Mar 23, 2023)

## Major Features and Improvements

  * Added a [`max_blocking`] configuration parameter.

    The parameter sets a limit on the number of threads used by blocking tasks.

  * Added an [`ip_header`] "real IP" header configuration parameter.

    The parameter allows modifying the header that Rocket attempts to use to retrieve the "real IP"
    address of the client via `Request` methods like [`Request::client_ip()`]. Additionally, the
    change allows disabling the use of any such header entirely.

  * A [`pool()`] method is emitted by [`rocket_sync_db_pools`] for code-generated pools.

    The method returns an opaque reference to a type that can be used to retrieve pooled connections
    outside of a request handling context.

  * Raw binary form field data can be retrieved using the `&[u8]` form guard.

  * Data guards are now eligible [sentinels].

## General Improvements

  * Final launch messages are now _always_ logged, irrespective of profile.
  * Only functions that return `Rocket<Build>` are now `#[must_use]`, not all `Rocket<P>`.
  * Fixed mismatched form field names in errors under certain conditions in [`FromForm`] derive.
  * The [`FromForm`] derive now collects _all_ errors that occur.
  * Data pools are now gracefully shutdown in [`rocket_sync_db_pools`].
  * Added [`Metadata::render()`] in [`rocket_dyn_templates`] for direct template rendering.
  * Rocket salvages more information from malformed requests for error catchers.
  * The `cookie` `secure` feature is now properly conditionally enabled.
  * Data before encapsulation boundaries in TLS keys is allowed and ignored.
  * Support for TLS keys in SEC1 format was added.
  * Rocket now warns when a known secret key is configured.
  * A panic that could occur on shutdown in `rocket_sync_db_pools` was fixed.

### Known Media Types

  - Added `MP3`: `audio/mpeg`.
  - Added `CBZ`: `application/vnd.comicbook+zip`, extension `.cbz`.
  - Added `CBR`: `application/vnd.comicbook-rar`, extension `.cbr`.
  - Added `RAR`: `application/vnd.rar`, extension `.rar`.
  - Added `EPUB`: `application/epub+zip`, extension `.epub`.
  - Added `OPF`: `application/oebps-package+xml`, extension `.opf`.
  - Added `XHTML`: `application/xhtml+xml`, extension `.xhtml`.

### Trait Implementations

  * Implemented `Responder` for `Box<T: Responder + Sized>`.
  * Implemented `FromForm` for `Arc<T>`.
  * Implemented `Fairing` for `Arc<dyn Fairing>`.

### Updated Dependencies

  * Updated `syn` to `2`.
  * Updated `diesel` to `2.0`.
  * Updated `sqlx` to `0.6`.
  * Updated `notify` to `5.0`.
  * Updated `criterion` to `0.4`.
  * Updated `deadpool-redis` to `0.11`.
  * Updated `normpath` from to `1`.
  * Updated `cookie` to `0.17`.
  * Replaced `atty` with `is-terminal`.

## Infrastructure

  * UI tests are now allowed to fail by the CI to avoid false negatives.
  * Fixed many typos, errors, and broken links throughout docs and examples.
  * The GitHub CI workflow was updated to use maintained actions.

[`Metadata::render()`]: https://api.rocket.rs/v0.5-rc/rocket_dyn_templates/struct.Metadata.html#method.render
[`pool()`]: https://api.rocket.rs/v0.5-rc/rocket_sync_db_pools/example/struct.ExampleDb.html#method.pool
[`Request::client_ip()`]: https://api.rocket.rs/v0.5-rc/rocket/request/struct.Request.html#method.client_ip
[`max_blocking`]: https://api.rocket.rs/v0.5-rc/rocket/struct.Config.html#structfield.max_blocking
[`ip_header`]: https://api.rocket.rs/v0.5-rc/rocket/struct.Config.html#structfield.ip_header

# Version 0.5.0-rc.2 (May 09, 2022)

## Major Features and Improvements

  * Introduced [`rocket_db_pools`] for asynchronous database pooling.
  * Introduced support for [mutual TLS] and client [`Certificate`]s.
  * Added a [`local_cache_once!`] macro for request-local storage.
  * Added a [v0.4 to v0.5 migration guide] and [FAQ] to Rocket's website.
  * Introduced [shutdown fairings].

## Breaking Changes

  * `Hash` `impl`s for `MediaType` and `ContentType` no longer consider media type parameters.
  * TLS config values are only available when the `tls` feature is enabled.
  * [`MediaType::with_params()`] and [`ContentType::with_params()`] are now builder methods.
  * Content-Type [`content`] responder type names are now prefixed with `Raw`.
  * The `content::Plain` responder is now called `content::RawText`.
  * The `content::Custom<T>` responder was removed in favor of [`(ContentType, T)`].
  * TLS config structs are now only available when the `tls` feature is enabled.
  * Removed `CookieJar::get_private_pending()` in favor of [`CookieJar::get_pending()`].
  * The [`local_cache!`] macro accepts fewer types. Use [`local_cache_once!`] as appropriate.
  * When requested, the `FromForm` implementations of `Vec` and `Map`s are now properly lenient.
  * To concord with browsers, the `[` and `]` characters are now accepted in URI paths.
  * The `[` and `]` characters are no longer encoded by [`uri!`].
  * [`Rocket::launch()`] allows `Rocket` recovery by returning the instance after shutdown.
  * `ErrorKind::Runtime` was removed; [`ErrorKind::Shutdown`] was added.

## General Improvements

  * [`Rocket`] is now `#[must_use]`.
  * Support for HTTP/2 can be disabled by disabling the default `http2` crate feature.
  * Added [`rocket::execute()`] for executing Rocket's `launch()` future.
  * Added the [`context!`] macro to [`rocket_dyn_templates`] for ad-hoc template contexts.
  * The `time` crate is re-exported from the crate root.
  * The `FromForm`, `Responder`, and `UriDisplay` derives now fully support generics.
  * Added helper functions to `serde` submodules.
  * The [`Shield`] HSTS preload header now includes `includeSubdomains`.
  * Logging ignores `write!` errors if `stdout` disappears, preventing panics.
  * Added [`Client::terminate()`] to run graceful shutdown in testing.
  * Shutdown now terminates the `async` runtime, never the process.

### HTTP

  * Introduced [`Host`] and the [`&Host`] request guard.
  * Added `Markdown` (`text/markdown`) as a known media type.
  * Added [`RawStr::percent_encode_bytes()`].
  * `NODELAY` is now enabled on all connections by default.
  * The TLS implementation handles handshakes off the main task, improving DoS resistance.

### Request

  * Added [`Request::host()`] to retrieve the client-requested host.

### Trait Implementations

  * `Arc<T>`, `Box<T>` where `T: Responder` now implement `Responder`.
  * [`Method`] implements `Serialize` and `Deserialize`.
  * [`MediaType`] and [`ContentType`] implement `Eq`.

### Updated Dependencies

  * The `time` dependency was updated to `0.3`.
  * The `handlebars` dependency was updated to `4.0`.
  * The `memcache` dependency was updated to `0.16`.
  * The `rustls` dependency was updated to `0.20`.

## Infrastructure

  * Rocket now uses the 2021 edition of Rust.

[`(ContentType, T)`]: https://api.rocket.rs/v0.5-rc/rocket/response/content/index.html#usage
[v0.4 to v0.5 migration guide]: https://rocket.rs/v0.5-rc/guide/upgrading/
[FAQ]: https://rocket.rs/v0.5-rc/guide/faq/
[`Rocket::launch()`]: https://api.rocket.rs/v0.5-rc/rocket/struct.Rocket.html#method.launch
[`ErrorKind::Shutdown`]: https://api.rocket.rs/v0.5-rc/rocket/error/enum.ErrorKind.html#variant.Shutdown
[shutdown fairings]: https://api.rocket.rs/v0.5-rc/rocket/fairing/trait.Fairing.html#shutdown
[`Client::terminate()`]: https://api.rocket.rs/v0.5-rc/rocket/local/blocking/struct.Client.html#method.terminate
[`rocket::execute()`]: https://api.rocket.rs/v0.5-rc/rocket/fn.execute.html
[`CookieJar::get_pending()`]: https://api.rocket.rs/v0.5-rc/rocket/http/struct.CookieJar.html#method.get_pending

# Version 0.5.0-rc.1 (Jun 09, 2021)

## Major Features and Improvements

This release introduces the following major features and improvements:

  * Support for [compilation on Rust's stable] release channel.
  * A rewritten, fully asynchronous core with support for [`async`/`await`].
  * [Feature-complete forms support] including multipart, collections, [ad-hoc validation], and
    [context](https://rocket.rs/v0.5-rc/guide/requests/#context).
  * [Sentinels]: automatic verification of application state at start-up to prevent runtime errors.
  * [Graceful shutdown] with configurable signaling, grace periods, notification via [`Shutdown`].
  * An entirely new, flexible and robust [configuration system] based on [Figment].
  * Typed [asynchronous streams] and [Server-Sent Events] with generator syntax.
  * Automatic support for HTTP/2 including `h2` ALPN.
  * Graduation of `json`, `msgpack`, and `uuid` `rocket_contrib` [features into core].
  * An automatically enabled [`Shield`]: security and privacy headers for all responses.
  * Type-system enforced [incoming data limits] to mitigate memory-based DoS attacks.
  * Compile-time URI literals via a fully revamped [`uri!`] macro.
  * Full support for [UTF-8 characters] in routes and catchers.
  * Precise detection of unmanaged state and missing database, template fairings with [sentinels].
  * Typed [build phases] with strict application-level guarantees.
  * [Ignorable segments]: wildcard route matching with no typing restrictions.
  * First-class [support for `serde`] for built-in guards and types.
  * New application launch attributes:
    [`#[launch]`](https://api.rocket.rs/v0.5-rc/rocket/attr.launch.html) and
    [`#[rocket::main]`](https://api.rocket.rs/v0.5-rc/rocket/attr.main.html).
  * [Default catchers] via `#[catch(default)]`, which handle _any_ status code.
  * [Catcher scoping] to narrow the scope of a catcher to a URI prefix.
  * Built-in libraries and support for [asynchronous testing].
  * A [`TempFile`] data and form guard for automatic uploading to a temporary file.
  * A [`Capped<T>`] data and form guard which enables detecting truncation due to data limits.
  * Support for dynamic and static prefixing and suffixing of route URIs in [`uri!`].
  * Support for custom config profiles and [automatic typed config extraction].
  * Rewritten, zero-copy, RFC compliant URI parsers with support for URI-[`Reference`]s.
  * Multi-segment parameters (`<param..>`) which match _zero_ segments.
  * A [`request::local_cache!`] macro for request-local storage of non-uniquely typed values.
  * A [`CookieJar`] without "one-at-a-time" limitations.
  * [Singleton fairings] with replacement and guaranteed uniqueness.
  * [Data limit declaration in SI units]: "2 MiB", `2.mebibytes()`.
  * Optimistic responding even when data is left unread or limits are exceeded.
  * Fully decoded borrowed strings as dynamic parameters, form and data guards.
  * Borrowed byte slices as data and form guards.
  * Fail-fast behavior for [misconfigured secrets], file serving paths.
  * Support for generics and custom generic bounds in
    [`#[derive(Responder)]`](https://api.rocket.rs/v0.5-rc/rocket/derive.Responder.html).
  * [Default ranking colors], which prevent more routing collisions automatically.
  * Improved error logging with suggestions when common errors are detected.
  * Completely rewritten examples including a new real-time [`chat`] application.

## Support for Rust Stable

As a result of support for Rust stable (Rust 2021 Edition and beyond), the
`#![feature(..)]` crate attribute is no longer required for Rocket applications.
The complete canonical example with a single `hello` route becomes:

```rust
#[macro_use] extern crate rocket;

#[get("/<name>/<age>")]
fn hello(name: &str, age: u8) -> String {
    format!("Hello, {} year old named {}!", age, name)
}

#[launch]
fn rocket() -> _ {
    rocket::build().mount("/hello", routes![hello])
}
```

<details>
  <summary>See a <code>diff</code> of the changes from v0.4.</summary>

```diff
- #![feature(proc_macro_hygiene, decl_macro)]
-
 #[macro_use] extern crate rocket;

 #[get("/<name>/<age>")]
- fn hello(name: String, age: u8) -> String {
+ fn hello(name: &str, age: u8) -> String {
     format!("Hello, {} year old named {}!", age, name)
}

- fn main() {
-     rocket::ignite().mount("/hello", routes![hello]).launch();
- }
+ #[launch]
+ fn rocket() -> _ {
+     rocket::build().mount("/hello", routes![hello])
+ }
```

</details>

## Breaking Changes

This release includes many breaking changes. The most significant changes are listed below.

### Silent Changes

These changes are invisible to the compiler and will _not_ yield errors or warnings at compile-time.
We **strongly** advise all application authors to review this list carefully.

  * Blocking I/O (long running compute, synchronous `sleep()`, `Mutex`, `RwLock`, etc.) may prevent
    the server from making progress and should be avoided, replaced with an `async` variant, or
    performed in a worker thread. This is a consequence of Rust's cooperative `async` multitasking.
    For details, see the new [multitasking] section of the guide.
  * `ROCKET_ENV` is now `ROCKET_PROFILE`. A warning is emitted a launch time if the former is set.
  * The default profile for debug builds is now `debug`, not `dev`.
  * The default profile for release builds is now `release`, not `prod`.
  * `ROCKET_LOG` is now `ROCKET_LOG_LEVEL`. A warning is emitted a launch time if the former is set.
  * `ROCKET_ADDRESS` accepts only IP addresses, no longer resolves hostnames like `localhost`.
  * `ROCKET_CLI_COLORS` accepts booleans `true`, `false` in place of strings `"on"`, `"off"`.
  * It is a launch-time error if `secrets` is enabled in non-`debug` profiles without a configured
    `secret_key`.
  * A misconfigured `template_dir` is reported as an error at launch time.
  * [`FileServer::new()`] fails immediately if the provided directory does not exist.
  * Catcher collisions result in a launch failure as opposed to a warning.
  * Default ranks now range from `-12` to `-1`. There is no breaking change if only code generated
    routes are used. Manually configured routes with negative ranks may collide or be considered in
    a different order than before.
  * The order of execution of path and query guards relative to each other is now unspecified.
  * URIs beginning with `:` are properly recognized as invalid and rejected.
  * URI normalization now normalizes the query part as well.
  * The `Segments` iterator now returns percent-decoded `&str`s.
  * Forms are now parsed leniently by the [`Form` guard]. Use [`Strict`] for the previous behavior.
  * The `Option<T>` form guard defaults to `None` instead of the default value for `T`.
  * When data limits are exceeded, a `413 Payload Too Large` status is returned to the client.
  * The default catcher now returns JSON when the client indicates preference via the `Accept`
    header.
  * Empty boolean form values parse as `true`: the query string `?f` is the same as `?f=true`.
  * [`Created<R>`] does not automatically send an `ETag` header if `R: Hash`. Use
    [`Created::tagged_body`] instead.
  * `FileServer` now forwards when a file is not found instead of failing with `404 Not Found`.
  * [`Shield`] is enabled by default. You may need to disable or change policies if your application
    depends on typically insecure browser features or if you wish to opt-in to different policies
    than the defaults.
  * [`CookieJar`] `get()`s do not return cookies added during request handling. See
    [`CookieJar`#pending].

### Contrib Graduation

  * The `rocket_contrib` crate has been deprecated and should no longer be used.
  * Several features previously in `rocket_contrib` were merged into `rocket` itself:
    * `json`, `msgpack`, and `uuid` are now [features of `rocket`].
    * Moved `rocket_contrib::json` to [`rocket::serde::json`].
    * Moved `rocket_contrib::msgpack` to [`rocket::serde::msgpack`].
    * Moved `rocket_contrib::uuid` to [`rocket::serde::uuid`].
    * Moved `rocket_contrib::helmet` to [`rocket::shield`]. [`Shield`] is enabled by default.
    * Moved `rocket_contrib::serve` to [`rocket::fs`], `StaticFiles` to [`rocket::fs::FileServer`].
    * Removed the now unnecessary `Uuid` and `JsonValue` wrapper types.
    * Removed headers in `Shield` that are no longer respected by browsers.
  * The remaining features from `rocket_contrib` are now provided by separate crates:
    * Replaced `rocket_contrib::templates` with [`rocket_dyn_templates`].
    * Replaced `rocket_contrib::databases` with [`rocket_sync_db_pools`] and [`rocket_db_pools`].
    * These crates are versioned and released independently of `rocket`.
    * `rocket_contrib::databases::DbError` is now `rocket_sync_db_pools::Error`.
    * Removed `redis`, `mongodb`, and `mysql` integrations which have upstream `async` drivers.
    * The [`#[database]`](https://api.rocket.rs/v0.5-rc/rocket_sync_db_pools/attr.database.html)
      attribute generates an [`async run()`] method instead of `Deref` implementations.

### General

  * [`Rocket`] is now generic over a [phase] marker:
    * APIs operate on `Rocket<Build>`, `Rocket<Ignite>`, `Rocket<Orbit>`, or `Rocket<P: Phase>` as
      needed.
    * The phase marker statically enforces state transitions in `Build`, `Ignite`, `Orbit` order.
    * `rocket::ignite()` is now [`rocket::build()`], returns a `Rocket<Build>`.
    * [`Rocket::ignite()`] transitions to the `Ignite` phase. This is run automatically on launch as
      needed.
    * Ignition finalizes configuration, runs `ignite` fairings, and verifies [sentinels].
    * [`Rocket::launch()`] transitions into the `Orbit` phase and starts the server.
    * Methods like [`Request::rocket()`] that refer to a live Rocket instance return an
      `&Rocket<Orbit>`.
  * [Fairings] have been reorganized and restructured for `async`:
    * Replaced `attach` fairings with `ignite` fairings. Unlike `attach` fairings, which ran
      immediately at the time of attachment, `ignite` fairings are run when transitioning into the
      `Ignite` phase.
    * Replaced `launch` fairings with `liftoff` fairings. `liftoff` fairings are always run, even in
      local clients, after the server begins listening and the concrete port is known.
  * Introduced a new [configuration system] based on [Figment]:
    * The concept of "environments" is replaced with "profiles".
    * `ROCKET_ENV` is superseded by `ROCKET_PROFILE`.
    * `ROCKET_LOG` is superseded by `ROCKET_LOG_LEVEL`.
    * Profile names can now be arbitrarily chosen. The `dev`, `stage`, and `prod` profiles carry no
      special meaning.
    * The `debug` and `release` profiles are the default profiles for the debug and release
      compilation profiles.
    * A new specially recognized `default` profile specifies defaults for all profiles.
    * The `global` profile has highest precedence, followed by the selected profile, followed by
      `default`.
    * Added support for limits specified in SI units: "1 MiB".
    * Renamed `LoggingLevel` to [`LogLevel`].
    * Inlined error variants into the [`Error`] structure.
    * Changed the type of `workers` to `usize` from `u16`.
    * Changed accepted values for `keep_alive`: it is disabled with `0`, not `false` or `off`.
    * Disabled the `secrets` feature (for private cookies) by default.
    * Removed APIs related to "extras". Typed values can be extracted from the configured `Figment`.
    * Removed `ConfigBuilder`: all fields of [`Config`] are public with constructors for each field
      type.
  * Many functions, traits, and trait bounds have been modified for `async`:
    * [`FromRequest`], [`Fairing`], [`catcher::Handler`], [`route::Handler`], and [`FromData`] use
      `#[async_trait]`.
    * [`NamedFile::open`] is now an `async` function.
    * Added [`Request::local_cache_async()`] for use in async request guards.
    * Unsized `Response` bodies must be [`AsyncRead`] instead of `Read`.
    * Automatically sized `Response` bodies must be [`AsyncSeek`] instead of `Seek`.
    * The `local` module is split into two: [`rocket::local::asynchronous`] and
      [`rocket::local::blocking`].
  * Functionality and features requiring Rust nightly were removed:
    * Removed the `Try` implementation on [`Outcome`] which allowed using `?` with `Outcome`s. The
      recommended replacement is the [`rocket::outcome::try_outcome!`] macro or the various
      combinator functions on `Outcome`.
    * [`Result<T, E>` implements `Responder`] only when both `T` and `E` implement `Responder`. The
      new [`Debug`] wrapping responder replaces `Result<T: Responder, E: Debug>`.
    * APIs which used the `!` type to now use [`std::convert::Infallible`].
  * [`Rocket::register()`] now takes a base path to scope catchers under as its first argument.
  * `ErrorKind::Collision` has been renamed to [`ErrorKind::Collisions`].

[phase]: https://api.rocket.rs/v0.5-rc/rocket/struct.Rocket.html#phases

### Routing and URIs

  * In `#[route(GET, path = "...")]`, `path` is now `uri`: `#[route(GET, uri = "...")]`.
  * Multi-segment paths (`/<p..>`) now match _zero_ or more segments.
  * Codegen improvements preclude identically named routes and modules in the same namespace.
  * A route URI like (`/<a>/<p..>`) now collides with (`/<a>`), requires a `rank` to resolve.
  * All catcher related types and traits moved to [`rocket::catcher`].
  * All route related types and traits moved to [`rocket::route`].
  * URI formatting types and traits moved to [`rocket::http::uri::fmt`].
  * `T` no longer converts to `Option<T>` or `Result<T, _>` for [`uri!`] query parameters.
  * For optional query parameters, [`uri!`] requires using a wrapped value or `_`.
  * `&RawStr` no longer implements `FromParam`: use `&str` instead.
  * Percent-decoding is performed before calling `FromParam` implementations.
  * `RawStr::url_decode()` and `RawStr::url_decode_lossy()` allocate as necessary, return `Cow`.
  * `RawStr::from_str()` was replaced with `RawStr::new()`.
  * `Origin::segments()` was replaced with `Origin.path().segments()`.
  * `Origin::path()` and `Origin::query()` return `&RawStr` instead of `&str`.
  * The type of `Route::name` is now `Option<Cow<'static, str>>`.
  * `Route::set_uri` was replaced with [`Route::map_base()`].
  * `Route::uri()` returns a new [`RouteUri`] type.
  * `Route::base` was removed in favor of `Route.uri().base()`.

[`RouteUri`]: https://api.rocket.rs/v0.5-rc/rocket/route/struct.RouteUri.html

### Data and Forms

  * `Data` now has a lifetime: `Data<'r>`.
  * [`Data::open()`] indelibly requires a data limit.
  * Removed `FromDataSimple`. Use [`FromData`] and [`local_cache!`] or [`local_cache_once!`].
  * All [`DataStream`] APIs require limits and return [`Capped<T>`] types.
  * Form types and traits were moved from `rocket::request` to [`rocket::form`].
  * Removed `FromQuery`. Dynamic query parameters (`#[get("/?<param>")]`) use [`FromForm`] instead.
  * Replaced `FromFormValue` with [`FromFormField`]. All `T: FromFormField` implement `FromForm`.
  * Form field values are percent-decoded before calling [`FromFormField`] implementations.
  * Renamed the `#[form(field = ...)]` attribute to `#[field(name = ...)]`.

### Request Guards

  * Renamed `Cookies` to [`CookieJar`]. Its methods take `&self`.
  * Renamed `Flash.name` to `Flash.kind`, `Flash.msg` to `Flash.message`.
  * Replaced `Request::get_param()` with `Request::param()`.
  * Replaced `Request::get_segments()` to `Request::segments()`.
  * Replaced `Request::get_query_value()` with `Request::query_value()`.
  * Replaced `Segments::into_path_buf()` with `Segments::to_path_buf()`.
  * Replaced `Segments` and `QuerySegments` with [`Segments<Path>` and `Segments<Query>`].
  * [`Flash`] constructors to take `Into<String>` instead of `AsRef<str>`.
  * The `State<'_, T>` request guard is now `&State<T>`.
  * Removed a lifetime from [`FromRequest`]: `FromRequest<'r>`.
  * Removed a lifetime from [`FlashMessage`]: `FlashMessage<'_>`.
  * Removed all `State` reexports except [`rocket::State`].

### Responders

  * Moved `NamedFile` to `rocket::fs::NamedFile`
  * Replaced `Content` with `content::Custom`.
  * `Response::body` and `Response::body_mut` are now infallible methods.
  * Renamed `ResponseBuilder` to `Builder`.
  * Removed direct `Response` body reading methods. Use methods on `r.body_mut()` instead.
  * Removed inaccurate "chunked body" types and variants.
  * Removed `Responder` `impl` for `Response`. Prefer custom responders with `#[derive(Responder)]`.
  * Removed the unused reason phrase from `Status`.

## General Improvements

In addition to new features and major improvements, Rocket saw the following improvements:

### General

  * Added support for [raw identifiers] in the `FromForm` derive, `#[route]` macros, and `uri!`.
  * Added support for uncased derived form fields: `#[field(name = uncased(...))]`.
  * Added support for [default form field values]: `#[field(default = expr())]`.
  * Added support for multiple `#[field]` attributes on struct fields.
  * Added support for base16-encoded (a.k.a. hex-encoded) secret keys.
  * Added [`Config::ident`] for configuring or removing the global `Server` header.
  * Added [`Rocket::figment()`] and [`Rocket::catchers()`].
  * Added [`LocalRequest::json()`] and [`LocalResponse::json()`].
  * Added [`LocalRequest::msgpack()`] and [`LocalResponse::msgpack()`].
  * Added support for `use m::route; routes![route]` instead of needing `routes![m::route]`.
  * Added support for [hierarchical data limits]: a limit of `a/b/c` falls back to `a/b` then `a`.
  * Added [`LocalRequest::inner_mut()`]. `LocalRequest` implements `DerefMut` to `Request`.
  * Added support for ECDSA and EdDSA TLS keys.
  * Added associated constants in `Config` for all config parameter names.
  * Added `ErrorKind::Config` to represent errors in configuration at runtime.
  * Added `rocket::fairing::Result` type alias, returned by `Fairing::on_ignite()`.
  * All guard failures are logged at runtime.
  * `Rocket::mount()` now accepts a base value of any type that implements `TryInto<Origin<'_>>`.
  * The default error catcher's HTML has been compacted.
  * The default error catcher returns JSON if requested by the client.
  * Panics in routes or catchers are caught and forwarded to `500` error catcher.
  * A detailed warning is emitted if a route or catcher panics.
  * Emoji characters are no longer output on Windows.
  * Fixed [`Error`] to not panic if a panic is already in progress.
  * Introduced [`Reference`] and [`Asterisk`] URI types.
  * Added support to [`UriDisplayQuery`] for C-like enums.
  * The [`UriDisplayQuery`] derive now recognizes the `#[field]` attribute for field renaming.
  * `Client` method builders accept `TryInto<Origin>` allowing a `uri!()` to be used directly.
  * [`Redirect`] now accepts a `TryFrom<Reference>`, allowing fragment parts.

### HTTP

  * Added support for HTTP/2, enabled by default via the `http2` crate feature.
  * Added AVIF (`image/avif`) as a known media type.
  * Added `EventStream` (`text/event-stream`) as a known media type.
  * Added a `const` constructor for `MediaType`.
  * Added aliases `Text`, `Bytes` for the `Plain`, `Binary` media types, respectively.
  * Introduced [`RawStrBuf`], an owned `RawStr`.
  * Added many new "pattern" methods to [`RawStr`].
  * Added [`RawStr::percent_encode()`] and [`RawStr::strip()`].
  * Added support for unencoded query characters in URIs that are frequently sent by browsers.

### Request

  * Added support for all UTF-8 characters in route paths.
  * Added support for percent-encoded `:` in socket or IP address values in [`FromFormValue`].
  * Added [`Request::rocket()`] to access the active `Rocket` instance.
  * `Request::uri()` now returns an `&Origin<'r>` instead of `&Origin<'_>`.
  * `Request::accept()`, `Request::content_type()` reflect changes to `Accept`, `Content-Type`.
  * `Json<T>`, `MsgPack<T>` accept `T: Deserialize`, not only `T: DeserializeOwned`.
  * Diesel SQLite connections in `rocket_sync_db_pools` use better defaults.
  * The default number of workers for synchronous database pools is now `workers * 4`.

### Response

  * Added [`Template::try_custom()`] for fallible template engine customization.
  * Manually registered templates can now be rendered with `Template::render()`.
  * Added support for the `X-DNS-Prefetch-Control` header to `Shield`.
  * Added support for manually-set `expires` values for private cookies.
  * Added support for type generics and custom generic bounds to
    [`#[derive(Responder)]`](https://api.rocket.rs/v0.5-rc/rocket/derive.Responder.html).
  * The `Server` header is only set if one isn't already set.
  * Accurate `Content-Length` headers are sent even for partially read `Body`s.

### Trait Implementations

  * Implemented `Clone` for `State`.
  * Implemented `Copy` and `Clone` for `fairing::Info`.
  * Implemented `Debug` for `Rocket` and `Client`.
  * Implemented `Default` for `Status` (returns `Status::Ok`).
  * Implemented `PartialEq`, `Eq`, `Hash`, `PartialOrd`, and `Ord` for `Status`.
  * Implemented `Eq`, `Hash`, and `PartialEq<&str>` for `Origin`.
  * Implemented `PartialEq<Cow<'_, RawStr>>>` for `RawStr`.
  * Implemented `std::error::Error` for `Error`.
  * Implemented `Deref` and `DerefMut` for `LocalRequest` (to `Request`).
  * Implemented `DerefMut` for `Form`, `LenientForm`.
  * Implemented `From<T>` for `Json<T>`, `MsgPack<T>`.
  * Implemented `TryFrom<String>` and `TryFrom<&str>` for `Origin`.
  * Implemented `TryFrom<Uri>` for each of the specific URI variants.
  * Implemented `FromRequest` for `&Config`.
  * Implemented `FromRequest` for `IpAddr`.
  * Implemented `FromParam` for `PathBuf`
  * Implemented `FromParam`, `FromData`, and `FromForm` for `&str`.
  * Implemented `FromForm` for `Json<T>`, `MsgPack<T>`.
  * Implemented `FromFormField` for `Cow` and `Capped<Cow>>`
  * Implemented `Responder` for `tokio::fs::File`.
  * Implemented `Responder` for `(ContentType, R) where R: Responder`.
  * Implemented `Responder` for `(Status, R) where R: Responder` which overrides `R`'s status.
  * Implemented `Responder` for `std::io::Error` (behaves as `Debug<std::io::Error>`).
  * Implemented `Responder` for `Either<T, E>`, equivalently to `Result<T, E>`.
  * Implemented `Serialize` for `Flash`.
  * Implemented `Serialize`, `Deserialize`, `UriDisplay` and `FromUriParam` for `uuid::Uuid`
  * Implemented `Serialize`, `Deserialize` for `RawStr`.
  * Implemented `Serialize`, `Deserialize` for all URI types.

### Updated Dependencies

  * The `serde` dependency was introduced (`1.0`).
  * The `futures` dependency was introduced (`0.3`).
  * The `state` dependency was updated to `0.5`.
  * The `time` dependency was updated to `0.2`.
  * The `binascii` dependency was introduced (`0.1`).
  * The `ref-cast` dependency was introduced (`1.0`).
  * The `atomic` dependency was introduced (`0.5`).
  * The `parking_lot` dependency was introduced (`0.11`).
  * The `ubtye` dependency was introduced (`0.10`).
  * The `figment` dependency was introduced (`0.10`).
  * The `rand` dependency was introduced (`0.8`).
  * The `either` dependency was introduced (`1.0`).
  * The `pin-project-lite` dependency was introduced (`0.2`).
  * The `indexmap` dependency was introduced (`1.0`).
  * The `tempfile` dependency was introduced (`3.0`).
  * The `async-trait` dependency was introduced (`0.1`).
  * The `async-stream` dependency was introduced (`0.3`).
  * The `multer` dependency was introduced (`2.0`).
  * The `tokio` dependency was introduced (`1.6.1`).
  * The `tokio-util` dependency was introduced (`0.6`).
  * The `tokio-stream` dependency was introduced (`0.1.6`).
  * The `bytes` dependency was introduced (`1.0`).
  * The `rmp-serde` dependency was updated to `0.15`.
  * The `uuid` dependency was updated to `0.8`.
  * The `tera` dependency was updated to `1.10`.
  * The `handlebars` dependency was updated to `3.0`.
  * The `normpath` dependency was introduced (`0.3`).
  * The `postgres` dependency was updated to `0.19`.
  * The `rusqlite` dependency was updated to `0.25`.
  * The `r2d2_sqlite` dependency was updated to `0.18`.
  * The `memcache` dependency was updated to `0.15`.

## Infrastructure

  * Rocket now uses the 2018 edition of Rust.
  * Added visible `use` statements to examples in the guide.
  * Split examples into a separate workspace from the non-example crates.
  * Updated documentation for all changes.
  * Fixed many typos, errors, and broken links throughout documentation and examples.
  * Improved the general robustness of macros, and the quality and frequency of error messages.
  * Benchmarks now use `criterion` and datasets extracted from real-world projects.
  * Fixed the SPDX license expressions in `Cargo.toml` files.
  * Added support to `test.sh` for a `+` flag (e.g. `+stable`) to pass to `cargo`.
  * Added support to `test.sh` for extra flags to be passed on to `cargo`.
  * Migrated CI to Github Actions.

[`async`/`await`]: https://rocket.rs/v0.5-rc/guide/overview/#async-routes
[compilation on Rust's stable]: https://rocket.rs/v0.5-rc/guide/getting-started/#installing-rust
[Feature-complete forms support]: https://rocket.rs/v0.5-rc/guide/requests/#forms
[configuration system]: https://rocket.rs/v0.5-rc/guide/configuration/#configuration
[graceful shutdown]: https://api.rocket.rs/v0.5-rc/rocket/config/struct.Shutdown.html#summary
[asynchronous testing]: https://rocket.rs/v0.5-rc/guide/testing/#asynchronous-testing
[UTF-8 characters]: https://rocket.rs/v0.5-rc/guide/requests/#static-parameters
[ignorable segments]: https://rocket.rs/v0.5-rc/guide/requests/#ignored-segments
[Catcher scoping]: https://rocket.rs/v0.5-rc/guide/requests/#scoping
[ad-hoc validation]: https://rocket.rs/v0.5-rc/guide/requests#ad-hoc-validation
[incoming data limits]: https://rocket.rs/v0.5-rc/guide/requests/#streaming
[build phases]: https://api.rocket.rs/v0.5-rc/rocket/struct.Rocket.html#phases
[Singleton fairings]: https://api.rocket.rs/v0.5-rc/rocket/fairing/trait.Fairing.html#singletons
[features into core]: https://api.rocket.rs/v0.5-rc/rocket/index.html#features
[features of `rocket`]: https://api.rocket.rs/v0.5-rc/rocket/index.html#features
[Data limit declaration in SI units]: https://api.rocket.rs/v0.5-rc/rocket/data/struct.ByteUnit.html
[support for `serde`]: https://api.rocket.rs/v0.5-rc/rocket/serde/index.html
[automatic typed config extraction]: https://api.rocket.rs/v0.5-rc/rocket/fairing/struct.AdHoc.html#method.config
[misconfigured secrets]: https://api.rocket.rs/v0.5-rc/rocket/config/struct.SecretKey.html
[default ranking colors]: https://rocket.rs/v0.5-rc/guide/requests/#default-ranking
[`chat`]: https://github.com/SergioBenitez/Rocket/tree/v0.5-rc/examples/chat
[`Form` guard]: https://api.rocket.rs/v0.5-rc/rocket/form/struct.Form.html
[`Strict`]: https://api.rocket.rs/v0.5-rc/rocket/form/struct.Strict.html
[`CookieJar`#pending]: https://api.rocket.rs/v0.5-rc/rocket/http/struct.CookieJar.html#pending
[`rocket::serde::json`]: https://api.rocket.rs/v0.5-rc/rocket/serde/json/index.html
[`rocket::serde::msgpack`]: https://api.rocket.rs/v0.5-rc/rocket/serde/msgpack/index.html
[`rocket::serde::uuid`]: https://api.rocket.rs/v0.5-rc/rocket/serde/uuid/index.html
[`rocket::shield`]: https://api.rocket.rs/v0.5-rc/rocket/shield/index.html
[`rocket::fs`]: https://api.rocket.rs/v0.5-rc/rocket/fs/index.html
[`async run()`]: https://api.rocket.rs/v0.5-rc/rocket_sync_db_pools/index.html#handlers
[`LocalRequest::json()`]: https://api.rocket.rs/v0.5-rc/rocket/local/blocking/struct.LocalRequest.html#method.json
[`LocalRequest::msgpack()`]: https://api.rocket.rs/v0.5-rc/rocket/local/blocking/struct.LocalRequest.html#method.msgpack
[`LocalResponse::json()`]: https://api.rocket.rs/v0.5-rc/rocket/local/blocking/struct.LocalResponse.html#method.json
[`LocalResponse::msgpack()`]: https://api.rocket.rs/v0.5-rc/rocket/local/blocking/struct.LocalResponse.html#method.msgpack
[hierarchical data limits]: https://api.rocket.rs/v0.5-rc/rocket/data/struct.Limits.html#hierarchy
[default form field values]: https://rocket.rs/v0.5-rc/guide/requests/#defaults
[`Config::ident`]: https://api.rocket.rs/rocket/struct.Config.html#structfield.ident
[`tokio`]: https://tokio.rs/
[Figment]: https://docs.rs/figment/0.10/figment/
[`TempFile`]: https://api.rocket.rs/v0.5-rc/rocket/fs/enum.TempFile.html
[`Contextual`]: https://rocket.rs/v0.5-rc/guide/requests/#context
[`Capped<T>`]: https://api.rocket.rs/v0.5-rc/rocket/data/struct.Capped.html
[default catchers]: https://rocket.rs/v0.5-rc/guide/requests/#default-catchers
[URI types]: https://api.rocket.rs/v0.5-rc/rocket/http/uri/index.html
[`uri!`]: https://api.rocket.rs/v0.5-rc/rocket/macro.uri.html
[`Reference`]: https://api.rocket.rs/v0.5-rc/rocket/http/uri/struct.Reference.html
[`Asterisk`]: https://api.rocket.rs/v0.5-rc/rocket/http/uri/struct.Asterisk.html
[`Redirect`]: https://api.rocket.rs/v0.5-rc/rocket/response/struct.Redirect.html
[`UriDisplayQuery`]: https://api.rocket.rs/v0.5-rc/rocket/derive.UriDisplayQuery.html
[`Shield`]: https://api.rocket.rs/v0.5-rc/rocket/shield/struct.Shield.html
[Sentinels]: https://api.rocket.rs/v0.5-rc/rocket/trait.Sentinel.html
[`local_cache!`]: https://api.rocket.rs/v0.5-rc/rocket/request/macro.local_cache.html
[`local_cache_once!`]: https://api.rocket.rs/v0.5-rc/rocket/request/macro.local_cache_once.html
[`CookieJar`]: https://api.rocket.rs/v0.5-rc/rocket/http/struct.CookieJar.html
[asynchronous streams]: https://rocket.rs/v0.5-rc/guide/responses/#async-streams
[Server-Sent Events]: https://api.rocket.rs/v0.5-rc/rocket/response/stream/struct.EventStream.html
[`fs::relative!`]: https://api.rocket.rs/v0.5-rc/rocket/fs/macro.relative.html
[`Shutdown`]: https://api.rocket.rs/v0.5-rc/rocket/struct.Shutdown.html
[`Rocket`]: https://api.rocket.rs/v0.5-rc/rocket/struct.Rocket.html
[`rocket::build()`]: https://api.rocket.rs/v0.5-rc/rocket/struct.Rocket.html#method.build
[`Rocket::ignite()`]: https://api.rocket.rs/v0.5-rc/rocket/struct.Rocket.html#method.ignite
[`Rocket::launch()`]: https://api.rocket.rs/v0.5-rc/rocket/struct.Rocket.html#method.launch
[`Request::rocket()`]: https://api.rocket.rs/v0.5-rc/rocket/request/struct.Request.html#method.rocket
[Fairings]: https://rocket.rs/v0.5-rc/guide/fairings/
[configuration system]: https://rocket.rs/v0.5-rc/guide/configuration/
[`Poolable`]: https://api.rocket.rs/v0.5-rc/rocket_sync_db_pools/trait.Poolable.html
[`Config`]: https://api.rocket.rs/v0.5-rc/rocket/struct.Config.html
[`Error`]: https://api.rocket.rs/v0.5-rc/rocket/struct.Error.html
[`LogLevel`]: https://api.rocket.rs/v0.5-rc/rocket/config/enum.LogLevel.html
[`Rocket::register()`]: https://api.rocket.rs/v0.5-rc/rocket/struct.Rocket.html#method.register
[`NamedFile::open`]: https://api.rocket.rs/v0.5-rc/rocket/fs/struct.NamedFile.html#method.open
[`Request::local_cache_async()`]: https://api.rocket.rs/v0.5-rc/rocket/request/struct.Request.html#method.local_cache_async
[`FromRequest`]: https://api.rocket.rs/v0.5-rc/rocket/request/trait.FromRequest.html
[`Fairing`]: https://api.rocket.rs/v0.5-rc/rocket/fairing/trait.Fairing.html
[`catcher::Handler`]: https://api.rocket.rs/v0.5-rc/rocket/catcher/trait.Handler.html
[`route::Handler`]: https://api.rocket.rs/v0.5-rc/rocket/route/trait.Handler.html
[`FromData`]: https://api.rocket.rs/v0.5-rc/rocket/data/trait.FromData.html
[`AsyncRead`]: https://docs.rs/tokio/1/tokio/io/trait.AsyncRead.html
[`AsyncSeek`]: https://docs.rs/tokio/1/tokio/io/trait.AsyncSeek.html
[`rocket::local::asynchronous`]: https://api.rocket.rs/v0.5-rc/rocket/local/asynchronous/index.html
[`rocket::local::blocking`]: https://api.rocket.rs/v0.5-rc/rocket/local/blocking/index.html
[`Outcome`]: https://api.rocket.rs/v0.5-rc/rocket/outcome/enum.Outcome.html
[`rocket::outcome::try_outcome!`]: https://api.rocket.rs/v0.5-rc/rocket/outcome/macro.try_outcome.html
[`Result<T, E>` implements `Responder`]: https://api.rocket.rs/v0.5-rc/rocket/response/trait.Responder.html#provided-implementations
[`Debug`]: https://api.rocket.rs/v0.5-rc/rocket/response/struct.Debug.html
[`std::convert::Infallible`]: https://doc.rust-lang.org/stable/std/convert/enum.Infallible.html
[`ErrorKind::Collisions`]: https://api.rocket.rs/v0.5-rc/rocket/error/enum.ErrorKind.html#variant.Collisions
[`rocket::http::uri::fmt`]: https://api.rocket.rs/v0.5-rc/rocket/http/uri/fmt/index.html
[`Data::open()`]: https://api.rocket.rs/v0.5-rc/rocket/data/struct.Data.html#method.open
[`DataStream`]: https://api.rocket.rs/v0.5-rc/rocket/data/struct.DataStream.html
[`rocket::form`]: https://api.rocket.rs/v0.5-rc/rocket/form/index.html
[`FromFormField`]: https://api.rocket.rs/v0.5-rc/rocket/form/trait.FromFormField.html
[`FromForm`]: https://api.rocket.rs/v0.5-rc/rocket/form/trait.FromForm.html
[`FlashMessage`]: https://api.rocket.rs/v0.5-rc/rocket/request/type.FlashMessage.html
[`Flash`]: https://api.rocket.rs/v0.5-rc/rocket/response/struct.Flash.html
[`rocket::State`]: https://api.rocket.rs/v0.5-rc/rocket/struct.State.html
[`Segments<Path>` and `Segments<Query>`]: https://api.rocket.rs/v0.5-rc/rocket/http/uri/struct.Segments.html
[`Route::map_base()`]: https://api.rocket.rs/v0.5-rc/rocket/route/struct.Route.html#method.map_base
[`uuid` support]: https://api.rocket.rs/v0.5-rc/rocket/serde/uuid/index.html
[`json`]: https://api.rocket.rs/v0.5-rc/rocket/serde/json/index.html
[`msgpack`]: https://api.rocket.rs/v0.5-rc/rocket/serde/msgpack/index.html
[`rocket::serde::json::json!`]: https://api.rocket.rs/v0.5-rc/rocket/serde/json/macro.json.html
[`rocket::shield::Shield`]: https://api.rocket.rs/v0.5-rc/rocket/shield/struct.Shield.html
[`rocket::fs::FileServer`]: https://api.rocket.rs/v0.5-rc/rocket/fs/struct.FileServer.html
[`rocket_dyn_templates`]: https://api.rocket.rs/v0.5-rc/rocket_dyn_templates/index.html
[`rocket_sync_db_pools`]: https://api.rocket.rs/v0.5-rc/rocket_sync_db_pools/index.html
[multitasking]: https://rocket.rs/v0.5-rc/guide/overview/#multitasking
[`Created<R>`]: https://api.rocket.rs/v0.5-rc/rocket/response/status/struct.Created.html
[`Created::tagged_body`]: https://api.rocket.rs/v0.5-rc/rocket/response/status/struct.Created.html#method.tagged_body
[raw identifiers]: https://doc.rust-lang.org/1.51.0/book/appendix-01-keywords.html#raw-identifiers
[`Rocket::config()`]: https://api.rocket.rs/v0.5-rc/rocket/struct.Rocket.html#method.config
[`Rocket::figment()`]: https://api.rocket.rs/v0.5-rc/rocket/struct.Rocket.html#method.figment
[`Rocket::state()`]: https://api.rocket.rs/v0.5-rc/rocket/struct.Rocket.html#method.state
[`Rocket::catchers()`]: https://api.rocket.rs/v0.5-rc/rocket/struct.Rocket.html#method.catchers
[`LocalRequest::inner_mut()`]: https://api.rocket.rs/v0.5-rc/rocket/local/blocking/struct.LocalRequest.html#method.inner_mut
[`RawStrBuf`]: https://api.rocket.rs/v0.5-rc/rocket/http/struct.RawStrBuf.html
[`RawStr`]: https://api.rocket.rs/v0.5-rc/rocket/http/struct.RawStr.html
[`RawStr::percent_encode()`]: https://api.rocket.rs/v0.5-rc/rocket/http/struct.RawStr.html#method.percent_encode
[`RawStr::percent_encode_bytes()`]: https://api.rocket.rs/v0.5-rc/rocket/http/struct.RawStr.html#method.percent_encode_bytes
[`RawStr::strip()`]: https://api.rocket.rs/v0.5-rc/rocket/http/struct.RawStr.html#method.strip_prefix
[`rocket::catcher`]: https://api.rocket.rs/v0.5-rc/rocket/catcher/index.html
[`rocket::route`]: https://api.rocket.rs/v0.5-rc/rocket/route/index.html
[`Segments::prefix_of()`]: https://api.rocket.rs/v0.5-rc/rocket/http/uri/struct.Segments.html#method.prefix_of
[`Template::try_custom()`]: https://api.rocket.rs/v0.5-rc/rocket_dyn_templates/struct.Template.html#method.try_custom
[`Template::custom`]: https://api.rocket.rs/v0.5-rc/rocket_dyn_templates/struct.Template.html#method.custom
[`FileServer::new()`]: https://api.rocket.rs/v0.5-rc/rocket/fs/struct.FileServer.html#method.new
[`content`]: https://api.rocket.rs/v0.5-rc/rocket/response/content/index.html
[`rocket_db_pools`]: https://api.rocket.rs/v0.5-rc/rocket_db_pools/index.html
[mutual TLS]: https://rocket.rs/v0.5-rc/guide/configuration/#mutual-tls
[`Certificate`]: https://api.rocket.rs/v0.5-rc/rocket/mtls/struct.Certificate.html
[`MediaType::with_params()`]: https://api.rocket.rs/v0.5-rc/rocket/http/struct.MediaType.html#method.with_params
[`ContentType::with_params()`]: https://api.rocket.rs/v0.5-rc/rocket/http/struct.ContentType.html#method.with_params
[`Host`]: https://api.rocket.rs/v0.5-rc/rocket/http/uri/struct.Host.html
[`&Host`]: https://api.rocket.rs/v0.5-rc/rocket/http/uri/struct.Host.html
[`Request::host()`]: https://api.rocket.rs/v0.5-rc/rocket/request/struct.Request.html#method.host
[`context!`]: https://api.rocket.rs/v0.5-rc/rocket_dyn_templates/macro.context.html
[`MediaType`]: https://api.rocket.rs/v0.5-rc/rocket/http/struct.MediaType.html
[`ContentType`]: https://api.rocket.rs/v0.5-rc/rocket/http/struct.ContentType.html
[`Method`]: https://api.rocket.rs/v0.5-rc/rocket/http/enum.Method.html

# Version 0.4.10 (May 21, 2021)

## Core

  * [[`3276b8`]] Removed used of `unsafe` in `Origin::parse_owned()`, fixing a
    soundness issue.

[`3276b8`]: https://github.com/SergioBenitez/Rocket/commit/3276b8

# Version 0.4.9 (May 19, 2021)

## Core

  * [[`#1645`], [`f2a56f`]] Fixed `Try` `impl FromResidual<Result> for Outcome`.

[`#1645`]: https://github.com/SergioBenitez/Rocket/issues/1645
[`f2a56f`]: https://github.com/SergioBenitez/Rocket/commit/f2a56f

# Version 0.4.8 (May 18, 2021)

## Core

  * [[`#1548`], [`93e88b0`]] Fixed an issue that prevented compilation under
    Windows Subsystem for Linux v1.
  * Updated `Outcome` `Try` implementation to v2 in latest nightly.
  * Minimum required `rustc` is `1.54.0-nightly (2021-05-18)`.

## Internal

  * Updated `base64` dependency to `0.13`.

[`#1548`]: https://github.com/SergioBenitez/Rocket/issues/1548
[`93e88b0`]: https://github.com/SergioBenitez/Rocket/commit/93e88b0

# Version 0.4.7 (Feb 09, 2021)

## Core

  * [[#1534], [`2059a6`]] Fixed a low-severity, minimal impact soundness issue
    in `uri::Formatter`.

[#1534]: https://github.com/SergioBenitez/Rocket/issues/1534
[`2059a6`]: https://github.com/SergioBenitez/Rocket/commit/2059a6

# Version 0.4.6 (Nov 09, 2020)

## Core

  * [[`86bd7c`]] Added default and configurable read/write timeouts:
    `read_timeout` and `write_timeout`.
  * [[`c24a96`]] Added the `sse` feature, which [enables flushing] by returning
    `io::ErrorKind::WouldBlock`.

## Docs

  * Fixed broken doc links in `contrib`.
  * Fixed database library versions in `contrib` docs.

## Internal

  * Updated source code for Rust 2018.
  * UI tests now use `trybuild` instead of `compiletest-rs`.

[`86bd7c`]: https://github.com/SergioBenitez/Rocket/commit/86bd7c
[`c24a96`]: https://github.com/SergioBenitez/Rocket/commit/c24a96
[enables flushing]: https://api.rocket.rs/v0.4/rocket/response/struct.Stream.html#buffering-and-blocking

# Version 0.4.5 (May 30, 2020)

## Core

  * [[#1312], [`89150f`]] Fixed a low-severity, minimal impact soundness issue in
    `LocalRequest::clone()`.
  * [[#1263], [`376f74`]] Fixed a cookie serialization issue that led to
    incorrect cookie deserialization in certain cases.
  * Removed dependency on `ring` for private cookies and thus Rocket, by
    default.
  * Added [`Origin::map_path()`] for manipulating `Origin` paths.
  * Added [`handler::Outcome::from_or_forward()`].
  * Added [`Options::NormalizeDirs`] option to `StaticFiles`.
  * Improved accessibility of default error HTML.

## Docs

  * Fixed various typos.

[#1312]: https://github.com/SergioBenitez/Rocket/issues/1312
[`89150f`]: https://github.com/SergioBenitez/Rocket/commit/89150f
[#1263]: https://github.com/SergioBenitez/Rocket/issues/1263
[`376f74`]: https://github.com/SergioBenitez/Rocket/commit/376f74
[`Origin::map_path()`]: https://api.rocket.rs/v0.4/rocket/http/uri/struct.Origin.html#method.map_path
[`handler::Outcome::from_or_forward()`]: https://api.rocket.rs/v0.4/rocket/handler/type.Outcome.html#method.from_or_forward
[`Options::NormalizeDirs`]: https://api.rocket.rs/v0.4/rocket_contrib/serve/struct.Options.html#associatedconstant.NormalizeDirs

# Version 0.4.4 (Mar 09, 2020)

## Core

  * Removed use of unsupported `cfg(debug_assertions)` in `Cargo.toml`, allowing
    for builds on latest nightlies.

## Docs

  * Fixed various broken links.

# Version 0.4.3 (Feb 29, 2020)

## Core

  * Added a new [`Debug`] `500` `Responder` that `Debug`-prints its contents on
    response.
  * Specialization on `Result` was deprecated. [`Debug`] can be used in place of
    non-`Responder` errors.
  * Fixed an issue that resulted in cookies not being set on error responses.
  * Various `Debug` implementations on Rocket types now respect formatting
    options.
  * Added `Responder`s for various HTTP status codes: [`NoContent`],
    [`Unauthorized`], [`Forbidden`], and [`Conflict`].
  * `FromParam` is implemented for `NonZero` core types.

## Codegen

  * Docs for Rocket-generated macros are now hidden.
  * Generated code now works even when prelude imports like `Some`, `Ok`, and
    `Err` are shadowed.
  * Error messages referring to responder types in routes now point to the type
    correctly.

## Docs

  * All code examples in the guide are now tested and guaranteed to compile.
  * All macros are documented in the `core` crate; `rocket_codegen` makes no
    appearances.

## Infrastructure

  * CI was moved from Travis to Azure Pipelines; Windows support is tested.
  * Rocket's chat moved to [Matrix] and [Freenode].

[`Debug`]: https://api.rocket.rs/v0.4/rocket/response/struct.Debug.html
[`NoContent`]: https://api.rocket.rs/v0.4/rocket/response/status/struct.NoContent.html
[`Unauthorized`]: https://api.rocket.rs/v0.4/rocket/response/status/struct.Unauthorized.html
[`Forbidden`]: https://api.rocket.rs/v0.4/rocket/response/status/struct.Forbidden.html
[`Conflict`]: https://api.rocket.rs/v0.4/rocket/response/status/struct.Conflict.html
[Matrix]: https://chat.mozilla.org/#/room/#rocket:mozilla.org
[Freenode]: https://kiwiirc.com/client/chat.freenode.net/#rocket

# Version 0.4.2 (Jun 28, 2019)

## Core

  * Replaced use of `FnBox` with `Box<dyn FnOnce>`.
  * Removed the stable feature gates `try_from` and `transpose_result`.
  * Derive macros are reexported alongside their respective traits.
  * Minimum required `rustc` is `1.35.0-nightly (2019-04-05)`.

## Codegen

  * `JsonValue` now implements `FromIterator`.
  * `non_snake_case` errors are silenced in generated code.
  * Minimum required `rustc` is `1.33.0-nightly (2019-01-03)`.

## Contrib

  * Allow setting custom ranks on `StaticFiles` via [`StaticFiles::rank()`].
  * `MsgPack` correctly sets a MessagePack Content-Type on responses.

## Docs

  * Fixed typos across rustdocs and guide.
  * Documented library versions in contrib database documentation.

## Infrastructure

  * Updated internal dependencies to their latest versions.

[`StaticFiles::rank()`]: https://api.rocket.rs/v0.4/rocket_contrib/serve/struct.StaticFiles.html#method.rank

# Version 0.4.1 (May 11, 2019)

## Core

  * Rocket's default `Server` HTTP header no longer overrides a user-set header.
  * Fixed encoding and decoding of certain URI characters.

## Codegen

  * Compiler diagnostic information is more reliably produced.

## Contrib

  * Database pool types now implement `DerefMut`.
  * Added support for memcache connection pools.
  * Stopped depending on default features from core.

## Docs

  * Fixed many typos across the rustdocs and guide.
  * Added guide documentation on mounting more than one route at once.

## Infrastructure

  * Testing no longer requires "bootstrapping".
  * Removed deprecated `isatty` dependency in favor of `atty`.

# Version 0.4.0 (Dec 06, 2018)

## New Features

This release includes the following new features:

  * Introduced [Typed URIs].
  * Introduced [ORM agnostic database support].
  * Introduced [Request-Local State].
  * Introduced mountable static-file serving via [`StaticFiles`].
  * Introduced automatic [live template reloading].
  * Introduced custom stateful handlers via [`Handler`].
  * Introduced [transforming] data guards via [`FromData::transform()`].
  * Introduced revamped [query string handling].
  * Introduced the [`SpaceHelmet`] security and privacy headers fairing.
  * Private cookies are gated behind a `private-cookies` default feature.
  * Added [derive for `FromFormValue`].
  * Added [derive for `Responder`].
  * Added [`Template::custom()`] for customizing templating engines including
    registering filters and helpers.
  * Cookies are automatically tracked and propagated by [`Client`].
  * Private cookies can be added to local requests with
    [`LocalRequest::private_cookie()`].
  * Release builds default to the `production` environment.
  * Keep-alive can be configured via the `keep_alive` configuration parameter.
  * Allow CLI colors and emoji to be disabled with `ROCKET_CLI_COLORS=off`.
  * Route `format` accepts [shorthands] such as `json` and `html`.
  * Implemented [`Responder` for `Status`].
  * Added [`Response::cookies()`] for retrieving response cookies.
  * All logging is disabled when `log` is set to `off`.
  * Added [`Metadata`] guard for retrieving templating information.
  * The [`Uri`] type parses URIs according to RFC 7230 into one of [`Origin`],
    [`Absolute`], or [`Authority`].
  * Added [`Outcome::and_then()`], [`Outcome::failure_then()`], and
    [`Outcome::forward_then()`].
  * Implemented `Responder` for `&[u8]`.
  * Any `T: Into<Vec<Route>>` can be [`mount()`]ed.
  * [Default rankings] range from -6 to -1, differentiating on static query
    strings.
  * Added [`Request::get_query_value()`] for retrieving a query value by key.
  * Applications can launch without a working directory.
  * Added [`State::from()`] for constructing `State` values.

[`SpaceHelmet`]: https://api.rocket.rs/v0.4/rocket_contrib/helmet/index.html
[`State::from()`]: https://api.rocket.rs/v0.4/rocket/struct.State.html#method.from
[Typed URIs]: https://rocket.rs/v0.4/guide/responses/#typed-uris
[ORM agnostic database support]: https://rocket.rs/v0.4/guide/state/#databases
[`Template::custom()`]: https://api.rocket.rs/v0.4/rocket_contrib/templates/struct.Template.html#method.custom
[`LocalRequest::private_cookie()`]: https://api.rocket.rs/v0.4/rocket/local/struct.LocalRequest.html#method.private_cookie
[`LocalRequest`]: https://api.rocket.rs/v0.4/rocket/local/struct.LocalRequest.html
[shorthands]: https://api.rocket.rs/v0.4/rocket/http/struct.ContentType.html#method.parse_flexible
[derive for `FromFormValue`]: https://api.rocket.rs/v0.4/rocket_codegen/derive.FromFormValue.html
[derive for `Responder`]: https://api.rocket.rs/v0.4/rocket_codegen/derive.Responder.html
[`Response::cookies()`]: https://api.rocket.rs/v0.4/rocket/struct.Response.html#method.cookies
[`Client`]: https://api.rocket.rs/v0.4/rocket/local/struct.Client.html
[Request-Local State]: https://rocket.rs/v0.4/guide/state/#request-local-state
[`Metadata`]: https://api.rocket.rs/v0.4/rocket_contrib/templates/struct.Metadata.html
[`Uri`]: https://api.rocket.rs/v0.4/rocket/http/uri/enum.Uri.html
[`Origin`]: https://api.rocket.rs/v0.4/rocket/http/uri/struct.Origin.html
[`Absolute`]: https://api.rocket.rs/v0.4/rocket/http/uri/struct.Absolute.html
[`Authority`]: https://api.rocket.rs/v0.4/rocket/http/uri/struct.Authority.html
[`Outcome::and_then()`]: https://api.rocket.rs/v0.4/rocket/enum.Outcome.html#method.and_then
[`Outcome::forward_then()`]: https://api.rocket.rs/v0.4/rocket/enum.Outcome.html#method.forward_then
[`Outcome::failure_then()`]: https://api.rocket.rs/v0.4/rocket/enum.Outcome.html#method.failure_then
[`StaticFiles`]: https://api.rocket.rs/v0.4/rocket_contrib/serve/struct.StaticFiles.html
[live template reloading]: https://rocket.rs/v0.4/guide/responses/#live-reloading
[`Handler`]: https://api.rocket.rs/v0.4/rocket/trait.Handler.html
[`mount()`]: https://api.rocket.rs/v0.4/rocket/struct.Rocket.html#method.mount
[`FromData::transform()`]: https://api.rocket.rs/v0.4/rocket/data/trait.FromData.html#tymethod.transform
[transforming]: https://api.rocket.rs/v0.4/rocket/data/trait.FromData.html#transforming
[query string handling]: https://rocket.rs/v0.4/guide/requests/#query-strings
[Default rankings]: https://rocket.rs/v0.4/guide/requests/#default-ranking
[`Request::get_query_value()`]: https://api.rocket.rs/v0.4/rocket/struct.Request.html#method.get_query_value
[`Responder` for `Status`]: https://rocket.rs/v0.4/guide/responses/#status

## Codegen Rewrite

The [`rocket_codegen`] crate has been entirely rewritten using to-be-stable
procedural macro APIs. We expect nightly breakages to drop dramatically, likely
to zero, as a result. The new prelude import for Rocket applications is:

```diff
- #![feature(plugin)]
- #![plugin(rocket_codegen)]
+ #![feature(proc_macro_hygiene, decl_macro)]

- extern crate rocket;
+ #[macro_use] extern crate rocket;
```

The [`rocket_codegen`] crate should **_not_** be a direct dependency. Remove it
from your `Cargo.toml`:

```diff
[dependencies]
- rocket = "0.3"
+ rocket = "0.4"
- rocket_codegen = "0.3"
```

[`rocket_codegen`]: https://api.rocket.rs/v0.4/rocket_codegen/index.html

## Breaking Changes

This release includes many breaking changes. These changes are listed below
along with a short note about how to handle the breaking change in existing
applications when applicable.

  * **Route and catcher attributes respect function privacy.**

    To mount a route or register a catcher outside of the module it is declared,
    ensure that the handler function is marked `pub` or `crate`.

  * **Query handling syntax has been completely revamped.**

    A query parameter of `<param>` is now `<param..>`. Consider whether your
    application benefits from the revamped [query string handling].

  * **The `#[error]` attribute and `errors!` macro were removed.**

    Use `#[catch]` and `catchers!` instead.

  * **`Rocket::catch()` was renamed to [`Rocket::register()`].**

    Change calls of the form `.catch(errors![..])` to
    `.register(catchers![..])`.

  * **The `#[catch]` attribute only accepts functions with 0 or 1 argument.**

    Ensure the argument to the catcher, if any, is of type `&Request`.

  * **[`json!`] returns a [`JsonValue`], no longer needs wrapping.**

    Change instances of `Json(json!(..))` to `json!` and change the
    corresponding type to `JsonValue`.

  * **All environments default to port 8000.**

    Manually configure a port of `80` for the `stage` and `production`
    environments for the previous behavior.

  * **Release builds default to the production environment.**

    Manually set the environment to `debug` with `ROCKET_ENV=debug` for the
    previous behavior.

  * **[`Form`] and [`LenientForm`] lost a lifetime parameter, `get()` method.**

    Change a type of `Form<'a, T<'a>>` to `Form<T>` or `Form<T<'a>>`. `Form<T>`
    and `LenientForm<T>` now implement `Deref<Target = T>`, allowing for calls
    to `.get()` to be removed.

  * **[`ring`] was updated to 0.13.**

    Ensure all transitive dependencies to `ring` refer to version `0.13`.

  * **`Uri` was largely replaced by [`Origin`].**

    In general, replace the type `Uri` with `Origin`. The `base` and `uri`
    fields of [`Route`] are now of type [`Origin`]. The `&Uri` guard is now
    `&Origin`. [`Request::uri()`] now returns an [`Origin`].

  * **All items in [`rocket_contrib`] are namespaced behind modules.**

    * `Json` is now `json::Json`
    * `MsgPack` is now `msgpack::MsgPack`
    * `MsgPackError` is now `msgpack::Error`
    * `Template` is now `templates::Template`
    * `UUID` is now `uuid::Uuid`
    * `Value` is replaced by `json::JsonValue`

  * **TLS certificates require the `subjectAltName` extension.**

    Ensure that your TLS certificates contain the `subjectAltName` extension
    with a value set to your domain.

  * **Route paths, mount points, and [`LocalRequest`] URIs are strictly
    checked.**

    Ensure your mount points are absolute paths with no parameters, ensure your
    route paths are absolute paths with proper parameter syntax, and ensure that
    paths passed to `LocalRequest` are valid.

  * **[`Template::show()`] takes an `&Rocket`, doesn't accept a `root`.**

    Use [`client.rocket()`] to get a reference to an instance of `Rocket` when
    testing. Use [`Template::render()`] in routes.

  * **[`Request::remote()`] returns the _actual_ remote IP, doesn't rewrite.**

    Use [`Request::real_ip()`] or [`Request::client_ip()`] to retrieve the IP
    address from the "X-Real-IP" header if it is present.

  * **[`Bind`] variant was added to [`LaunchErrorKind`].**

    Ensure matches on `LaunchErrorKind` include or ignore the `Bind` variant.

  * **Cookies are automatically tracked and propagated by [`Client`].**

    For the previous behavior, construct a `Client` with
    [`Client::untracked()`].

  * **`UUID` was renamed to [`Uuid`].**

    Use `Uuid` instead of `UUID`.

  * **`LocalRequest::cloned_dispatch()` was removed.**

    Chain calls to `.clone().dispatch()` for the previous behavior.

  * **[`Redirect`] constructors take a generic type of `T:
    TryInto<Uri<'static>>`.**

    A call to a `Redirect` constructor with a non-`'static` `&str`  of the form
    `Redirect::to(string)` should become `Redirect::to(string.to_string())`,
    heap-allocating the string before being passed to the constructor.

  * **The [`FromData`] impl for [`Form`] and [`LenientForm`] now return an error
    of type [`FormDataError`].**

    On non-I/O errors, the form string is stored in the variant as an `&'f str`.

  * **[`Missing`] variant was added to [`ConfigError`].**

    Ensure matches on `ConfigError` include or ignore the `Missing` variant.

  * **The [`FromData`] impl for [`Json`] now returns an error of type
    [`JsonError`].**

    The previous `SerdeError` is now the `.1` member of the `JsonError` `enum`.
    Match and destruct the variant for the previous behavior.

  * **[`FromData`] is now emulated by [`FromDataSimple`].**

    Change _implementations_, not uses, of `FromData` to `FromDataSimple`.
    Consider whether your implementation could benefit from [transformations].

  * **[`FormItems`] iterates over values of type [`FormItem`].**

    Map using `.map(|item| item.key_value())` for the previous behavior.

  * **[`LaunchErrorKind::Collision`] contains a vector of the colliding routes.**

    Destruct using `LaunchErrorKind::Collision(..)` to ignore the vector.

  * **[`Request::get_param()`] and [`Request::get_segments()`] are indexed by
    _segment_, not dynamic parameter.**

    Modify the `n` argument in calls to these functions appropriately.

  * **Method-based route attributes no longer accept a keyed `path` parameter.**

    Change an attribute of the form `#[get(path = "..")]` to `#[get("..")]`.

  * **[`Json`] and [`MsgPack`] data guards no longer reject requests with an
    unexpected Content-Type**

    To approximate the previous behavior, add a `format = "json"` route
    parameter when using `Json` or `format = "msgpack"` when using `MsgPack`.

  * **Implemented [`Responder` for `Status`]. Removed `Failure`,
    `status::NoContent`, and `status::Reset` responders.**

    Replace uses of `Failure(status)` with `status` directly. Replace
    `status::NoContent` with `Status::NoContent`. Replace `status::Reset` with
    `Status::ResetContent`.

  * **[`Config::root()`] returns an `Option<&Path>` instead of an `&Path`.**

    For the previous behavior, use `config.root().unwrap()`.

  * **[`Status::new()`] is no longer `const`.**

    Construct a `Status` directly.

  * **[`Config`] constructors return a `Config` instead of a `Result<Config>`.**

  * **`ConfigError::BadCWD`, `Config.config_path` were removed.**

  * **[`Json`] no longer has a default value for its type parameter.**

  * **Using `data` on a non-payload method route is a warning instead of error.**

  * **The `raw_form_string` method of [`Form`] and [`LenientForm`] was
    removed.**

  * **Various impossible `Error` associated types are now set to `!`.**

  * **All [`AdHoc`] constructors require a name as the first parameter.**

  * **The top-level `Error` type was removed.**

[`LaunchErrorKind::Collision`]: https://api.rocket.rs/v0.4/rocket/error/enum.LaunchErrorKind.html#variant.Collision
[`json!`]: https://api.rocket.rs/v0.4/rocket_contrib/macro.json.html
[`JsonValue`]: https://api.rocket.rs/v0.4/rocket_contrib/json/struct.JsonValue.html
[`Json`]: https://api.rocket.rs/v0.4/rocket_contrib/json/struct.Json.html
[`ring`]: https://crates.io/crates/ring
[`Template::show()`]: https://api.rocket.rs/v0.4/rocket_contrib/templates/struct.Template.html#method.show
[`Template::render()`]: https://api.rocket.rs/v0.4/rocket_contrib/templates/struct.Template.html#method.render
[`client.rocket()`]: https://api.rocket.rs/v0.4/rocket/local/struct.Client.html#method.rocket
[`Request::remote()`]: https://api.rocket.rs/v0.4/rocket/struct.Request.html#method.remote
[`Request::real_ip()`]: https://api.rocket.rs/v0.4/rocket/struct.Request.html#method.real_ip
[`Request::client_ip()`]: https://api.rocket.rs/v0.4/rocket/struct.Request.html#method.client_ip
[`Bind`]: https://api.rocket.rs/v0.4/rocket/error/enum.LaunchErrorKind.html#variant.Bind
[`LaunchErrorKind`]: https://api.rocket.rs/v0.4/rocket/error/enum.LaunchErrorKind.html
[`Client::untracked()`]: https://api.rocket.rs/v0.4/rocket/local/struct.Client.html#method.untracked
[`Uuid`]: https://api.rocket.rs/v0.4/rocket_contrib/uuid/struct.Uuid.html
[`Route`]: https://api.rocket.rs/v0.4/rocket/struct.Route.html
[`Redirect`]: https://api.rocket.rs/v0.4/rocket/response/struct.Redirect.html
[`Request::uri()`]: https://api.rocket.rs/v0.4/rocket/struct.Request.html#method.uri
[`FormDataError`]: https://api.rocket.rs/v0.4/rocket/request/enum.FormDataError.html
[`FromData`]: https://api.rocket.rs/v0.4/rocket/data/trait.FromData.html
[`Form`]: https://api.rocket.rs/v0.4/rocket/request/struct.Form.html
[`LenientForm`]: https://api.rocket.rs/v0.4/rocket/request/struct.LenientForm.html
[`AdHoc`]: https://api.rocket.rs/v0.4/rocket/fairing/struct.AdHoc.html
[`Missing`]: https://api.rocket.rs/v0.4/rocket/config/enum.ConfigError.html#variant.Missing
[`ConfigError`]: https://api.rocket.rs/v0.4/rocket/config/enum.ConfigError.html
[`Rocket::register()`]: https://api.rocket.rs/v0.4/rocket/struct.Rocket.html#method.register
[`JsonError`]: https://api.rocket.rs/v0.4/rocket_contrib/json/enum.JsonError.html
[transformations]: https://api.rocket.rs/v0.4/rocket/data/trait.FromData.html#transforming
[`FromDataSimple`]: https://api.rocket.rs/v0.4/rocket/data/trait.FromDataSimple.html
[`Request::get_param()`]: https://api.rocket.rs/v0.4/rocket/struct.Request.html#method.get_param
[`Request::get_segments()`]: https://api.rocket.rs/v0.4/rocket/struct.Request.html#method.get_segments
[`FormItem`]: https://api.rocket.rs/v0.4/rocket/request/struct.FormItem.html
[`rocket_contrib`]: https://api.rocket.rs/v0.4/rocket_contrib/index.html
[`MsgPack`]: https://api.rocket.rs/v0.4/rocket_contrib/msgpack/struct.MsgPack.html
[`Status::new()`]: https://api.rocket.rs/v0.4/rocket/http/struct.Status.html#method.new
[`Config`]: https://api.rocket.rs/v0.4/rocket/struct.Config.html
[`Config::root()`]: https://api.rocket.rs/v0.4/rocket/struct.Config.html#method.root

## General Improvements

In addition to new features, Rocket saw the following improvements:

  * Log messages now refer to routes by name.
  * Collision errors on launch name the colliding routes.
  * Launch fairing failures refer to the failing fairing by name.
  * The default `403` catcher now references authorization, not authentication.
  * Private cookies are set to `HttpOnly` and are given an expiration date of 1
    week by default.
  * A [Tera templates example] was added.
  * All macros, derives, and attributes are individually documented in
    [`rocket_codegen`].
  * Invalid client requests receive a response of `400` instead of `500`.
  * Response bodies are reliably stripped on `HEAD` requests.
  * Added a default catcher for `504: Gateway Timeout`.
  * Configuration information is logged in all environments.
  * Use of `unsafe` was reduced from 9 to 2 in core library.
  * [`FormItems`] now parses empty keys and values as well as keys without
    values.
  * Added [`Config::active()`] as a shorthand for
    `Config::new(Environment::active()?)`.
  * Address/port binding errors at launch are detected and explicitly emitted.
  * [`Flash`] cookies are cleared only after they are inspected.
  * `Sync` bound on [`AdHoc::on_attach()`], [`AdHoc::on_launch()`] was removed.
  * [`AdHoc::on_attach()`], [`AdHoc::on_launch()`] accept an `FnOnce`.
  * Added [`Config::root_relative()`] for retrieving paths relative to the
    configuration file.
  * Added [`Config::tls_enabled()`] for determining whether TLS is actively
    enabled.
  * ASCII color codes are not emitted on versions of Windows that do not support
    them.
  * Added FLAC (`audio/flac`), Icon (`image/x-icon`), WEBA (`audio/webm`), TIFF
    (`image/tiff`), AAC (`audio/aac`), Calendar (`text/calendar`), MPEG
    (`video/mpeg`), TAR (`application/x-tar`), GZIP (`application/gzip`), MOV
    (`video/quicktime`), MP4 (`video/mp4`), ZIP (`application/zip`) as known
    media types.
  * Added `.weba` (`WEBA`), `.ogv` (`OGG`), `.mp4` (`MP4`), `.mpeg4` (`MP4`),
    `.aac` (`AAC`), `.ics` (`Calendar`), `.bin` (`Binary`), `.mpg` (`MPEG`),
    `.mpeg` (`MPEG`), `.tar` (`TAR`), `.gz` (`GZIP`), `.tif` (`TIFF`), `.tiff`
    (`TIFF`), `.mov` (`MOV`) as known extensions.
  * Interaction between route attributes and declarative macros has been
    improved.
  * Generated code now logs through logging infrastructures as opposed to using
    `println!`.
  * Routing has been optimized by caching routing metadata.
  * [`Form`] and [`LenientForm`] can be publicly constructed.
  * Console coloring uses default terminal colors instead of white.
  * Console coloring is consistent across all messages.
  * `i128` and `u128` now implement [`FromParam`], [`FromFormValue`].
  * The `base64` dependency was updated to `0.10`.
  * The `log` dependency was updated to `0.4`.
  * The `handlebars` dependency was updated to `1.0`.
  * The `tera` dependency was updated to `0.11`.
  * The `uuid` dependency was updated to `0.7`.
  * The `rustls` dependency was updated to `0.14`.
  * The `cookie` dependency was updated to `0.11`.

[Tera templates example]: https://github.com/SergioBenitez/Rocket/tree/v0.4/examples/tera_templates
[`FormItems`]: https://api.rocket.rs/v0.4/rocket/request/enum.FormItems.html
[`Config::active()`]: https://api.rocket.rs/v0.4/rocket/config/struct.Config.html#method.active
[`Flash`]: https://api.rocket.rs/v0.4/rocket/response/struct.Flash.html
[`AdHoc::on_attach()`]: https://api.rocket.rs/v0.4/rocket/fairing/struct.AdHoc.html#method.on_attach
[`AdHoc::on_launch()`]: https://api.rocket.rs/v0.4/rocket/fairing/struct.AdHoc.html#method.on_launch
[`Config::root_relative()`]: https://api.rocket.rs/v0.4/rocket/struct.Config.html#method.root_relative
[`Config::tls_enabled()`]: https://api.rocket.rs/v0.4/rocket/struct.Config.html#method.tls_enabled
[`rocket_codegen`]: https://api.rocket.rs/v0.4/rocket_codegen/index.html
[`FromParam`]: https://api.rocket.rs/v0.4/rocket/request/trait.FromParam.html
[`FromFormValue`]: https://api.rocket.rs/v0.4/rocket/request/trait.FromFormValue.html
[`Data`]: https://api.rocket.rs/v0.4/rocket/struct.Data.html

## Infrastructure

  * All documentation is versioned.
  * Previous, current, and development versions of all documentation are hosted.
  * The repository was reorganized with top-level directories of `core` and
    `contrib`.
  * The `http` module was split into its own `rocket_http` crate. This is an
    internal change only.
  * All uses of `unsafe` are documented with informal proofs of correctness.

# Version 0.3.16 (Aug 24, 2018)

## Codegen

  * Codegen was updated for `2018-08-23` nightly.
  * Minimum required `rustc` is `1.30.0-nightly 2018-08-23`.

## Core

  * Force close only the read end of connections. This allows responses to be
    sent even when the client transmits more data than expected.

## Docs

  * Add details on retrieving configuration extras to guide.

# Version 0.3.15 (Jul 16, 2018)

## Codegen

  * The `#[catch]` decorator and `catchers!` macro were introduced, replacing
    `#[error]` and `errors!`.
  * The `#[error]` decorator and `errors!` macro were deprecated.
  * Codegen was updated for `2018-07-15` nightly.
  * Minimum required `rustc` is `1.29.0-nightly 2018-07-15`.

# Version 0.3.14 (Jun 22, 2018)

## Codegen

  * Codegen was updated for `2018-06-22` nightly.
  * Minimum required `rustc` is `1.28.0-nightly 2018-06-22`.

# Version 0.3.13 (Jun 16, 2018)

## Codegen

  * Codegen was updated for `2018-06-12` nightly.
  * Minimum required `rustc` is `1.28.0-nightly 2018-06-12`.

# Version 0.3.12 (May 31, 2018)

## Codegen

  * Codegen was updated for `2018-05-30` nightly.
  * Minimum required `rustc` is `1.28.0-nightly 2018-05-30`.

# Version 0.3.11 (May 19, 2018)

## Core

  * Core was updated for `2018-05-18` nightly.

## Infrastructure

  * Fixed injection of dependencies for codegen compile-fail tests.

# Version 0.3.10 (May 05, 2018)

## Core

  * Fixed parsing of nested TOML structures in config environment variables.

## Codegen

  * Codegen was updated for `2018-05-03` nightly.
  * Minimum required `rustc` is `1.27.0-nightly 2018-05-04`.

## Contrib

  * Contrib was updated for `2018-05-03` nightly.

## Docs

  * Fixed database pool type in state guide.

# Version 0.3.9 (Apr 26, 2018)

## Core

  * Core was updated for `2018-04-26` nightly.
  * Minimum required `rustc` is `1.27.0-nightly 2018-04-26`.
  * Managed state retrieval cost was reduced to an unsynchronized `HashMap`
    lookup.

## Codegen

  * Codegen was updated for `2018-04-26` nightly.
  * Minimum required `rustc` is `1.27.0-nightly 2018-04-26`.

## Contrib

  * A 512-byte buffer is preallocated when deserializing JSON, improving
    performance.

## Docs

  * Fixed various typos in rustdocs and guide.

# Version 0.3.8 (Apr 07, 2018)

## Codegen

  * Codegen was updated for `2018-04-06` nightly.
  * Minimum required `rustc` is `1.27.0-nightly 2018-04-06`.

# Version 0.3.7 (Apr 03, 2018)

## Core

  * Fixed a bug where incoming request URIs would match routes with the same
    path prefix and suffix and ignore the rest.
  * Added known media types for WASM, WEBM, OGG, and WAV.
  * Fixed fragment URI parsing.

## Codegen

  * Codegen was updated for `2018-04-03` nightly.
  * Minimum required `rustc` is `1.27.0-nightly 2018-04-03`.

## Contrib

  * JSON data is read eagerly, improving deserialization performance.

## Docs

  * Database example and docs were updated for Diesel 1.1.
  * Removed outdated README performance section.
  * Fixed various typos in rustdocs and guide.

## Infrastructure

  * Removed gates for stabilized features: `iterator_for_each`, `i128_type`,
    `conservative_impl_trait`, `never_type`.
  * Travis now tests in both debug and release mode.

# Version 0.3.6 (Jan 12, 2018)

## Core

  * `Rocket.state()` method was added to retrieve managed state from `Rocket`
    instances.
  * Nested calls to `Rocket.attach()` are now handled correctly.
  * JSON API (`application/vnd.api+json`) is now a known media type.
  * Uncached markers for `ContentType` and `Accept` headers are properly
    preserved on `Request.clone()`.
  * Minimum required `rustc` is `1.25.0-nightly 2018-01-12`.

## Codegen

  * Codegen was updated for `2017-12-22` nightly.
  * Minimum required `rustc` is `1.24.0-nightly 2017-12-22`.

## Docs

  * Fixed typo in state guide: ~~simple~~ simply.
  * Database example and docs were updated for Diesel 1.0.

## Infrastructure

  * Shell scripts now use `git grep` instead of `egrep` for faster searching.

# Version 0.3.5 (Dec 18, 2017)

## Codegen

  * Codegen was updated for `2017-12-17` nightly.
  * Minimum required `rustc` is `1.24.0-nightly 2017-12-17`.

# Version 0.3.4 (Dec 14, 2017)

## Core

  * `NamedFile`'s `Responder` implementation now uses a sized body when the
    file's length is known.
  * `#[repr(C)]` is used on `str` wrappers to guarantee correct structure layout
    across platforms.
  * A `status::BadRequest` `Responder` was added.

## Codegen

  * Codegen was updated for `2017-12-13` nightly.
  * Minimum required `rustc` is `1.24.0-nightly 2017-12-13`.

## Docs

  * The rustdoc `html_root_url` now points to the correct address.
  * Fixed typo in fairings guide: ~~event~~ events.
  * Fixed typo in `Outcome` docs: ~~users~~ Users.

# Version 0.3.3 (Sep 25, 2017)

## Core

  * `Config`'s `Debug` implementation now respects formatting options.
  * `Cow<str>` now implements `FromParam`.
  * `Vec<u8>` now implements `Responder`.
  * Added a `Binary` media type for `application/octet-stream`.
  * Empty fairing collections are no longer logged.
  * Emojis are no longer emitted to non-terminals.
  * Minimum required `rustc` is `1.22.0-nightly 2017-09-13`.

## Codegen

  * Improved "missing argument in handler" compile-time error message.
  * Codegen was updated for `2017-09-25` nightly.
  * Minimum required `rustc` is `1.22.0-nightly 2017-09-25`.

## Docs

  * Fixed typos in site overview: ~~by~~ be, ~~`Reponder`~~ `Responder`.
  * Markdown indenting was adjusted for CommonMark.

## Infrastructure

  * Shell scripts handle paths with spaces.

# Version 0.3.2 (Aug 15, 2017)

## Core

  * Added conversion methods from and to `Box<UncasedStr>`.

## Codegen

  * Lints were removed due to compiler instability. Lints will likely return as
    a separate `rocket_lints` crate.

# Version 0.3.1 (Aug 11, 2017)

## Core

  * Added support for ASCII colors on modern Windows consoles.
  * Form field renames can now include _any_ valid characters, not just idents.

## Codegen

  * Ignored named route parameters are now allowed (`_ident`).
  * Fixed issue where certain paths would cause a lint `assert!` to fail
    ([#367](https://github.com/SergioBenitez/Rocket/issues/367)).
  * Lints were updated for `2017-08-10` nightly.
  * Minimum required `rustc` is `1.21.0-nightly (2017-08-10)`.

## Contrib

  * Tera errors that were previously skipped internally are now emitted.

## Documentation

  * Typos were fixed across the board.

# Version 0.3.0 (Jul 14, 2017)

## New Features

This release includes the following new features:

  * [Fairings], Rocket's structure middleware, were introduced.
  * [Native TLS support] was introduced.
  * [Private cookies] were introduced.
  * A [`MsgPack`] type has been added to [`contrib`] for simple consumption and
    returning of MessagePack data.
  * Launch failures ([`LaunchError`]) from [`Rocket::launch()`] are now returned
    for inspection without panicking.
  * Routes without query parameters now match requests with or without query
    parameters.
  * [Default rankings] range from -4 to -1, preferring static paths and routes
    with query string matches.
  * A native [`Accept`] header structure was added.
  * The [`Accept`] request header can be retrieved via [`Request::accept()`].
  * Incoming form fields [can be renamed] via a new `#[form(field = "name")]`
    structure field attribute.
  * All active routes can be retrieved via [`Rocket::routes()`].
  * [`Response::body_string()`] was added to retrieve the response body as a
    `String`.
  * [`Response::body_bytes()`] was added to retrieve the response body as a
    `Vec<u8>`.
  * [`Response::content_type()`] was added to easily retrieve the Content-Type
    header of a response.
  * Size limits on incoming data are [now
    configurable](https://rocket.rs/v0.3/guide/configuration/#data-limits).
  * [`Request::limits()`] was added to retrieve incoming data limits.
  * Responders may dynamically adjust their response based on the incoming
    request.
  * [`Request::guard()`] was added for simple retrieval of request guards.
  * [`Request::route()`] was added to retrieve the active route, if any.
  * `&Route` is now a request guard.
  * The base mount path of a [`Route`] can be retrieved via `Route::base` or
    `Route::base()`.
  * [`Cookies`] supports _private_ (authenticated encryption) cookies, encrypted
    with the `secret_key` config key.
  * `Config::{development, staging, production}` constructors were added for
    [`Config`].
  * [`Config::get_datetime()`] was added to retrieve an extra as a `Datetime`.
  * Forms can be now parsed _leniently_ via the new [`LenientForm`] data guard.
  * The `?` operator can now be used with `Outcome`.
  * Quoted string, array, and table  based [configuration parameters] can be set
    via environment variables.
  * Log coloring is disabled when `stdout` is not a TTY.
  * [`FromForm`] is implemented for `Option<T: FromForm>`, `Result<T: FromForm,
    T::Error>`.
  * The [`NotFound`] responder was added for simple **404** response
    construction.

[Fairings]: https://rocket.rs/v0.3/guide/fairings/
[Native TLS support]: https://rocket.rs/v0.3/guide/configuration/#configuring-tls
[Private cookies]: https://rocket.rs/v0.3/guide/requests/#private-cookies
[can be renamed]: https://rocket.rs/v0.3/guide/requests/#field-renaming
[`MsgPack`]: https://api.rocket.rs/v0.3/rocket_contrib/struct.MsgPack.html
[`Rocket::launch()`]: https://api.rocket.rs/v0.3/rocket/struct.Rocket.html#method.launch
[`LaunchError`]: https://api.rocket.rs/v0.3/rocket/error/struct.LaunchError.html
[Default rankings]: https://api.rocket.rs/v0.3/rocket/struct.Route.html
[`Route`]: https://api.rocket.rs/v0.3/rocket/struct.Route.html
[`Accept`]: https://api.rocket.rs/v0.3/rocket/http/struct.Accept.html
[`Request::accept()`]: https://api.rocket.rs/v0.3/rocket/struct.Request.html#method.accept
[`contrib`]: https://api.rocket.rs/v0.3/rocket_contrib/
[`Rocket::routes()`]: https://api.rocket.rs/v0.3/rocket/struct.Rocket.html#method.routes
[`Response::body_string()`]: https://api.rocket.rs/v0.3/rocket/struct.Response.html#method.body_string
[`Response::body_bytes()`]: https://api.rocket.rs/v0.3/rocket/struct.Response.html#method.body_bytes
[`Response::content_type()`]: https://api.rocket.rs/v0.3/rocket/struct.Response.html#method.content_type
[`Request::guard()`]: https://api.rocket.rs/v0.3/rocket/struct.Request.html#method.guard
[`Request::limits()`]: https://api.rocket.rs/v0.3/rocket/struct.Request.html#method.limits
[`Request::route()`]: https://api.rocket.rs/v0.3/rocket/struct.Request.html#method.route
[`Config`]: https://api.rocket.rs/v0.3/rocket/struct.Config.html
[`Cookies`]: https://api.rocket.rs/v0.3/rocket/http/enum.Cookies.html
[`Config::get_datetime()`]: https://api.rocket.rs/v0.3/rocket/struct.Config.html#method.get_datetime
[`LenientForm`]: https://api.rocket.rs/v0.3/rocket/request/struct.LenientForm.html
[configuration parameters]: https://api.rocket.rs/v0.3/rocket/config/index.html#environment-variables
[`NotFound`]: https://api.rocket.rs/v0.3/rocket/response/status/struct.NotFound.html

## Breaking Changes

This release includes many breaking changes. These changes are listed below
along with a short note about how to handle the breaking change in existing
applications.

  * **`session_key` was renamed to `secret_key`, requires a 256-bit base64 key**

    It's unlikely that `session_key` was previously used. If it was, rename
    `session_key` to `secret_key`. Generate a random 256-bit base64 key using a
    tool like openssl: `openssl rand -base64 32`.

  * **The `&Cookies` request guard has been removed in favor of `Cookies`**

    Change `&Cookies` in a request guard position to `Cookies`.

  * **`Rocket::launch()` now returns a `LaunchError`, doesn't panic.**

    For the old behavior, suffix a call to `.launch()` with a semicolon:
    `.launch();`.

  * **Routes without query parameters match requests with or without query
    parameters.**

    There is no workaround, but this change may allow manual ranks from routes
    to be removed.

  * **The `format` route attribute on non-payload requests matches against the
    Accept header.**

    Excepting a custom request guard, there is no workaround. Previously,
    `format` always matched against the Content-Type header, regardless of
    whether the request method indicated a payload or not.

  * **A type of `&str` can no longer be used in form structures or parameters.**

    Use the new [`&RawStr`] type instead.

  * **`ContentType` is no longer a request guard.**

    Use `&ContentType` instead.

  * **`Request::content_type()` returns `&ContentType` instead of
    `ContentType`.**

    Use `.clone()` on `&ContentType` if a type of `ContentType` is required.

  * **`Response::header_values()` was removed. `Response::headers()` now returns
    an `&HeaderMap`.**

    A call to `Response::headers()` can be replaced with
    `Response::headers().iter()`. A call to `Response::header_values(name)` can
    be replaced with `Response::headers().get(name)`.

  * **Route collisions result in a hard error and panic.**

    There is no workaround. Previously, route collisions were a warning.

  * **The [`IntoOutcome`] trait has been expanded and made more flexible.**

    There is no workaround. `IntoOutcome::into_outcome()` now takes a `Failure`
    value to use. `IntoOutcome::or_forward()` was added to return a `Forward`
    outcome if `self` indicates an error.

  * **The 'testing' feature was removed.**

    Remove `features = ["testing"]` from `Cargo.toml`. Use the new [`local`]
    module for testing.

  * **`serde` was updated to 1.0.**

    There is no workaround. Ensure all dependencies rely on `serde` `1.0`.

  * **`config::active()` was removed.**

    Use [`Rocket::config()`] to retrieve the configuration before launch. If
    needed, use [managed state] to store config information for later use.

  * **The [`Responder`] trait has changed.**

    `Responder::respond(self)` was removed in favor of
    `Responder::respond_to(self, &Request)`. Responders may dynamically adjust
    their response based on the incoming request.

  * **`Outcome::of(Responder)` was removed while `Outcome::from(&Request,
    Responder)` was added.**

    Use `Outcome::from(..)` instead of `Outcome::of(..)`.

  * **Usage of templates requires `Template::fairing()` to be attached.**

    Call `.attach(Template::fairing())` on the application's Rocket instance
    before launching.

  * **The `Display` implementation of `Template` was removed.**

    Use [`Template::show()`] to render a template directly.

  * **`Request::new()` is no longer exported.**

    There is no workaround.

  * **The [`FromForm`] trait has changed.**

    `Responder::from_form_items(&mut FormItems)` was removed in favor of
    `Responder::from_form(&mut FormItems, bool)`. The second parameter indicates
    whether parsing should be strict (if `true`) or lenient (if `false`).

  * **`LoggingLevel` was removed as a root reexport.**

    It can now be imported from `rocket::config::LoggingLevel`.

  * **An `Io` variant was added to [`ConfigError`].**

    Ensure `match`es on `ConfigError` include an `Io` variant.

  * **[`ContentType::from_extension()`] returns an `Option<ContentType>`.**

    For the old behavior, use `.unwrap_or(ContentType::Any)`.

  * **The `IntoValue` config trait was removed in favor of `Into<Value>`.**

    There is no workaround. Use `Into<Value>` as necessary.

  * **The `rocket_contrib::JSON` type has been renamed to
    [`rocket_contrib::Json`].**

    Use `Json` instead of `JSON`.

  * **All structs in the [`content`] module use TitleCase names.**

    Use `Json`, `Xml`, `Html`, and `Css` instead of `JSON`, `XML`, `HTML`, and
    `CSS`, respectively.

[`&RawStr`]: https://api.rocket.rs/v0.3/rocket/http/struct.RawStr.html
[`IntoOutcome`]: https://api.rocket.rs/v0.3/rocket/outcome/trait.IntoOutcome.html
[`local`]: https://api.rocket.rs/v0.3/rocket/local/index.html
[`Rocket::config()`]: https://api.rocket.rs/v0.3/rocket/struct.Rocket.html#method.config
[managed state]: https://rocket.rs/v0.3/guide/state/
[`Responder`]: https://api.rocket.rs/v0.3/rocket/response/trait.Responder.html
[`Template::show()`]: https://api.rocket.rs/v0.3/rocket_contrib/struct.Template.html#method.show
[`FromForm`]: https://api.rocket.rs/v0.3/rocket/request/trait.FromForm.html
[`ConfigError`]: https://api.rocket.rs/v0.3/rocket/config/enum.ConfigError.html
[`ContentType::from_extension()`]: https://api.rocket.rs/v0.3/rocket/http/struct.ContentType.html#method.from_extension
[`rocket_contrib::Json`]: https://api.rocket.rs/v0.3/rocket_contrib/struct.Json.html
[`content`]: https://api.rocket.rs/v0.3/rocket/response/content/index.html

## General Improvements

In addition to new features, Rocket saw the following improvements:

  * "Rocket" is now capitalized in the `Server` HTTP header.
  * The generic parameter of `rocket_contrib::Json` defaults to `json::Value`.
  * The trailing '...' in the launch message was removed.
  * The launch message prints regardless of the config environment.
  * For debugging, `FromData` is implemented for `Vec<u8>` and `String`.
  * The port displayed on launch is the port resolved, not the one configured.
  * The `uuid` dependency was updated to `0.5`.
  * The `base64` dependency was updated to `0.6`.
  * The `toml` dependency was updated to `0.4`.
  * The `handlebars` dependency was updated to `0.27`.
  * The `tera` dependency was updated to `0.10`.
  * [`yansi`] is now used for all terminal coloring.
  * The `dev` `rustc` release channel is supported during builds.
  * [`Config`] is now exported from the root.
  * [`Request`] implements `Clone` and `Debug`.
  * The `workers` config parameter now defaults to `num_cpus * 2`.
  * Console logging for table-based config values is improved.
  * `PartialOrd`, `Ord`, and `Hash` are now implemented for [`State`].
  * The format of a request is always logged when available.
  * Route matching on `format` now functions as documented.

[`yansi`]: https://crates.io/crates/yansi
[`Request`]: https://api.rocket.rs/v0.3/rocket/struct.Request.html
[`State`]: https://api.rocket.rs/v0.3/rocket/struct.State.html

## Infrastructure

  * All examples include a test suite.
  * The `master` branch now uses a `-dev` version number.

# Version 0.2.8 (Jun 01, 2017)

## Codegen

  * Lints were updated for `2017-06-01` nightly.
  * Minimum required `rustc` is `1.19.0-nightly (2017-06-01)`.

# Version 0.2.7 (May 26, 2017)

## Codegen

  * Codegen was updated for `2017-05-26` nightly.

# Version 0.2.6 (Apr 17, 2017)

## Codegen

  * Allow `k` and `v` to be used as fields in `FromForm` structures by avoiding
    identifier collisions ([#265]).

[#265]: https://github.com/SergioBenitez/Rocket/issues/265

# Version 0.2.5 (Apr 16, 2017)

## Codegen

  * Lints were updated for `2017-04-15` nightly.
  * Minimum required `rustc` is `1.18.0-nightly (2017-04-15)`.

# Version 0.2.4 (Mar 30, 2017)

## Codegen

  * Codegen was updated for `2017-03-30` nightly.
  * Minimum required `rustc` is `1.18.0-nightly (2017-03-30)`.

# Version 0.2.3 (Mar 22, 2017)

## Fixes

  * Multiple header values for the same header name are now properly preserved
    (#223).

## Core

  * The `get_slice` and `get_table` methods were added to `Config`.
  * The `pub_restricted` feature has been stabilized!

## Codegen

  * Lints were updated for `2017-03-20` nightly.
  * Minimum required `rustc` is `1.17.0-nightly (2017-03-22)`.

## Infrastructure

  * The test script now denies trailing whitespace.

# Version 0.2.2 (Feb 26, 2017)

## Codegen

  * Lints were updated for `2017-02-25`  and `2017-02-26` nightlies.
  * Minimum required `rustc` is `1.17.0-nightly (2017-02-26)`.

# Version 0.2.1 (Feb 24, 2017)

## Core Fixes

  * `Flash` cookie deletion functions as expected regardless of the path.
  * `config` properly accepts IPv6 addresses.
  * Multiple `Set-Cookie` headers are properly set.

## Core Improvements

  * `Display` and `Error` were implemented for `ConfigError`.
  * `webp`, `ttf`, `otf`, `woff`, and `woff2` were added as known content types.
  * Routes are presorted for faster routing.
  * `into_bytes` and `into_inner` methods were added to `Body`.

## Codegen

  * Fixed `unmanaged_state` lint so that it works with prefilled type aliases.

## Contrib

  * Better errors are emitted on Tera template parse errors.

## Documentation

  * Fixed typos in `manage` and `JSON` docs.

## Infrastructure

  * Updated doctests for latest Cargo nightly.

# Version 0.2.0 (Feb 06, 2017)

Detailed release notes for v0.2 can also be found on
[rocket.rs](https://rocket.rs/v0.3/news/2017-02-06-version-0.2/).

## New Features

This release includes the following new features:

  * Introduced managed state.
  * Added lints that warn on unmanaged state and unmounted routes.
  * Added the ability to set configuration parameters via environment variables.
  * `Config` structures can be built via `ConfigBuilder`, which follows the
    builder pattern.
  * Logging can be enabled or disabled on custom configuration via a second
    parameter to the `Rocket::custom` method.
  * `name` and `value` methods were added to `Header` to retrieve the name and
    value of a header.
  * A new configuration parameter, `workers`, can be used to set the number of
    threads Rocket uses.
  * The address of the remote connection is available via `Request.remote()`.
    Request preprocessing overrides remote IP with value from the `X-Real-IP`
    header, if present.
  * During testing, the remote address can be set via `MockRequest.remote()`.
  * The `SocketAddr` request guard retrieves the remote address.
  * A `UUID` type has been added to `contrib`.
  * `rocket` and `rocket_codegen` will refuse to build with an incompatible
    nightly version and emit nice error messages.
  * Major performance and usability improvements were upstreamed to the `cookie`
    crate, including the addition of a `CookieBuilder`.
  * When a checkbox isn't present in a form, `bool` types in a `FromForm`
    structure will parse as `false`.
  * The `FormItems` iterator can be queried for a complete parse via `completed`
    and `exhausted`.
  * Routes for `OPTIONS` requests can be declared via the `options` decorator.
  * Strings can be percent-encoded via `URI::percent_encode()`.

## Breaking Changes

This release includes several breaking changes. These changes are listed below
along with a short note about how to handle the breaking change in existing
applications.

  * **`Rocket::custom` takes two parameters, the first being `Config` by
    value.**

    A call in v0.1 of the form `Rocket::custom(&config)` is now
    `Rocket::custom(config, false)`.

  * **Tera templates are named without their extension.**

    A templated named `name.html.tera` is now simply `name`.

  * **`JSON` `unwrap` method has been renamed to `into_inner`.**

    A call to `.unwrap()` should be changed to `.into_inner()`.

  * **The `map!` macro was removed in favor of the `json!` macro.**

    A call of the form `map!{ "a" => b }` can be written as: `json!({ "a": b
    })`.

  * **The `hyper::SetCookie` header is no longer exported.**

    Use the `Cookie` type as an `Into<Header>` type directly.

  * **The `Content-Type` for `String` is now `text/plain`.**

    Use `content::HTML<String>` for HTML-based `String` responses.

  * **`Request.content_type()` returns an `Option<ContentType>`.**

    Use `.unwrap_or(ContentType::Any)` to get the old behavior.

  * **The `ContentType` request guard forwards when the request has no
    `Content-Type` header.**

    Use an `Option<ContentType>` and `.unwrap_or(ContentType::Any)` for the old
    behavior.

  * **A `Rocket` instance must be declared _before_ a `MockRequest`.**

    Change the order of the `rocket::ignite()` and `MockRequest::new()` calls.

  * **A route with `format` specified only matches requests with the same
    format.**

    Previously, a route with a `format` would match requests without a format
    specified. There is no workaround to this change; simply specify formats
    when required.

  * **`FormItems` can no longer be constructed directly.**

    Instead of constructing as `FormItems(string)`, construct as
    `FormItems::from(string)`.

  * **`from_from_string(&str)` in `FromForm` removed in favor of
    `from_form_items(&mut FormItems)`.**

    Most implementation should be using `FormItems` internally; simply use the
    passed in `FormItems`. In other cases, the form string can be retrieved via
    the `inner_str` method of `FormItems`.

  * **`Config::{set, default_for}` are deprecated.**

    Use the `set_{param}` methods instead of `set`, and `new` or `build` in
    place of `default_for`.

  * **Route paths must be absolute.**

    Prepend a `/` to convert a relative path into an absolute one.

  * **Route paths cannot contain empty segments.**

    Remove any empty segments, including trailing ones, from a route path.

## Bug Fixes

A couple of bugs were fixed in this release:

  * Handlebars partials were not properly registered
    ([#122](https://github.com/SergioBenitez/Rocket/issues/122)).
  * `Rocket::custom` did not set the custom configuration as the `active`
    configuration.
  * Route path segments containing more than one dynamic parameter were
    allowed.

## General Improvements

In addition to new features, Rocket saw the following smaller improvements:

  * Rocket no longer overwrites a catcher's response status.
  * The `port` `Config` type is now a proper `u16`.
  * Clippy issues injected by codegen are resolved.
  * Handlebars was updated to `0.25`.
  * The `PartialEq` implementation of `Config` doesn't consider the path or
    secret key.
  * Hyper dependency updated to `0.10`.
  * The `Error` type for `JSON as FromData` has been exposed as `SerdeError`.
  * SVG was added as a known Content-Type.
  * Serde was updated to `0.9`.
  * Form parse failure now results in a **422** error code.
  * Tera has been updated to `0.7`.
  * `pub(crate)` is used throughout to enforce visibility rules.
  * Query parameters in routes (`/path?<param>`) are now logged.
  * Routes with and without query parameters no longer _collide_.

## Infrastructure

  * Testing was parallelized, resulting in 3x faster Travis builds.

# Version 0.1.6 (Jan 26, 2017)

## Infrastructure

  * Hyper version pinned to 0.9.14 due to upstream non-semver breaking change.

# Version 0.1.5 (Jan 14, 2017)

## Core

  * Fixed security checks in `FromSegments` implementation for `PathBuf`.

## Infrastructure

  * `proc_macro` feature removed from examples due to stability.

# Version 0.1.4 (Jan 4, 2017)

## Core

  * Header names are treated as case-preserving.

## Codegen

  * Minimum supported nightly is `2017-01-03`.

# Version 0.1.3 (Dec 31, 2016)

## Core

  * Typo in `Outcome` formatting fixed (Succcess -> Success).
  * Added `ContentType::CSV`.
  * Dynamic segments parameters are properly resolved, even when mounted.
  * Request methods are only overridden via `_method` field on POST.
  * Form value `String`s are properly decoded.

## Codegen

  * The `_method` field is now properly ignored in `FromForm` derivation.
  * Unknown Content-Types in `format` no longer result in an error.
  * Deriving `FromForm` no longer results in a deprecation warning.
  * Codegen will refuse to build with incompatible rustc, presenting error
    message and suggestion.
  * Added `head` as a valid decorator for `HEAD` requests.
  * Added `route(OPTIONS)` as a valid decorator for `OPTIONS` requests.

## Contrib

  * Templates with the `.tera` extension are properly autoescaped.
  * Nested template names are properly resolved on Windows.
  * Template implements `Display`.
  * Tera dependency updated to version 0.6.

## Docs

  * Todo example requirements clarified in its `README`.

## Testing

  * Tests added for `config`, `optional_result`, `optional_redirect`, and
    `query_params` examples.
  * Testing script checks for and disallows tab characters.

## Infrastructure

  * New script (`bump_version.sh`) automates version bumps.
  * Config script emits error when readlink/readpath support is bad.
  * Travis badge points to public builds.

# Version 0.1.2 (Dec 24, 2016)

## Codegen

  * Fix `get_raw_segments` index argument in route codegen
    ([#41](https://github.com/SergioBenitez/Rocket/issues/41)).
  * Segments params (`<param..>`) respect prefixes.

## Contrib

  * Fix nested template name resolution
    ([#42](https://github.com/SergioBenitez/Rocket/issues/42)).

## Infrastructure

  * New script (`publish.sh`) automates publishing to crates.io.
  * New script (`bump_version.sh`) automates version bumps.

# Version 0.1.1 (Dec 23, 2016)

## Core

  * `NamedFile` `Responder` lost its body in the shuffle; it's back!

# Version 0.1.0 (Dec 23, 2016)

This is the first public release of Rocket!

## Breaking

All of the mentions to `hyper` types in core Rocket types are no more. Rocket
now implements its own `Request` and `Response` types.

  * `ContentType` uses associated constants instead of static methods.
  * `StatusCode` removed in favor of new `Status` type.
  * `Response` type alias superseded by `Response` type.
  * `Responder::respond` no longer takes in hyper type.
  * `Responder::respond` returns `Response`, takes `self` by move.
  * `Handler` returns `Outcome` instead of `Response` type alias.
  * `ErrorHandler` returns `Result`.
  * All `Hyper*` types were moved to unprefixed versions in `hyper::`.
  * `MockRequest::dispatch` now returns a `Response` type.
  * `URIBuf` removed in favor of unified `URI`.
  * Rocket panics when an illegal, dynamic mount point is used.

## Core

  * Rocket handles `HEAD` requests automatically.
  * New `Response` and `ResponseBuilder` types.
  * New `Request`, `Header`, `Status`, and `ContentType` types.

## Testing

  * `MockRequest` allows any type of header.
  * `MockRequest` allows cookies.

## Codegen

  * Debug output disabled by default.
  * The `ROCKET_CODEGEN_DEBUG` environment variables enables codegen logging.

# Version 0.0.11 (Dec 11, 2016)

## Streaming Requests

All incoming request data is now streamed. This resulted in a major change to
the Rocket APIs. They are summarized through the following API changes:

  * The `form` route parameter has been removed.
  * The `data` route parameter has been introduced.
  * Forms are now handled via the `data` parameter and `Form` type.
  * Removed the `data` parameter from `Request`.
  * Added `FromData` conversion trait and default implementation.
  * `FromData` is used to automatically derive the `data` parameter.
  * `Responder`s are now final: they cannot forward to other requests.
  * `Responder`s may only forward to catchers.

## Breaking

  * Request `uri` parameter is private. Use `uri()` method instead.
  * `form` module moved under `request` module.
  * `response::data` was renamed to `response::content`.
  * Introduced `Outcome` with `Success`, `Failure`, and `Forward` variants.
  * `outcome` module moved to top-level.
  * `Response` is now a type alias to `Outcome`.
  * `Empty` `Responder` was removed.
  * `StatusResponder` removed in favor of `response::status` module.

## Codegen

  * Error handlers can now take 0, 1, or 2 parameters.
  * `FromForm` derive now works on empty structs.
  * Lifetimes are now properly stripped in code generation.
  * Any valid ident is now allowed in single-parameter route parameters.

## Core

  * Route is now cloneable.
  * `Request` no longer has any lifetime parameters.
  * `Handler` type now includes a `Data` parameter.
  * `http` module is public.
  * `Responder` implemented for `()` type as an empty response.
  * Add `config::get()` for global config access.
  * Introduced `testing` module.
  * `Rocket.toml` allows global configuration via `[global]` table.

## Docs

  * Added a `raw_upload` example.
  * Added a `pastebin` example.
  * Documented all public APIs.

## Testing

  * Now building and running tests with `--all-features` flag.
  * Added appveyor config for Windows CI testing.

# Version 0.0.10 (Oct 03, 2016)

## Breaking

  * Remove `Rocket::new` in favor of `ignite` method.
  * Remove `Rocket::mount_and_launch` in favor of chaining `mount(..).launch()`.
  * `mount` and `catch` take `Rocket` type by value.
  * All types related to HTTP have been moved into `http` module.
  * `Template::render` in `contrib` now takes context by reference.

## Core

  * Rocket now parses option `Rocket.toml` for configuration, defaulting to sane
    values.
  * `ROCKET_ENV` environment variable can be used to specify running environment.

## Docs

  * Document `ContentType`.
  * Document `Request`.
  * Add script that builds docs.

## Testing

  * Scripts can now be run from any directory.
  * Cache Cargo directories in Travis for faster testing.
  * Check that library version numbers match in testing script.

# Version 0.0.9 (Sep 29, 2016)

## Breaking

  * Rename `response::data_type` to `response::data`.

## Core

  * Rocket interprets `_method` field in forms as the incoming request's method.
  * Add `Outcome::Bad` to signify responses that failed internally.
  * Add a `NamedFile` `Responder` type that uses a file's extension for the
    response's content type.
  * Add a `Stream` `Responder` for streaming responses.

## Contrib

  * Introduce the `contrib` crate.
  * Add JSON support via `JSON`, which implements `FromRequest` and `Responder`.
  * Add templating support via `Template` which implements `Responder`.

## Docs

  * Initial guide-like documentation.
  * Add documentation, testing, and contributing sections to README.

## Testing

  * Add a significant number of codegen tests.