Revamp pastebin tutorial for Rocket v0.5.

Closes #1756.
This commit is contained in:
Sergio Benitez 2022-05-08 01:57:49 -05:00
parent 4c8bd61c4f
commit fccb5759db
5 changed files with 327 additions and 238 deletions

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@ -1,7 +1,8 @@
#[macro_use] extern crate rocket;
#[cfg(test)]
mod tests;
mod paste_id;
#[cfg(test)] mod tests;
use std::io;
@ -12,8 +13,8 @@ use rocket::tokio::fs::{self, File};
use crate::paste_id::PasteId;
// In a real application, these would be retrieved dynamically from a config.
const HOST: Absolute<'static> = uri!("http://localhost:8000");
const ID_LENGTH: usize = 3;
#[post("/", data = "<paste>")]
@ -53,6 +54,5 @@ fn index() -> &'static str {
#[launch]
fn rocket() -> _ {
rocket::build()
.mount("/", routes![index, upload, delete, retrieve])
rocket::build().mount("/", routes![index, upload, delete, retrieve])
}

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@ -1,12 +1,8 @@
use std::borrow::Cow;
use std::path::{Path, PathBuf};
use rocket::http::uri::fmt;
use rocket::request::FromParam;
use rand::{self, Rng};
/// Table to retrieve base62 values from.
const BASE62: &[u8] = b"0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
use rocket::request::FromParam;
/// A _probably_ unique paste ID.
#[derive(UriDisplayPath)]
@ -18,6 +14,8 @@ impl PasteId<'_> {
/// probability of a collision depends on the value of `size` and the number
/// of IDs generated thus far.
pub fn new(size: usize) -> PasteId<'static> {
const BASE62: &[u8] = b"0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
let mut id = String::with_capacity(size);
let mut rng = rand::thread_rng();
for _ in 0..size {
@ -27,6 +25,7 @@ impl PasteId<'_> {
PasteId(Cow::Owned(id))
}
/// Returns the path to the paste in `upload/` corresponding to this ID.
pub fn file_path(&self) -> PathBuf {
let root = concat!(env!("CARGO_MANIFEST_DIR"), "/", "upload");
Path::new(root).join(self.0.as_ref())
@ -44,11 +43,3 @@ impl<'a> FromParam<'a> for PasteId<'a> {
.ok_or(param)
}
}
impl<'a> fmt::FromUriParam<fmt::Path, &'a str> for PasteId<'_> {
type Target = PasteId<'a>;
fn from_uri_param(param: &'a str) -> Self::Target {
PasteId(param.into())
}
}

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@ -1,6 +1,7 @@
use super::{rocket, index, PasteId};
use rocket::local::blocking::Client;
use rocket::http::{Status, ContentType};
use rocket::request::FromParam;
fn extract_id(from: &str) -> Option<String> {
from.rfind('/').map(|i| &from[(i + 1)..]).map(|s| s.trim_end().to_string())
@ -25,6 +26,7 @@ fn upload_paste(client: &Client, body: &str) -> String {
}
fn download_paste(client: &Client, id: &str) -> Option<String> {
let id = PasteId::from_param(id).expect("valid ID");
let response = client.get(uri!(super::retrieve(id))).dispatch();
if response.status().class().is_success() {
Some(response.into_string().unwrap())
@ -34,6 +36,7 @@ fn download_paste(client: &Client, id: &str) -> Option<String> {
}
fn delete_paste(client: &Client, id: &str) {
let id = PasteId::from_param(id).expect("valid ID");
let response = client.delete(uri!(super::delete(id))).dispatch();
assert_eq!(response.status(), Status::Ok);
}

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@ -1,19 +1,22 @@
# Pastebin
# Pastebin Tutorial
To give you a taste of what a real Rocket application looks like, this section
of the guide is a tutorial on how to create a Pastebin application in Rocket. A
pastebin is a simple web application that allows users to upload a text document
and later retrieve it via a special URL. They're often used to share code
snippets, configuration files, and error logs. In this tutorial, we'll build a
simple pastebin service that allows users to upload a file from their terminal.
The service will respond back with a URL to the uploaded file.
This section of the guide is a tutorial intended to demonstrate how real-world
Rocket applications are crafted. We'll build a simple pastebin service that
allows users to upload a file from any HTTP client, including `curl`. The
service will respond back with a URL to the uploaded file.
! note: What's a pastebin?
A pastebin is a simple web application that allows users to upload a document
and later retrieve it via a special URL. They're often used to share code
snippets, configuration files, and error logs.
## Finished Product
A souped-up, completed version of the application you're about to build is
deployed live at [paste.rs](https://paste.rs). Feel free to play with the
application to get a feel for how it works. For example, to upload a text
document named `test.txt`, you can do:
document named `test.txt`, you can run:
```sh
curl --data-binary @test.txt https://paste.rs/
@ -22,12 +25,18 @@ curl --data-binary @test.txt https://paste.rs/
The finished product is composed of the following routes:
* index: **`GET /`** - returns a simple HTML page with instructions about how
to use the service
* upload: **`POST /`** - accepts raw data in the body of the request and
responds with a URL of a page containing the body's content
* retrieve: **`GET /<id>`** - retrieves the content for the paste with id
`<id>`
* `index` - `#[get("/")]`
returns a simple HTML page with instructions about how to use the service
* `upload` - `#[post("/")]`
accepts raw data in the body of the request and responds with a URL of a
page containing the body's content
* `retrieve` - `#[get("/<id>")]`
retrieves the content for the paste with id `<id>`
## Getting Started
@ -70,10 +79,10 @@ tutorial, we'll create the three routes and accompanying handlers.
## Index
The first route we'll create is the `index` route. This is the page users will
see when they first visit the service. As such, the route should field requests
of the form `GET /`. We declare the route and its handler by adding the `index`
function below to `src/main.rs`:
The first route we'll create is `index`. This is the page users will see when
they first visit the service. As such, the route should handle `GET /`. We
declare the route and its handler by adding the `index` function below to
`src/main.rs`:
```rust
# #[macro_use] extern crate rocket;
@ -98,9 +107,11 @@ fn index() -> &'static str {
This declares the `index` route for requests to `GET /` as returning a static
string with the specified contents. Rocket will take the string and return it as
the body of a fully formed HTTP response with `Content-Type: text/plain`. You
can read more about how Rocket formulates responses at the [API documentation
for the Responder
trait](@api/rocket/response/trait.Responder.html).
can read more about how Rocket formulates responses in the [responses section]
of the guide or at the [API documentation for the Responder
trait](@api/rocket/response/trait.Responder.html).
[responses section]: ../responses
Remember that routes first need to be mounted before Rocket dispatches requests
to them. To mount the `index` route, modify the main function so that it reads:
@ -116,199 +127,123 @@ fn rocket() -> _ {
```
You should now be able to `cargo run` the application and visit the root path
(`/`) to see the text being displayed.
(`/`) to see the text.
## Uploading
## Design
The most complicated aspect of the pastebin, as you might imagine, is handling
upload requests. When a user attempts to upload a pastebin, our service needs to
generate a unique ID for the upload, read the data, write it out to a file or
database, and then return a URL with the ID. We'll take each of these one step
at a time, beginning with generating IDs.
Before we continue, we'll need to make a few design decisions.
### Unique IDs
* **Where should pastes be stored?**
Generating a unique and useful ID is an interesting topic, but it is outside the
scope of this tutorial. Instead, we simply provide the code for a `PasteId`
structure that represents a _probably_ unique ID. Read through the code, then
copy/paste it into a new file named `paste_id.rs` in the `src/` directory:
To keep things simple, we'll store uploaded pastes on the file system inside
of an `upload/` directory. Let's create that directory next to `src/` in our
project now:
```rust
use std::fmt;
use std::borrow::Cow;
```sh
mkdir upload
```
use rand::{self, Rng};
Our project tree now looks like:
/// Table to retrieve base62 values from.
const BASE62: &[u8] = b"0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
```sh
.
├── Cargo.toml
├── src
│   └── main.rs
└── upload
```
/// A _probably_ unique paste ID.
pub struct PasteId<'a>(Cow<'a, str>);
* **What should we name the uploaded paste files?**
impl<'a> PasteId<'a> {
/// Generate a _probably_ unique ID with `size` characters. For readability,
/// the characters used are from the sets [0-9], [A-Z], [a-z]. The
/// probability of a collision depends on the value of `size` and the number
/// of IDs generated thus far.
pub fn new(size: usize) -> PasteId<'static> {
let mut id = String::with_capacity(size);
let mut rng = rand::thread_rng();
for _ in 0..size {
id.push(BASE62[rng.gen::<usize>() % 62] as char);
Similarly, we'll keep things simple by naming paste files a string of random
but readable characters. We'll call this random string the paste's "ID". To
represent, generate, and store the ID, we'll create a `PasteId` structure in
a new module file named `paste_id.rs` with the following contents:
```rust
use std::borrow::Cow;
use std::path::{Path, PathBuf};
use rand::{self, Rng};
/// A _probably_ unique paste ID.
pub struct PasteId<'a>(Cow<'a, str>);
impl PasteId<'_> {
/// Generate a _probably_ unique ID with `size` characters. For readability,
/// the characters used are from the sets [0-9], [A-Z], [a-z]. The
/// probability of a collision depends on the value of `size` and the number
/// of IDs generated thus far.
pub fn new(size: usize) -> PasteId<'static> {
const BASE62: &[u8] = b"0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
let mut id = String::with_capacity(size);
let mut rng = rand::thread_rng();
for _ in 0..size {
id.push(BASE62[rng.gen::<usize>() % 62] as char);
}
PasteId(Cow::Owned(id))
}
PasteId(Cow::Owned(id))
/// Returns the path to the paste in `upload/` corresponding to this ID.
pub fn file_path(&self) -> PathBuf {
let root = concat!(env!("CARGO_MANIFEST_DIR"), "/", "upload");
Path::new(root).join(self.0.as_ref())
}
}
}
```
```
Then, in `src/main.rs`, add the following after `extern crate rocket`:
We've given you the ID and path generation code for free. Our project tree
now looks like:
```rust
# /*
mod paste_id;
# */ mod paste_id { pub struct PasteId; }
```sh
.
├── Cargo.toml
├── src
│   ├── main.rs
│   └── paste_id.rs # new! contains `PasteId`
└── upload
```
use paste_id::PasteId;
```
We'll import the new module and struct in `src/main.rs`, after the `extern
crate rocket`:
Finally, add a dependency for the `rand` crate to the `Cargo.toml` file:
```rust
# /*
mod paste_id;
# */ mod paste_id { pub struct PasteId; }
```toml
[dependencies]
# existing Rocket dependencies...
rand = "0.8"
```
use crate::paste_id::PasteId;
```
Then, ensure that your application builds with the new code:
You'll notice that our code to generate paste IDs uses the `rand` crate, so
we'll need to add it as a dependency in our `Cargo.toml` file:
```sh
cargo build
```
```toml
[dependencies]
## existing Rocket dependencies...
rand = "0.8"
```
You'll likely see many "unused" warnings for the new code we've added: that's
okay and expected. We'll be using the new code soon.
Ensure that your application builds with the new code:
### Processing
```sh
cargo build
```
Believe it or not, the hard part is done! (_whew!_).
You'll likely see many "unused" warnings for the new code we've added: that's
okay and expected. We'll be using the new code soon.
To process the upload, we'll need a place to store the uploaded files. To
simplify things, we'll store the uploads in a directory named `upload/`. Create
an `upload` directory next to the `src` directory:
```sh
mkdir upload
```
For the `upload` route, we'll need to import `Data`:
```rust
use rocket::Data;
```
The [Data](@api/rocket/data/struct.Data.html) structure is key
here: it represents an unopened stream to the incoming request body data. We'll
use it to efficiently stream the incoming request to a file.
### Upload Route
We're finally ready to write the `upload` route. Before we show you the code,
you should attempt to write the route yourself. Here's a hint: a possible route
and handler signature look like this:
```rust
# #[macro_use] extern crate rocket;
use rocket::Data;
use rocket::response::Debug;
#[post("/", data = "<paste>")]
fn upload(paste: Data<'_>) -> std::io::Result<String> {
# unimplemented!()
/* .. */
}
```
Your code should:
1. Create a new `PasteId` of a length of your choosing.
2. Construct a filename inside `upload/` given the `PasteId`.
3. Stream the `Data` to the file with the constructed filename.
4. Construct a URL given the `PasteId`.
5. Return the URL to the client.
Here's our version (in `src/main.rs`):
```rust
# #[macro_use] extern crate rocket;
# fn main() {}
# use std::fmt;
# struct PasteId;
# impl PasteId { fn new(n: usize) -> Self { PasteId } }
# impl fmt::Display for PasteId {
# fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { Ok(()) }
# }
use rocket::response::Debug;
use rocket::data::{Data, ToByteUnit};
#[post("/", data = "<paste>")]
async fn upload(paste: Data<'_>) -> Result<String, Debug<std::io::Error>> {
let id = PasteId::new(3);
let filename = format!("upload/{id}", id = id);
let url = format!("{host}/{id}\n", host = "http://localhost:8000", id = id);
// Write the paste out, limited to 128KiB, and return the URL.
paste.open(128.kibibytes()).into_file(filename).await?;
Ok(url)
}
```
Note the [`kibibytes()`] method call: this method comes from the [`ToByteUnit`]
extension trait. Ensure that the route is mounted at the root path:
```rust
# #[macro_use] extern crate rocket;
# #[get("/")] fn index() {}
# #[post("/")] fn upload() {}
#[launch]
fn rocket() -> _ {
rocket::build().mount("/", routes![index, upload])
}
```
Test that your route works via `cargo run`. From a separate terminal, upload a
file using `curl`. Then verify that the file was saved to the `upload` directory
with the correct ID:
```sh
# in the project root
cargo run
# in a separate terminal
echo "Hello, world." | curl --data-binary @- http://localhost:8000
# => http://localhost:8000/eGs
# back to the terminal running the pastebin
<ctrl-c> # kill running process
ls upload # ensure the upload is there
cat upload/* # ensure that contents are correct
```
Note that since we haven't created a `GET /<id>` route, visiting the returned URL
will result in a **404**. We'll fix that now.
[`kibibytes()`]: @api/rocket/data/trait.ToByteUnit.html#tymethod.kibibytes
[`ToByteUnit`]: @api/rocket/data/trait.ToByteUnit.html
With these design decisions made, we're ready to continue writing our
application.
## Retrieving Pastes
The final step is to create the `retrieve` route which, given an `<id>`, will
return the corresponding paste if it exists.
We'll proceed with a `retrieve` route which, given an `<id>`, will return the
corresponding paste if it exists or otherwise **404**. As we now know, that
means we'll be reading the contents of the file corresponding to `<id>` in the
`upload/` directory and return them to the user.
Here's a first take at implementing the `retrieve` route. The route below takes
in an `<id>` as a dynamic path element. The handler uses the `id` to construct a
@ -321,11 +256,13 @@ paste doesn't exist.
```rust
# #[macro_use] extern crate rocket;
use std::path::Path;
use rocket::tokio::fs::File;
#[get("/<id>")]
async fn retrieve(id: &str) -> Option<File> {
let filename = format!("upload/{id}", id = id);
let upload_dir = concat!(env!("CARGO_MANIFEST_DIR"), "/", "upload");
let filename = Path::new(upload_dir).join(id);
File::open(&filename).await.ok()
}
```
@ -336,17 +273,22 @@ Make sure that the route is mounted at the root path:
# #[macro_use] extern crate rocket;
# #[get("/")] fn index() {}
# #[post("/")] fn upload() {}
# #[get("/<id>")] fn retrieve(id: String) {}
#[launch]
fn rocket() -> _ {
rocket::build().mount("/", routes![index, upload, retrieve])
rocket::build().mount("/", routes![index, retrieve])
}
```
Give it a try! Create some fake pastes in the `upload/` directory, run the
application, and try to retrieve them by visiting the corresponding URL.
### A Problem
Unfortunately, there's a problem with this code. Can you spot the issue? The
`&str` type should tip you off!
`&str` type in `retrieve` should tip you off! We've crafted a wonderful type to
represent paste IDs but have ignored it!
The issue is that the _user_ controls the value of `id`, and as a result, can
coerce the service into opening files inside `upload/` that aren't meant to be
@ -358,20 +300,27 @@ This is a big problem; it's known as the [full path disclosure
attack](https://www.owasp.org/index.php/Full_Path_Disclosure), and Rocket
provides the tools to prevent this and other kinds of attacks from happening.
To prevent the attack, we need to _validate_ `id` before we use it. Since the
`id` is a dynamic parameter, we can use Rocket's
[FromParam](@api/rocket/request/trait.FromParam.html) trait to
implement the validation and ensure that the `id` is a valid `PasteId` before
using it. We do this by implementing `FromParam` for `PasteId` in
`src/paste_id.rs`, as below:
### The Solution
To prevent the attack, we need to _validate_ `id` before we use it. We do so by
using a type more specific than `&str` to represent IDs and then asking Rocket
to validate the untrusted `id` input as that type. If validation fails, Rocket
will take care to not call our routes with bad input.
Typed validation for dynamic paramters like `id` is implemented via the
[`FromParam`] trait. Rocket uses `FromParam` to automatically validate and parse
dynamic path parameters like `id`. We already have a type that represents valid
paste IDs, `PasteId`, so we'll simply need to implement `FromParam` for
`PasteId`.
Here's the `FromParam` implementation for `PasteId` in `src/paste_id.rs`:
[`FromParam`]: @api/rocket/request/trait.FromParam.html
```rust
use std::borrow::Cow;
use rocket::request::FromParam;
/// A _probably_ unique paste ID.
pub struct PasteId<'a>(Cow<'a, str>);
# use std::borrow::Cow;
# pub struct PasteId<'a>(Cow<'a, str>);
/// Returns an instance of `PasteId` if the path segment is a valid ID.
/// Otherwise returns the invalid ID as the `Err` value.
@ -379,36 +328,48 @@ impl<'a> FromParam<'a> for PasteId<'a> {
type Error = &'a str;
fn from_param(param: &'a str) -> Result<Self, Self::Error> {
match param.chars().all(|c| c.is_ascii_alphanumeric()) {
true => Ok(PasteId(param.into())),
false => Err(param)
}
param.chars().all(|c| c.is_ascii_alphanumeric())
.then(|| PasteId(param.into()))
.ok_or(param)
}
}
```
Then, we simply need to change the type of `id` in the handler to `PasteId`.
Rocket will then ensure that `<id>` represents a valid `PasteId` before calling
the `retrieve` route, preventing attacks on the `retrieve` route:
! note: This implementation, while secure, could be improved.
Our `from_param` function is simplistic and could be improved by, for example,
checking that the length of the `id` is within some known bound, introducing
stricter character checks, checking for the existing of a paste file, and/or
potentially blacklisting sensitive files as needed.
Given this implementation, we can change the type of `id` in `retrieve` to
`PasteId`. Rocket will then ensure that `<id>` represents a valid `PasteId`
before calling the `retrieve` route, preventing the previous attack entirely:
```rust
# #[macro_use] extern crate rocket;
use rocket::tokio::fs::File;
# use std::borrow::Cow;
# use rocket::tokio::fs::File;
# type PasteId<'a> = &'a str;
# use std::path::PathBuf;
# use rocket::request::FromParam;
# pub struct PasteId<'a>(Cow<'a, str>);
# impl PasteId<'_> {
# pub fn new(size: usize) -> PasteId<'static> { todo!() }
# pub fn file_path(&self) -> PathBuf { todo!() }
# }
# impl<'a> FromParam<'a> for PasteId<'a> {
# type Error = &'a str;
# fn from_param(param: &'a str) -> Result<Self, Self::Error> { todo!() }
# }
#[get("/<id>")]
async fn retrieve(id: PasteId<'_>) -> Option<File> {
let filename = format!("upload/{id}", id = id);
File::open(&filename).await.ok()
File::open(id.file_path()).await.ok()
}
```
Note that our `from_param` function is simplistic and could be improved by, for
example, checking that the length of the `id` is within some known bound or
potentially blacklisting sensitive files as needed.
Notice how much nicer this implementation is! And this time, it's secure.
The wonderful thing about using `FromParam` and other Rocket traits is that they
centralize policies. For instance, here, we've centralized the policy for valid
@ -416,6 +377,140 @@ centralize policies. For instance, here, we've centralized the policy for valid
are added that require a `PasteId`, no further work has to be done: simply use
the type in the signature and Rocket takes care of the rest.
## Uploading
Now that we can retrieve pastes safely, it's time to actually store them. We'll
write an `upload` route that, according to our design, takes a paste's contents
and writes them to a file with a randomly generated ID inside of the `upload/`
directory. It'll return a URL to the client for the paste corresponding to the
`retrieve` route we just route.
### Streaming Data
To stream the incoming paste data to a file, we'll make use of [`Data`], a [data
guard] that represents an unopened stream to the incoming request body data.
Before we show you the code, you should attempt to write the route yourself.
Here's a hint: one possible route and handler signature look like this:
```rust
# #[macro_use] extern crate rocket;
use rocket::Data;
#[post("/", data = "<paste>")]
async fn upload(paste: Data<'_>) -> std::io::Result<String> {
/* .. */
# Ok("".into())
}
```
[`Data`]: @api/rocket/data/struct.Data.html
[data guard]: ../requests/#body-data
Your code should:
1. Create a new `PasteId` of a length of your choosing.
2. Construct a path to the `PasteId` inside of `upload/`.
3. Stream the `Data` to the file at the constructed path.
4. Construct a URL for the `PasteId`.
5. Return the URL to the client.
### Solution
Here's our version:
```rust
# #[macro_use] extern crate rocket;
// We derive `UriDisplayPath` for `PasteId` in `paste_id.rs`:
# use std::borrow::Cow;
# use std::path::{Path, PathBuf};
# use rocket::request::FromParam;
#[derive(UriDisplayPath)]
pub struct PasteId<'a>(Cow<'a, str>);
# impl PasteId<'_> {
# pub fn new(size: usize) -> PasteId<'static> { todo!() }
# pub fn file_path(&self) -> PathBuf { todo!() }
# }
#
# impl<'a> FromParam<'a> for PasteId<'a> {
# type Error = &'a str;
# fn from_param(param: &'a str) -> Result<Self, Self::Error> { todo!() }
# }
// We implement the `upload` route in `main.rs`:
use rocket::data::{Data, ToByteUnit};
use rocket::http::uri::Absolute;
# use rocket::tokio::fs::File;
// In a real application, these would be retrieved dynamically from a config.
const ID_LENGTH: usize = 3;
const HOST: Absolute<'static> = uri!("http://localhost:8000");
# #[get("/")] fn index() -> &'static str { "" }
# #[get("/<id>")] fn retrieve(id: PasteId<'_>) -> Option<File> { todo!() }
#[post("/", data = "<paste>")]
async fn upload(paste: Data<'_>) -> std::io::Result<String> {
let id = PasteId::new(ID_LENGTH);
paste.open(128.kibibytes()).into_file(id.file_path()).await?;
Ok(uri!(HOST, retrieve(id)).to_string())
}
```
We note the following Rocket APIs being used in our implementation:
* The [`kibibytes()`] method, which comes from the [`ToByteUnit`] trait.
* [`Data::open()`] to open [`Data`] as a [`DataStream`].
* [`DataStream::into_file()`] for writing the data stream into a file.
* The [`UriDisplayPath`] derive, allowing `PasteId` to be used in [`uri!`].
* The [`uri!`] macro to crate type-safe, URL-safe URIs.
[`Data::open()`]: @api/rocket/data/struct.Data.html#method.open
[`Data`]: @api/rocket/data/struct.Data.html
[`DataStream`]: @api/rocket/data/struct.DataStream.html
[`DataStream::into_file()`]: @api/rocket/data/struct.DataStream.html#method.into_file
[`uri!`]: @api/rocket/macro.uri.html
[`kibibytes()`]: @api/rocket/data/trait.ToByteUnit.html#tymethod.kibibytes
[`ToByteUnit`]: @api/rocket/data/trait.ToByteUnit.html
[`UriDisplayPath`]: @api/rocket/derive.UriDisplayPath.html
Ensure that the route is mounted at the root path:
```rust
# #[macro_use] extern crate rocket;
# #[get("/")] fn index() {}
# #[get("/<id>")] fn retrieve(id: &str) {}
# #[post("/")] fn upload() {}
#[launch]
fn rocket() -> _ {
rocket::build().mount("/", routes![index, retrieve, upload])
}
```
Test that your route works via `cargo run`. From a separate terminal, upload a
file using `curl` then retrieve the paste using the returned URL.
```sh
## in the project root
cargo run
## in a separate terminal
echo "Hello, Rocket!" | curl --data-binary @- http://localhost:8000
## => http://localhost:8000/eGs
## confirm we can retrieve the paste (replace with URL from above)
curl http://localhost:8000/eGs
## we can check the contents of `upload/` as well
<ctrl-c> # kill running process
ls upload # ensure the upload is there
cat upload/* # ensure that contents are correct
```
## Conclusion
That's it! Ensure that all of your routes are mounted and test your application.

View File

@ -28,8 +28,8 @@ aspect of Rocket. The sections are:
- **[Testing](testing/):** how to unit and integration test a Rocket
application.
- **[Configuration](configuration/):** how to configure a Rocket application.
- **[Pastebin](pastebin/):** a tutorial on how to create a pastebin with
Rocket.
- **[Pastebin Tutorial](pastebin/):** a tutorial on how to create a pastebin
with Rocket.
- **[Conclusion](conclusion/):** concludes the guide and discusses next steps
for learning.
- **[FAQ](faq/):** answers to frequently asked questions about Rocket and