use response;
use handler::ErrorHandler;
use codegen::StaticCatchInfo;
use error::Error;
use request::Request;
use std::fmt;
use term_painter::ToStyle;
use term_painter::Color::*;
/// An error catching route.
///
/// Catchers are routes that run when errors occur. They correspond directly
/// with the HTTP error status code they will be handling and are registered
/// with Rocket via the [Rocket::catch](/rocket/struct.Rocket.html#method.catch)
/// method. For example, to handle "404 not found" errors, a catcher for the
/// "404" status code is registered.
///
/// Because error handlers are only called when all routes are exhausted, they
/// should not fail nor forward. If an error catcher fails, the user will
/// receive no response. If an error catcher forwards, Rocket will respond with
/// an internal server error.
///
/// # Built-In Catchers
///
/// Rocket has many built-in, pre-registered default catchers. In particular,
/// Rocket has catchers for all of the following status codes: 400, 401, 402,
/// 403, 404, 405, 406, 407, 408, 409, 410, 411, 412, 413, 414, 415, 416, 417,
/// 418, 421, 426, 428, 429, 431, 451, 500, 501, 503, and 510. As such, catchers
/// only need to be registered if an error needs to be handled in a custom
/// fashion.
///
/// # Code Generation
///
/// Catchers should rarely be used directly. Instead, they are typically
/// declared using the `error` decorator, as follows:
///
/// ```rust
/// #![feature(plugin)]
/// #![plugin(rocket_codegen)]
///
/// extern crate rocket;
///
/// use rocket::Request;
///
/// #[error(500)]
/// fn internal_error() -> &'static str {
/// "Whoops! Looks like we messed up."
/// }
///
/// #[error(400)]
/// fn not_found(req: &Request) -> String {
/// format!("I couldn't find '{}'. Try something else?", req.uri())
/// }
///
/// fn main() {
/// # if false { // We don't actually want to launch the server in an example.
/// rocket::ignite().catch(errors![internal_error, not_found]).launch()
/// # }
/// }
/// ```
///
/// A function decorated with `error` can take in 0, 1, or 2 parameters:
/// `Error`, `&Request`, or both, as desired.
pub struct Catcher {
/// The HTTP status code to match against.
pub code: u16,
handler: ErrorHandler,
is_default: bool,
}
impl Catcher {
/// Creates a catcher for the given status code using the given error
/// handler. This should only be used when routing manually.
///
/// # Examples
///
/// ```rust
/// use rocket::{Catcher, Request, Error};
/// use rocket::response::{Result, Responder};
///
/// fn handle_404<'r>(_: Error, req: &'r Request) -> Result<'r> {
/// format!("Couldn't find: {}", req.uri()).respond()
/// }
///
/// fn handle_500<'r>(_: Error, _: &'r Request) -> Result<'r> {
/// "Whoops, we messed up!".respond()
/// }
///
/// let not_found_catcher = Catcher::new(404, handle_404);
/// let internal_server_error_catcher = Catcher::new(500, handle_500);
/// ```
#[inline(always)]
pub fn new(code: u16, handler: ErrorHandler) -> Catcher {
Catcher { code: code, handler: handler, is_default: false }
}
#[doc(hidden)]
#[inline(always)]
pub fn handle<'r>(&self, err: Error, req: &'r Request) -> response::Result<'r> {
(self.handler)(err, req)
}
#[inline(always)]
fn new_default(code: u16, handler: ErrorHandler) -> Catcher {
Catcher { code: code, handler: handler, is_default: true, }
}
#[doc(hidden)]
#[inline(always)]
pub fn is_default(&self) -> bool {
self.is_default
}
}
#[doc(hidden)]
impl<'a> From<&'a StaticCatchInfo> for Catcher {
fn from(info: &'a StaticCatchInfo) -> Catcher {
Catcher::new(info.code, info.handler)
}
}
impl fmt::Display for Catcher {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "{}", Blue.paint(&self.code))
}
}
macro_rules! error_page_template {
($code:expr, $name:expr, $description:expr) => (
concat!(r#"
"#, $code, " ", $name, r#"
"#, $code, ": ", $name, r#"
"#, $description, r#"
Rocket
"#
)
)
}
macro_rules! default_errors {
($($code:expr, $name:expr, $description:expr, $fn_name:ident),+) => (
let mut map = HashMap::new();
$(
fn $fn_name<'r>(_: Error, _r: &'r Request) -> response::Result<'r> {
status::Custom(Status::from_code($code).unwrap(),
content::HTML(error_page_template!($code, $name, $description))
).respond()
}
map.insert($code, Catcher::new_default($code, $fn_name));
)+
map
)
}
pub mod defaults {
use super::Catcher;
use std::collections::HashMap;
use request::Request;
use response::{self, content, status, Responder};
use http::Status;
use error::Error;
pub fn get() -> HashMap {
default_errors! {
400, "Bad Request", "The request could not be understood by the server due
to malformed syntax.", handle_400,
401, "Unauthorized", "The request requires user authentication.",
handle_401,
402, "Payment Required", "The request could not be processed due to lack of
payment.", handle_402,
403, "Forbidden", "The request was forbidden by the server.
Check authentication.", handle_403,
404, "Not Found", "The requested resource could not be found.", handle_404,
405, "Method Not Allowed", "The request method is not supported for the
requested resource.", handle_405,
406, "Not Acceptable", "The requested resource is capable of generating
only content not acceptable according to the Accept headers sent in the
request.", handle_406,
407, "Proxy Authentication Required", "Authentication with the proxy is
required.", handle_407,
408, "Request Timeout", "The server timed out waiting for the
request.", handle_408,
409, "Conflict", "The request could not be processed because of a conflict
in the request.", handle_409,
410, "Gone", "The resource requested is no longer available and will not be
available again.", handle_410,
411, "Length Required", "The request did not specify the length of its
content, which is required by the requested resource.", handle_411,
412, "Precondition Failed", "The server does not meet one of the
preconditions specified in the request.", handle_412,
413, "Payload Too Large", "The request is larger than the server is
willing or able to process.", handle_413,
414, "URI Too Long", "The URI provided was too long for the server to
process.", handle_414,
415, "Unsupported Media Type", "The request entity has a media type which
the server or resource does not support.", handle_415,
416, "Range Not Satisfiable", "The portion of the requested file cannot be
supplied by the server.", handle_416,
417, "Expectation Failed", "The server cannot meet the requirements of the
Expect request-header field.", handle_417,
418, "I'm a teapot", "I was requested to brew coffee, and I am a
teapot.", handle_418,
421, "Misdirected Request", "The server cannot produce a response for this
request.", handle_421,
426, "Upgrade Required", "Switching to the protocol in the Upgrade header
field is required.", handle_426,
428, "Precondition Required", "The server requires the request to be
conditional.", handle_428,
429, "Too Many Requests", "Too many requests have been received
recently.", handle_429,
431, "Request Header Fields Too Large", "The server is unwilling to process
the request because either an individual header field, or all
the header fields collectively, are too large.", handle_431,
451, "Unavailable For Legal Reasons", "The requested resource is
unavailable due to a legal demand to deny access to this
resource.", handle_451,
500, "Internal Server Error", "The server encountered an internal error
while processing this request.", handle_500,
501, "Not Implemented", "The server either does not recognize the request
method, or it lacks the ability to fulfill the request.", handle_501,
503, "Service Unavailable", "The server is currently unavailable.",
handle_503,
510, "Not Extended", "Further extensions to the request are required for
the server to fulfill it.", handle_510
}
}
}