Struct Accept

pub struct Accept(/* private fields */);

The HTTP Accept header.

An Accept header is composed of zero or more media types, each of which may have an optional quality value (a QMediaType). The header is sent by an HTTP client to describe the formats it accepts as well as the order in which it prefers different formats.

Usage

The Accept header of an incoming request can be retrieved via the Request::accept() method. The preferred() method can be used to retrieve the client’s preferred media type.

An Accept type with a single, common media type can be easily constructed via provided associated constants.

Example

Construct an Accept header with a single application/json media type:

use rocket::http::Accept;

let accept_json = Accept::JSON;

Header

Accept implements Into<Header>. As such, it can be used in any context where an Into<Header> is expected:

use rocket::http::Accept;
use rocket::response::Response;

let response = Response::build().header(Accept::JSON).finalize();

Implementations

impl Accept

pub const Any: Accept

An Accept header with the single media type for any media type: /

pub const Binary: Accept

An Accept header with the single media type for binary data: application/octet-stream

pub const Bytes: Accept

An Accept header with the single media type for binary data: application/octet-stream

pub const HTML: Accept

An Accept header with the single media type for HTML: text/html

pub const Plain: Accept

An Accept header with the single media type for plain text: text/plain

pub const Text: Accept

An Accept header with the single media type for plain text: text/plain

pub const JSON: Accept

An Accept header with the single media type for JSON: application/json

pub const MsgPack: Accept

An Accept header with the single media type for MsgPack: application/msgpack

pub const Form: Accept

An Accept header with the single media type for forms: application/x-www-form-urlencoded

pub const JavaScript: Accept

An Accept header with the single media type for JavaScript: text/javascript

pub const CSS: Accept

An Accept header with the single media type for CSS: text/css

pub const FormData: Accept

An Accept header with the single media type for multipart form data: multipart/form-data

pub const XML: Accept

An Accept header with the single media type for XML: text/xml

pub const OPF: Accept

An Accept header with the single media type for OPF: application/oebps-package+xml

pub const XHTML: Accept

An Accept header with the single media type for XHTML: application/xhtml+xml

pub const CSV: Accept

An Accept header with the single media type for CSV: text/csv

pub const PNG: Accept

An Accept header with the single media type for PNG: image/png

pub const GIF: Accept

An Accept header with the single media type for GIF: image/gif

pub const BMP: Accept

An Accept header with the single media type for BMP: image/bmp

pub const JPEG: Accept

An Accept header with the single media type for JPEG: image/jpeg

pub const WEBP: Accept

An Accept header with the single media type for WEBP: image/webp

pub const AVIF: Accept

An Accept header with the single media type for AVIF: image/avif

pub const SVG: Accept

An Accept header with the single media type for SVG: image/svg+xml

pub const Icon: Accept

An Accept header with the single media type for Icon: image/x-icon

pub const WEBM: Accept

An Accept header with the single media type for WEBM: video/webm

pub const WEBA: Accept

An Accept header with the single media type for WEBM Audio: audio/webm

pub const OGG: Accept

An Accept header with the single media type for OGG Video: video/ogg

pub const FLAC: Accept

An Accept header with the single media type for FLAC: audio/flac

pub const WAV: Accept

An Accept header with the single media type for WAV: audio/wav

pub const PDF: Accept

An Accept header with the single media type for PDF: application/pdf

pub const TTF: Accept

An Accept header with the single media type for TTF: application/font-sfnt

pub const OTF: Accept

An Accept header with the single media type for OTF: application/font-sfnt

pub const WOFF: Accept

An Accept header with the single media type for WOFF: application/font-woff

pub const WOFF2: Accept

An Accept header with the single media type for WOFF2: font/woff2

pub const JsonApi: Accept

An Accept header with the single media type for JSON API: application/vnd.api+json

pub const WASM: Accept

An Accept header with the single media type for WASM: application/wasm

pub const TIFF: Accept

An Accept header with the single media type for TIFF: image/tiff

pub const AAC: Accept

An Accept header with the single media type for AAC Audio: audio/aac

pub const Calendar: Accept

An Accept header with the single media type for iCalendar: text/calendar

pub const MPEG: Accept

An Accept header with the single media type for MPEG Video: video/mpeg

pub const TAR: Accept

An Accept header with the single media type for tape archive: application/x-tar

pub const GZIP: Accept

An Accept header with the single media type for gzipped binary: application/gzip

pub const MOV: Accept

An Accept header with the single media type for quicktime video: video/quicktime

pub const MP3: Accept

An Accept header with the single media type for MPEG Audio: audio/mpeg

pub const MP4: Accept

An Accept header with the single media type for MPEG4 Video: video/mp4

pub const ZIP: Accept

An Accept header with the single media type for ZIP archive: application/zip

pub const CBZ: Accept

An Accept header with the single media type for Comic ZIP archive: application/vnd.comicbook+zip

pub const CBR: Accept

An Accept header with the single media type for Comic RAR compressed archive: application/vnd.comicbook-rar

pub const RAR: Accept

An Accept header with the single media type for RAR compressed archive: application/vnd.rar

pub const EPUB: Accept

An Accept header with the single media type for EPUB: application/epub+zip

pub const EventStream: Accept

An Accept header with the single media type for SSE stream: text/event-stream

pub const Markdown: Accept

An Accept header with the single media type for markdown text: text/markdown

pub const EXE: Accept

An Accept header with the single media type for executable: application/vnd.microsoft.portable-executable

pub fn new<T, M>(items: T) -> Accept

where T: IntoIterator<Item = M>, M: Into<QMediaType>,

Constructs a new Accept header from one or more media types.

The items parameter may be of type QMediaType, [QMediaType], &[QMediaType] or Vec<QMediaType>. To prevent additional allocations, prefer to provide inputs of type QMediaType, [QMediaType], or Vec<QMediaType>.

Example

use rocket::http::{QMediaType, MediaType, Accept};

// Construct an `Accept` via a `Vec<MediaType>`.
let json_then_html = vec![MediaType::JSON, MediaType::HTML];
let accept = Accept::new(json_then_html);
assert_eq!(accept.preferred().media_type(), &MediaType::JSON);

// Construct an `Accept` via an `[MediaType]`.
let accept = Accept::new([MediaType::JSON, MediaType::HTML]);
assert_eq!(accept.preferred().media_type(), &MediaType::JSON);

// Construct an `Accept` via a single `QMediaType`.
let accept = Accept::new(QMediaType(MediaType::JSON, Some(0.4)));
assert_eq!(accept.preferred().media_type(), &MediaType::JSON);

pub fn add<M>(&mut self, media_type: M)

where M: Into<QMediaType>,

Adds media_type to self.

Example

use rocket::http::{QMediaType, MediaType, Accept};

let mut accept = Accept::new(QMediaType(MediaType::JSON, Some(0.1)));
assert_eq!(accept.preferred().media_type(), &MediaType::JSON);
assert_eq!(accept.iter().count(), 1);

accept.add(QMediaType(MediaType::HTML, Some(0.7)));
assert_eq!(accept.preferred().media_type(), &MediaType::HTML);
assert_eq!(accept.iter().count(), 2);

accept.add(QMediaType(MediaType::XML, Some(0.6)));
assert_eq!(accept.preferred().media_type(), &MediaType::HTML);
assert_eq!(accept.iter().count(), 3);

pub fn preferred(&self) -> &QMediaType

Retrieve the client’s preferred media type. This method follows RFC 7231 5.3.2. If the list of media types is empty, this method returns a media type of any with no quality value: (*/*).

Example

use rocket::http::{QMediaType, MediaType, Accept};

let media_types = vec![
    QMediaType(MediaType::JSON, Some(0.3)),
    QMediaType(MediaType::HTML, Some(0.9))
];

let accept = Accept::new(media_types);
assert_eq!(accept.preferred().media_type(), &MediaType::HTML);

pub fn first(&self) -> Option<&QMediaType>

Retrieve the first media type in self, if any.

Example

use rocket::http::{QMediaType, MediaType, Accept};

let accept = Accept::new(QMediaType(MediaType::XML, None));
assert_eq!(accept.first(), Some(&MediaType::XML.into()));

pub fn iter(&self) -> impl Iterator<Item = &QMediaType>

Returns an iterator over all of the (quality) media types in self. Media types are returned in the order in which they appear in the header.

Example

use rocket::http::{QMediaType, MediaType, Accept};

let qmedia_types = vec![
    QMediaType(MediaType::JSON, Some(0.3)),
    QMediaType(MediaType::HTML, Some(0.9))
];

let accept = Accept::new(qmedia_types.clone());

let mut iter = accept.iter();
assert_eq!(iter.next(), Some(&qmedia_types[0]));
assert_eq!(iter.next(), Some(&qmedia_types[1]));
assert_eq!(iter.next(), None);

pub fn media_types(&self) -> impl Iterator<Item = &MediaType>

Returns an iterator over all of the (bare) media types in self. Media types are returned in the order in which they appear in the header.

Example

use rocket::http::{QMediaType, MediaType, Accept};

let qmedia_types = vec![
    QMediaType(MediaType::JSON, Some(0.3)),
    QMediaType(MediaType::HTML, Some(0.9))
];

let accept = Accept::new(qmedia_types.clone());

let mut iter = accept.media_types();
assert_eq!(iter.next(), Some(qmedia_types[0].media_type()));
assert_eq!(iter.next(), Some(qmedia_types[1].media_type()));
assert_eq!(iter.next(), None);

Trait Implementations

impl Clone for Accept

fn clone(&self) -> Accept

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Accept

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Display for Accept

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl From<Accept> for Header<'static>

Creates a new Header with name Accept and the value set to the HTTP rendering of this Accept header.

fn from(val: Accept) -> Header<'static>

Converts to this type from the input type.

impl<T> From<T> for Accept

where T: IntoIterator<Item = MediaType>,

fn from(items: T) -> Accept

Converts to this type from the input type.

impl<'r> FromRequest<'r> for &'r Accept

type Error = Infallible

The associated error to be returned if derivation fails.

fn from_request<'life0, 'async_trait>( request: &'r Request<'life0>, ) -> Pin<Box<dyn Future<Output = Outcome<Self, Infallible>> + Send + 'async_trait>>

where Self: 'async_trait, 'r: 'async_trait, 'life0: 'async_trait,

Derives an instance of Self from the incoming request metadata.

impl FromStr for Accept

type Err = String

The associated error which can be returned from parsing.

fn from_str(raw: &str) -> Result<Accept, String>

Parses a string s to return a value of this type.

impl PartialEq for Accept

fn eq(&self, other: &Accept) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.