Struct mime_4::MediaType

pub struct MediaType { /* fields omitted */ }

A parsed media type (or "MIME").

Getting a MediaType

There are several constants exported for common media types:

let text = mime::TEXT_PLAIN;
let svg = mime::IMAGE_SVG;
let json = mime::APPLICATION_JSON;
// etc

A MediaType can also be parsed from a string, such as from a Content-Type HTTP header:

match mime::MediaType::parse("text/plain; charset=utf-8") {
    Ok(text) => assert_eq!(text, mime::TEXT_PLAIN_UTF_8),
    Err(err) => panic!("you should handle this parse error: {}", err),
}

Inspecting MediaTypes

Once you have a MediaType, you can inspect the various parts of it. Since the type_() and subtype() methods return &str, you can make easy-to-read match statements to handle different media types. To prevent typos, many common type names are available as constants.

let mime = mime::TEXT_PLAIN;
match (mime.type_(), mime.subtype()) {
    (mime::TEXT, mime::PLAIN) => println!("plain text!"),
    (mime::TEXT, _) => println!("structured text"),
    _ => println!("not text"),
}

Note about wildcards (*)

A MediaType represents an exact format type. The HTTP Accept header can include "media ranges", which can match multiple media types. Those "media ranges" should be represented as MediaRange.

Implementations

impl MediaType

pub fn parse(source: impl Parse) -> Result<Self, InvalidMime>

Parse a string as a MediaType.

Example

let mt = mime::MediaType::parse("text/plain").unwrap();
assert_eq!(mt, mime::TEXT_PLAIN);

Errors

Returns an error if the source is not a valid media type.

pub fn type_(&self) -> &str

Get the top level media type for this MediaType.

Example

let mime = mime::TEXT_PLAIN;
assert_eq!(mime.type_(), "text");
assert_eq!(mime.type_(), mime::TEXT);

pub fn subtype(&self) -> &str

Get the subtype of this MediaType.

Example

let mime = mime::TEXT_PLAIN;
assert_eq!(mime.subtype(), "plain");
assert_eq!(mime.subtype(), mime::PLAIN);

let svg = mime::IMAGE_SVG;
assert_eq!(svg.subtype(), mime::SVG);
assert_eq!(svg.subtype(), "svg+xml");

pub fn suffix(&self) -> Option<&str>

Get an optional +suffix for this MediaType.

Example

let svg = mime::IMAGE_SVG;
assert_eq!(svg.suffix(), Some(mime::XML));
assert_eq!(svg.suffix(), Some("xml"));


assert!(mime::TEXT_PLAIN.suffix().is_none());

pub fn param<'a>(&'a self, attr: &str) -> Option<Value<'a>>

Look up a parameter by name.

Example

let mime = mime::TEXT_PLAIN_UTF_8;
assert_eq!(mime.param(mime::CHARSET), Some(mime::UTF_8));
assert_eq!(mime.param("charset").unwrap(), "utf-8");
assert!(mime.param("boundary").is_none());

let mime = "multipart/form-data; boundary=ABCDEFG".parse::<mime::MediaType>().unwrap();
assert_eq!(mime.param(mime::BOUNDARY).unwrap(), "ABCDEFG");

pub fn params(&self) -> impl Iterator<Item = (&str, Value<'_>)>

Returns an iterator over the parameters.

Example

let pkcs7 = mime::MediaType::parse(
    "application/pkcs7-mime; smime-type=enveloped-data; name=smime.p7m"
).unwrap();

let mut params = pkcs7.params();

let (name, value) = params.next().unwrap();
assert_eq!(name, "smime-type");
assert_eq!(value, "enveloped-data");

let (name, value) = params.next().unwrap();
assert_eq!(name, "name");
assert_eq!(value, "smime.p7m");

assert!(params.next().is_none());

pub fn has_params(&self) -> bool

Returns true if the media type has at last one parameter.

Example

let plain_text: mime::MediaType = "text/plain".parse().unwrap();
assert_eq!(plain_text.has_params(), false);

let plain_text_utf8: mime::MediaType = "text/plain; charset=utf-8".parse().unwrap();
assert_eq!(plain_text_utf8.has_params(), true);

pub fn without_params(mut self: Self) -> Self

Transforms the media type into its non-parametrized form.

Example

use mime::MediaType;

let html_xml_utf8 = MediaType::parse("text/html+xml; charset=utf-8").unwrap();
assert!(html_xml_utf8.has_params());

let html_xml = html_xml_utf8.without_params();
assert!(!html_xml.has_params());

assert_eq!(html_xml, "text/html+xml");

Trait Implementations

impl AsRef<str> for MediaType

fn as_ref(&self) -> &str

Performs the conversion.

impl Clone for MediaType

fn clone(&self) -> MediaType

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for MediaType

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

Formats the value using the given formatter.

impl Display for MediaType

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

Formats the value using the given formatter.

impl From<MediaType> for MediaRange

Any MediaType can freely be a MediaRange.

Example

// If we only supported `text/plain`:
let range = mime::MediaRange::from(mime::TEXT_PLAIN);

fn from(mt: MediaType) -> MediaRange

Performs the conversion.

impl FromStr for MediaType

type Err = InvalidMime

The associated error which can be returned from parsing.

fn from_str(s: &str) -> Result<MediaType, Self::Err>

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

impl<'a> PartialEq<&'a str> for MediaType

fn eq(&self, s: &&'a str) -> bool

This method tests for self and other values to be equal, and is used by ==.

#[must_use]pub fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl PartialEq<MediaType> for MediaType

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

This method tests for self and other values to be equal, and is used by ==.

#[must_use]pub fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl PartialEq<str> for MediaType

fn eq(&self, s: &str) -> bool

This method tests for self and other values to be equal, and is used by ==.

#[must_use]pub fn ne(&self, other: &Rhs) -> bool

This method tests for !=.