Struct mime_guess::MimeGuess

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

A “guess” of the MIME/Media Type(s) of an extension or path as one or more Mime instances.

Note: Ordering

A given file format may have one or more applicable Media Types; in this case the first Media Type returned is whatever is declared in the latest IETF RFC for the presumed file format or the one that explicitly supercedes all others. Ordering of additional Media Types is arbitrary.

Note: Values Not Stable

The exact Media Types returned in any given guess are not considered to be stable and are often updated in patch releases in order to reflect the most up-to-date information possible.

Implementations

impl MimeGuess

pub fn from_ext(ext: &str) -> MimeGuess

Guess the MIME type of a file (real or otherwise) with the given extension.

The search is case-insensitive.

If ext is empty or has no (currently) known MIME type mapping, then an empty guess is returned.

pub fn from_path<P: AsRef<Path>>(path: P) -> MimeGuess

Guess the MIME type of path by its extension (as defined by Path::extension()). No disk access is performed.

If path has no extension, the extension cannot be converted to str, or has no known MIME type mapping, then an empty guess is returned.

The search is case-insensitive.

Note

Guess is the operative word here, as there are no guarantees that the contents of the file that path points to match the MIME type associated with the path’s extension.

Take care when processing files with assumptions based on the return value of this function.

pub fn is_empty(&self) -> bool

true if the guess did not return any known mappings for the given path or extension.

pub fn count(&self) -> usize

Get the number of MIME types in the current guess.

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

Get the first guessed Mime, if applicable.

See Note: Ordering above.

pub fn first_raw(&self) -> Option<&'static str>

Get the first guessed Media Type as a string, if applicable.

See Note: Ordering above.

pub fn first_or_octet_stream(&self) -> Mime

Get the first guessed Mime, or if the guess is empty, return application/octet-stream instead.

See Note: Ordering above.

Note: HTTP Applications

For HTTP request and response bodies if a value for the Content-Type header cannot be determined it might be preferable to not send one at all instead of defaulting to application/octet-stream as the recipient will expect to infer the format directly from the content instead. (RFC 7231, Section 3.1.1.5)

On the contrary, for multipart/form-data bodies, the Content-Type of a form-data part is assumed to be text/plain unless specified so a default of application/octet-stream for non-text parts is safer. (RFC 7578, Section 4.4)

pub fn first_or_text_plain(&self) -> Mime

Get the first guessed Mime, or if the guess is empty, return text/plain instead.

See Note: Ordering above.

pub fn first_or(&self, default: Mime) -> Mime

Get the first guessed Mime, or if the guess is empty, return the given Mime instead.

See Note: Ordering above.

pub fn first_or_else<F>(&self, default_fn: F) -> Mime

where F: FnOnce() -> Mime,

Get the first guessed Mime, or if the guess is empty, execute the closure and return its result.

See Note: Ordering above.

pub fn iter(&self) -> Iter

Get an iterator over the Mime values contained in this guess.

See Note: Ordering above.

pub fn iter_raw(&self) -> IterRaw

Get an iterator over the raw media-type strings in this guess.

See Note: Ordering above.

Trait Implementations

impl Clone for MimeGuess

fn clone(&self) -> MimeGuess

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for MimeGuess

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

Formats the value using the given formatter.

impl<'a> IntoIterator for &'a MimeGuess

type Item = Mime

The type of the elements being iterated over.

type IntoIter = Iter

Which kind of iterator are we turning this into?

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

impl IntoIterator for MimeGuess

type Item = Mime

The type of the elements being iterated over.

type IntoIter = Iter

Which kind of iterator are we turning this into?

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

impl PartialEq for MimeGuess

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

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

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

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

impl Copy for MimeGuess

impl Eq for MimeGuess

impl StructuralPartialEq for MimeGuess