Struct reqwest::header::Headers

pub struct Headers { /* fields omitted */ }

A map of header fields on requests and responses.

Methods

impl Headers

pub fn new() -> Headers

Creates a new, empty headers map.

pub fn with_capacity(len: usize) -> Headers

Creates a new Headers struct with space reserved for len headers.

pub fn set<H>(&mut self, value: H) where
    H: Header, 

Set a header field to the corresponding value.

The field is determined by the type of the value being set.

pub fn get<H>(&self) -> Option<&H> where
    H: Header, 

Get a reference to the header field's value, if it exists.

pub fn get_mut<H>(&mut self) -> Option<&mut H> where
    H: Header, 

Get a mutable reference to the header field's value, if it exists.

pub fn has<H>(&self) -> bool where
    H: Header, 

Returns a boolean of whether a certain header is in the map.

Example:

headers.set(ContentType::json());
assert!(headers.has::<ContentType>());

pub fn remove<H>(&mut self) -> Option<H> where
    H: Header, 

Removes a header from the map, if one existed. Returns the header, if one has been removed and could be parsed.

Note that this function may return None even though a header was removed. If you want to know whether a header exists, rather rely on has.

Important traits for HeadersItems<'a>

impl<'a> Iterator for HeadersItems<'a> type Item = HeaderView<'a>;

pub fn iter(&self) -> HeadersItems

Returns an iterator over the header fields.

pub fn len(&self) -> usize

Returns the number of headers in the map.

pub fn clear(&mut self)

Remove all headers from the map.

pub fn get_raw(&self, name: &str) -> Option<&Raw>

Access the raw value of a header.

Prefer to use the typed getters instead.

Example:

let raw = headers.get_raw("content-type").unwrap();
assert_eq!(raw, "text/plain");

pub fn set_raw<K, V>(&mut self, name: K, value: V) where
    K: Into<Cow<'static, str>>,
    V: Into<Raw>, 

Set the raw value of a header, bypassing any typed headers.

Example:

headers.set_raw("content-length", b"1".as_ref());
headers.set_raw("content-length", "2");
headers.set_raw("content-length", "3".to_string());
headers.set_raw("content-length", vec![vec![b'4']]);

pub fn append_raw<K, V>(&mut self, name: K, value: V) where
    K: Into<Cow<'static, str>>,
    V: Into<Raw>, 

Append a value to raw value of this header.

If a header already contains a value, this will add another line to it.

If a header does not exist for this name, a new one will be created with the value.

Example:

headers.append_raw("x-foo", b"bar".to_vec());
headers.append_raw("x-foo", b"quux".to_vec());

pub fn remove_raw(&mut self, name: &str)

Remove a header by name.

Trait Implementations

impl<'a> FromIterator<HeaderView<'a>> for Headers

fn from_iter<I>(iter: I) -> Headers where
    I: IntoIterator<Item = HeaderView<'a>>, 

Creates a value from an iterator.

impl Default for Headers

fn default() -> Headers

Returns the "default value" for a type.

impl Display for Headers

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

Formats the value using the given formatter.

impl PartialEq<Headers> for Headers

fn eq(&self, other: &Headers) -> 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 !=.

impl<'a> Extend<HeaderView<'a>> for Headers

fn extend<I>(&mut self, iter: I) where
    I: IntoIterator<Item = HeaderView<'a>>, 

Extends a collection with the contents of an iterator.

impl<'a> Extend<(&'a str, Bytes)> for Headers

fn extend<I>(&mut self, iter: I) where
    I: IntoIterator<Item = (&'a str, Bytes)>, 

Extends a collection with the contents of an iterator.

impl Debug for Headers

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

Formats the value using the given formatter.

impl Clone for Headers

fn clone(&self) -> Headers

Returns a copy of the value.

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

Performs copy-assignment from source.