pub struct HeaderName { /* private fields */ }
Expand description
Represents an HTTP header field name
Header field names identify the header. Header sets may include multiple headers with the same name. The HTTP specification defines a number of standard headers, but HTTP messages may include non-standard header names as well as long as they adhere to the specification.
HeaderName
is used as the HeaderMap
key. Constants are available for
all standard header names in the header
module.
§Representation
HeaderName
represents standard header names using an enum
, as such they
will not require an allocation for storage. All custom header names are
lower cased upon conversion to a HeaderName
value. This avoids the
overhead of dynamically doing lower case conversion during the hash code
computation and the comparison operation.
Implementations§
Source§impl HeaderName
impl HeaderName
Sourcepub fn from_bytes(src: &[u8]) -> Result<HeaderName, InvalidHeaderName>
pub fn from_bytes(src: &[u8]) -> Result<HeaderName, InvalidHeaderName>
Converts a slice of bytes to an HTTP header name.
This function normalizes the input.
Sourcepub fn from_lowercase(src: &[u8]) -> Result<HeaderName, InvalidHeaderName>
pub fn from_lowercase(src: &[u8]) -> Result<HeaderName, InvalidHeaderName>
Converts a slice of bytes to an HTTP header name.
This function expects the input to only contain lowercase characters. This is useful when decoding HTTP/2.0 or HTTP/3.0 headers. Both require that all headers be represented in lower case.
§Examples
// Parsing a lower case header
let hdr = HeaderName::from_lowercase(b"content-length").unwrap();
assert_eq!(CONTENT_LENGTH, hdr);
// Parsing a header that contains uppercase characters
assert!(HeaderName::from_lowercase(b"Content-Length").is_err());
Sourcepub const fn from_static(src: &'static str) -> HeaderName
pub const fn from_static(src: &'static str) -> HeaderName
Converts a static string to a HTTP header name.
This function requires the static string to only contain lowercase characters, numerals and symbols, as per the HTTP/2.0 specification and header names internal representation within this library.
§Panics
This function panics when the static string is a invalid header.
Until Allow panicking in constants makes its way into stable, the panic message at compile-time is going to look cryptic, but should at least point at your header value:
error: any use of this value will cause an error
--> http/src/header/name.rs:1241:13
|
1241 | ([] as [u8; 0])[0]; // Invalid header name
| ^^^^^^^^^^^^^^^^^^
| |
| index out of bounds: the length is 0 but the index is 0
| inside `http::HeaderName::from_static` at http/src/header/name.rs:1241:13
| inside `INVALID_NAME` at src/main.rs:3:34
|
::: src/main.rs:3:1
|
3 | const INVALID_NAME: HeaderName = HeaderName::from_static("Capitalized");
| ------------------------------------------------------------------------
§Examples
// Parsing a standard header
let hdr = HeaderName::from_static("content-length");
assert_eq!(CONTENT_LENGTH, hdr);
// Parsing a custom header
let CUSTOM_HEADER: &'static str = "custom-header";
let a = HeaderName::from_lowercase(b"custom-header").unwrap();
let b = HeaderName::from_static(CUSTOM_HEADER);
assert_eq!(a, b);
// Parsing a header that contains invalid symbols(s):
HeaderName::from_static("content{}{}length"); // This line panics!
// Parsing a header that contains invalid uppercase characters.
let a = HeaderName::from_static("foobar");
let b = HeaderName::from_static("FOOBAR"); // This line panics!
Trait Implementations§
Source§impl AsRef<[u8]> for HeaderName
impl AsRef<[u8]> for HeaderName
Source§impl AsRef<str> for HeaderName
impl AsRef<str> for HeaderName
Source§impl Borrow<str> for HeaderName
impl Borrow<str> for HeaderName
Source§impl Clone for HeaderName
impl Clone for HeaderName
Source§fn clone(&self) -> HeaderName
fn clone(&self) -> HeaderName
1.0.0 · Source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moreSource§impl Debug for HeaderName
impl Debug for HeaderName
Source§impl Display for HeaderName
impl Display for HeaderName
Source§impl<'a> From<&'a HeaderName> for HeaderName
impl<'a> From<&'a HeaderName> for HeaderName
Source§fn from(src: &'a HeaderName) -> HeaderName
fn from(src: &'a HeaderName) -> HeaderName
Source§impl From<HeaderName> for HeaderValue
impl From<HeaderName> for HeaderValue
Source§fn from(h: HeaderName) -> HeaderValue
fn from(h: HeaderName) -> HeaderValue
Source§impl FromStr for HeaderName
impl FromStr for HeaderName
Source§type Err = InvalidHeaderName
type Err = InvalidHeaderName
Source§fn from_str(s: &str) -> Result<HeaderName, InvalidHeaderName>
fn from_str(s: &str) -> Result<HeaderName, InvalidHeaderName>
s
to return a value of this type. Read moreSource§impl Hash for HeaderName
impl Hash for HeaderName
Source§impl<'a> PartialEq<&'a HeaderName> for HeaderName
impl<'a> PartialEq<&'a HeaderName> for HeaderName
Source§impl<'a> PartialEq<&'a str> for HeaderName
impl<'a> PartialEq<&'a str> for HeaderName
Source§impl<'a> PartialEq<HeaderName> for &'a HeaderName
impl<'a> PartialEq<HeaderName> for &'a HeaderName
Source§impl<'a> PartialEq<HeaderName> for &'a str
impl<'a> PartialEq<HeaderName> for &'a str
Source§impl PartialEq<HeaderName> for str
impl PartialEq<HeaderName> for str
Source§fn eq(&self, other: &HeaderName) -> bool
fn eq(&self, other: &HeaderName) -> bool
Performs a case-insensitive comparison of the string against the header name
§Examples
use http::header::CONTENT_LENGTH;
assert_eq!(CONTENT_LENGTH, "content-length");
assert_eq!(CONTENT_LENGTH, "Content-Length");
assert_ne!(CONTENT_LENGTH, "content length");