Struct http::header::HeaderName
source · [−]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
sourceimpl 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
sourceimpl AsRef<[u8]> for HeaderName
impl AsRef<[u8]> for HeaderName
sourceimpl AsRef<str> for HeaderName
impl AsRef<str> for HeaderName
sourceimpl Borrow<str> for HeaderName
impl Borrow<str> for HeaderName
sourceimpl Clone for HeaderName
impl Clone for HeaderName
sourcefn clone(&self) -> HeaderName
fn clone(&self) -> HeaderName
1.0.0 · sourcefn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresourceimpl Debug for HeaderName
impl Debug for HeaderName
sourceimpl Display for HeaderName
impl Display for HeaderName
sourceimpl<'a> From<&'a HeaderName> for HeaderName
impl<'a> From<&'a HeaderName> for HeaderName
sourcefn from(src: &'a HeaderName) -> HeaderName
fn from(src: &'a HeaderName) -> HeaderName
sourceimpl From<HeaderName> for HeaderValue
impl From<HeaderName> for HeaderValue
sourcefn from(h: HeaderName) -> HeaderValue
fn from(h: HeaderName) -> HeaderValue
sourceimpl FromStr for HeaderName
impl FromStr for HeaderName
type Err = InvalidHeaderName
type Err = InvalidHeaderName
sourcefn from_str(s: &str) -> Result<HeaderName, InvalidHeaderName>
fn from_str(s: &str) -> Result<HeaderName, InvalidHeaderName>
s
to return a value of this type. Read moresourceimpl Hash for HeaderName
impl Hash for HeaderName
sourceimpl<'a> PartialEq<&'a HeaderName> for HeaderName
impl<'a> PartialEq<&'a HeaderName> for HeaderName
sourcefn eq(&self, other: &&'a HeaderName) -> bool
fn eq(&self, other: &&'a HeaderName) -> bool
sourceimpl<'a> PartialEq<&'a str> for HeaderName
impl<'a> PartialEq<&'a str> for HeaderName
sourceimpl<'a> PartialEq<HeaderName> for &'a HeaderName
impl<'a> PartialEq<HeaderName> for &'a HeaderName
sourcefn eq(&self, other: &HeaderName) -> bool
fn eq(&self, other: &HeaderName) -> bool
sourceimpl<'a> PartialEq<HeaderName> for &'a str
impl<'a> PartialEq<HeaderName> for &'a str
sourcefn eq(&self, other: &HeaderName) -> bool
fn eq(&self, other: &HeaderName) -> bool
Performs a case-insensitive comparison of the string against the header name
sourceimpl PartialEq<HeaderName> for HeaderName
impl PartialEq<HeaderName> for HeaderName
sourcefn eq(&self, other: &HeaderName) -> bool
fn eq(&self, other: &HeaderName) -> bool
sourceimpl PartialEq<HeaderName> for str
impl PartialEq<HeaderName> for str
sourcefn 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");