Expand description
If-None-Match
header, defined
in RFC 7232 §3.2
The If-None-Match
header field makes the request method conditional
on a recipient cache or origin server either not having any current
representation of the target resource, when the field-value is “*”,
or having a selected representation with an entity-tag that does not
match any of those listed in the field-value.
A recipient MUST use the weak comparison function when comparing entity-tags for If-None-Match (Section 2.3.2), since weak entity-tags can be used for cache validation even if there have been changes to the representation data.
ABNF
If-None-Match = "*" / 1#entity-tag
Example Values
"xyzzy"
W/"xyzzy"
"xyzzy", "r2d2xxxx", "c3piozzzz"
W/"xyzzy", W/"r2d2xxxx", W/"c3piozzzz"
*
Examples
use actix_web::HttpResponse;
use actix_web::http::header::IfNoneMatch;
let mut builder = HttpResponse::Ok();
builder.insert_header(IfNoneMatch::Any);
use actix_web::HttpResponse;
use actix_web::http::header::{IfNoneMatch, EntityTag};
let mut builder = HttpResponse::Ok();
builder.insert_header(
IfNoneMatch::Items(vec![
EntityTag::new(false, "xyzzy".to_owned()),
EntityTag::new(false, "foobar".to_owned()),
EntityTag::new(false, "bazquux".to_owned()),
])
);
Variants
Any
Any value is a match
Items(Vec<EntityTag>)
Only the listed items are a match
Trait Implementations
sourceimpl Clone for IfNoneMatch
impl Clone for IfNoneMatch
sourcefn clone(&self) -> IfNoneMatch
fn clone(&self) -> IfNoneMatch
Returns a copy of the value. Read more
1.0.0 · sourcefn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
Performs copy-assignment from source
. Read more
sourceimpl Debug for IfNoneMatch
impl Debug for IfNoneMatch
sourceimpl Display for IfNoneMatch
impl Display for IfNoneMatch
sourceimpl Header for IfNoneMatch
impl Header for IfNoneMatch
sourcefn name() -> HeaderName
fn name() -> HeaderName
Returns the name of the header field
sourcefn parse<M: HttpMessage>(msg: &M) -> Result<Self, ParseError>
fn parse<M: HttpMessage>(msg: &M) -> Result<Self, ParseError>
Parse a header
sourceimpl PartialEq<IfNoneMatch> for IfNoneMatch
impl PartialEq<IfNoneMatch> for IfNoneMatch
sourcefn eq(&self, other: &IfNoneMatch) -> bool
fn eq(&self, other: &IfNoneMatch) -> bool
This method tests for self
and other
values to be equal, and is used
by ==
. Read more
sourcefn ne(&self, other: &IfNoneMatch) -> bool
fn ne(&self, other: &IfNoneMatch) -> bool
This method tests for !=
.
sourceimpl TryIntoHeaderValue for IfNoneMatch
impl TryIntoHeaderValue for IfNoneMatch
type Error = InvalidHeaderValue
type Error = InvalidHeaderValue
The type returned in the event of a conversion error.
sourcefn try_into_value(self) -> Result<HeaderValue, Self::Error>
fn try_into_value(self) -> Result<HeaderValue, Self::Error>
Try to convert value to a HeaderValue.
impl StructuralPartialEq for IfNoneMatch
Auto Trait Implementations
impl RefUnwindSafe for IfNoneMatch
impl Send for IfNoneMatch
impl Sync for IfNoneMatch
impl Unpin for IfNoneMatch
impl UnwindSafe for IfNoneMatch
Blanket Implementations
sourceimpl<T> BorrowMut<T> for T where
T: ?Sized,
impl<T> BorrowMut<T> for T where
T: ?Sized,
const: unstable · sourcefn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more
sourceimpl<T> Instrument for T
impl<T> Instrument for T
sourcefn instrument(self, span: Span) -> Instrumented<Self>
fn instrument(self, span: Span) -> Instrumented<Self>
sourcefn in_current_span(self) -> Instrumented<Self>
fn in_current_span(self) -> Instrumented<Self>
sourceimpl<T> TryIntoHeaderPair for T where
T: Header,
impl<T> TryIntoHeaderPair for T where
T: Header,
type Error = <T as TryIntoHeaderValue>::Error
fn try_into_pair(
self
) -> Result<(HeaderName, HeaderValue), <T as TryIntoHeaderPair>::Error>
sourceimpl<T> WithSubscriber for T
impl<T> WithSubscriber for T
sourcefn with_subscriber<S>(self, subscriber: S) -> WithDispatch<Self> where
S: Into<Dispatch>,
fn with_subscriber<S>(self, subscriber: S) -> WithDispatch<Self> where
S: Into<Dispatch>,
Attaches the provided Subscriber
to this type, returning a
WithDispatch
wrapper. Read more
sourcefn with_current_subscriber(self) -> WithDispatch<Self>
fn with_current_subscriber(self) -> WithDispatch<Self>
Attaches the current default Subscriber
to this type, returning a
WithDispatch
wrapper. Read more