pub enum IfNoneMatch {
    Any,
    Items(Vec<EntityTag>),
}
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§

Returns a copy of the value. Read more
Performs copy-assignment from source. Read more
Formats the value using the given formatter. Read more
Formats the value using the given formatter. Read more
Returns the name of the header field.
Parse the header from a HTTP message.
This method tests for self and other values to be equal, and is used by ==.
This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.
The type returned in the event of a conversion error.
Try to convert value to a HeaderValue.

Auto Trait Implementations§

Blanket Implementations§

Gets the TypeId of self. Read more
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Compare self to key and return true if they are equal.

Returns the argument unchanged.

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Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

Should always be Self
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Uses borrowed data to replace owned data, usually by cloning. Read more
Converts the given value to a String. Read more
The type returned in the event of a conversion error.
Performs the conversion.
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Performs the conversion.
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