Struct headers_ext::IfRange

pub struct IfRange(_);

If-Range header, defined in RFC7233

If a client has a partial copy of a representation and wishes to have an up-to-date copy of the entire representation, it could use the Range header field with a conditional GET (using either or both of If-Unmodified-Since and If-Match.) However, if the precondition fails because the representation has been modified, the client would then have to make a second request to obtain the entire current representation.

The If-Range header field allows a client to "short-circuit" the second request. Informally, its meaning is as follows: if the representation is unchanged, send me the part(s) that I am requesting in Range; otherwise, send me the entire representation.

ABNF

If-Range = entity-tag / HTTP-date

Example values

• Sat, 29 Oct 1994 19:43:31 GMT
• \"xyzzy\"

Examples

use headers::IfRange;
use std::time::{SystemTime, Duration};

let fetched = SystemTime::now() - Duration::from_secs(60 * 60 * 24);
let if_range = IfRange::date(fetched);

Implementations

impl IfRange

pub fn etag(tag: ETag) -> IfRange

Create an IfRange header with an entity tag.

pub fn date(time: SystemTime) -> IfRange

Create an IfRange header with a date value.

pub fn is_modified(
    &self,
    _etag: Option<&ETag>,
    last_modified: Option<&LastModified>
) -> bool

Checks if the resource has been modified, or if the range request can be served.

Trait Implementations

impl Clone for IfRange

fn clone(&self) -> IfRange

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for IfRange

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

Formats the value using the given formatter.

impl Header for IfRange

const NAME: &'static HeaderName = _

The name of this header.

fn decode<'i, I>(values: &mut I) -> Result<Self, Error>where
    I: Iterator<Item = &'i HeaderValue>,

Decode this type from an iterator of HeaderValues.

fn encode<E: Extend<HeaderValue>>(&self, values: &mut E)

Encode this type to a HeaderMap.

impl PartialEq<IfRange> for IfRange

fn eq(&self, other: &IfRange) -> 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 !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for IfRange