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Conditionals

Overview​

Usage​

import { Conditionals } from 'keywork/http/headers'

Properties​

ETag​

ETag: `string`

A unique string identifying the version of the resource. Conditional requests using "If-Match" and "If-None-Match" use this value to change the behavior of the request.

Defined in​

http/headers/mod.ts:166

If-Match​

If-Match: `string`

Makes the request conditional, and applies the method only if the stored resource matches one of the given ETags.

Defined in​

http/headers/mod.ts:170

If-Modified-Since​

If-Modified-Since: `string`

Makes the request conditional, and expects the resource to be transmitted only if it has been modified after the given date. This is used to transmit data only when the cache is out of date.

Defined in​

http/headers/mod.ts:180

If-None-Match​

If-None-Match: `string`

Makes the request conditional, and applies the method only if the stored resource doesn't match any of the given ETags. This is used to update caches (for safe requests), or to prevent uploading a new resource when one already exists.

Defined in​

http/headers/mod.ts:174

If-Unmodified-Since​

If-Unmodified-Since: `string`

Makes the request conditional, and expects the resource to be transmitted only if it has not been modified after the given date. This ensures the coherence of a new fragment of a specific range with previous ones, or to implement an optimistic concurrency control system when modifying existing documents.

Defined in​

http/headers/mod.ts:186

Last-Modified​

Last-Modified: `string`

The last modification date of the resource, used to compare several versions of the same resource. It is less accurate than "ETag", but easier to calculate in some environments. Conditional requests using "If-Modified-Since" and "If-Unmodified-Since" use this value to change the behavior of the request.

Defined in​

http/headers/mod.ts:161

Vary​

Vary: `string`

Determines how to match request headers to decide whether a cached response can be used rather than requesting a fresh one from the origin server.

Defined in​

http/headers/mod.ts:191