Available-Dictionary header

The HTTP Available-Dictionary request header allows the browser to specify the best matching dictionary it has to allow the server to use Compression Dictionary Transport for a resource request.

Clients can send an Available-Dictionary header when they support dcb or dcz encodings. The header is a colon-surrounded base-64 encoded SHA-256 hash of the dictionary contents.

See the Compression Dictionary Transport guide for more information.

Syntax

Available-Dictionary: :<base64-hash>:

Directives

<base64-hash>
- : A base-64 encoded SHA-256 hash of the dictionary contents.

Examples

Accept-Encoding: gzip, br, zstd, dcb, dcz
Available-Dictionary: :pZGm1Av0IEBKARczz7exkNYsZb8LzaMrV7J32a2fFG4=:

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