compress

Documentation

Overview

Package compress handles Content-Encoding compression for HTTP body inspection.

Typical usage in a response body handler:

decoded, err := compress.Decode(chunk.ContentEncoding, chunk.Data)

To prevent upstream from sending compressed responses, call RequestIdentity from the request headers handler instead:

func onReq(w *up.Writer, r *up.Request) { compress.RequestIdentity(w) }

Index

• func AcceptEncodingAllSupported(acceptEncoding string) bool
• func Decode(encoding string, data []byte) ([]byte, error)
• func Encode(encoding string, data []byte) ([]byte, error)
• func RequestIdentity(h RequestHeaderSetter)
• type RequestHeaderSetter

Functions

func AcceptEncodingAllSupported

func AcceptEncodingAllSupported(acceptEncoding string) bool

AcceptEncodingAllSupported reports whether every encoding token in an Accept-Encoding header value is one that Decode can handle. Quality values (e.g. ;q=0.9) are ignored: the upstream performs actual negotiation and we will only receive an encoding that the upstream chose to use. The wildcard "*" always returns false because any encoding could be selected.

func Decode

func Decode(encoding string, data []byte) ([]byte, error)

Decode decompresses data according to the Content-Encoding header value. Supports "gzip", "deflate", "zstd", "br", "identity", and "". Returns data unchanged for identity or empty encoding.

func Encode

func Encode(encoding string, data []byte) ([]byte, error)

Encode compresses data with the given encoding. Supports "gzip", "deflate", "zstd", "br", "identity", and "".

func RequestIdentity

func RequestIdentity(h RequestHeaderSetter)

RequestIdentity sets Accept-Encoding: identity on the outgoing request so upstream responds with uncompressed bodies. Call from OnRequestHeaders. This is the preferred strategy; use Decode as a fallback for upstreams that ignore Accept-Encoding (some CDNs always compress).

Types

type RequestHeaderSetter

type RequestHeaderSetter interface {
	SetRequestHeader(name, value string)
}

RequestHeaderSetter is implemented by types that can rewrite outgoing request headers.