encodeResponse

Tries to encode the response with the specified Encoder or rejects the request with an UnacceptedResponseEncodingRejection(supportedEncodings).

Signature

def encodeResponse(encoder: Encoder)(implicit refFactory: ActorRefFactory): Directive0
def encodeResponse(encoder: Encoder, threshold: Long, maxChunkSize: Long)
                   (implicit refFactory: ActorRefFactory): Directive0

The signature shown is simplified, the real signature uses magnets. [1]

[1]	See The Magnet Pattern for an explanation of magnet-based overloading.

Description

The directive automatically applies the autoChunkFileBytes directive as well to avoid having to load an entire file into JVM heap.

The parameter to the directive is either just an Encoder or all of an Encoder, a threshold, and a chunk size to configure the automatically applied autoChunkFileBytes directive.

The encodeResponse directive is the building block for the compressResponse and compressResponseIfRequested directives.

encodeResponse, compressResponse, and compressResponseIfRequested are related like this:

compressResponse(Gzip)          = encodeResponse(Gzip)
compressResponse(a, b, c)       = encodeResponse(a) | encodeResponse(b) | encodeResponse(c)
compressResponse()              = encodeResponse(Gzip) | encodeResponse(Deflate) | encodeResponse(NoEncoding)
compressResponseIfRequested()   = encodeResponse(NoEncoding) | encodeResponse(Gzip) | encodeResponse(Deflate)

Example

val route = encodeResponse(Gzip) { complete("content") }

Get("/") ~> route ~> check {
  response must haveContentEncoding(gzip)
}
Get("/") ~> `Accept-Encoding`(gzip, deflate) ~> route ~> check {
  response must haveContentEncoding(gzip)
}
Get("/") ~> `Accept-Encoding`(deflate) ~> route ~> check {
  rejection === UnacceptedResponseEncodingRejection(gzip)
}
Get("/") ~> `Accept-Encoding`(identity) ~> route ~> check {
  rejection === UnacceptedResponseEncodingRejection(gzip)
}