CompressionCopy Anchor Link

Ktor's Compression plugin does the encode/decode work. UnaryCompressionGuard decides which encodings a Connect unary route will accept before the body is parsed.

Unsupported Content-Encoding values are rejected with Code.UNIMPLEMENTED.

Minimal setupCopy Anchor Link

embeddedServer(CIO, port = 8080) {
    install(Resources)
    install(Compression) {
        gzip()
        identity()
    }
    routing {
        install(UnaryCompressionGuard) {
            supportedEncodings = setOf("gzip", "identity")
        }
        connectBodyLimit(maxBytes = 4 * 1024 * 1024)
        install(ContentNegotiation) {
            connectJson()
        }
        elizaService(ElizaServiceHandler)
    }
}.start(wait = true)

Keep supportedEncodings aligned with the encoders you actually registered. Listing br without a brotli encoder only produces opaque parse failures later.

StreamingCopy Anchor Link

Client-streaming paths suppress Ktor compression around the envelope body. Per-message gzip for client-stream RPCs is still unimplemented; those conformance cases stay known-failing.

Encoding namesCopy Anchor Link

Names are matched case-sensitively (except identity), matching Ktor's decoder lookup. Content-Encoding: GZIP is rejected even though some stacks treat encoding tokens as case-insensitive.