override fun install()

in ktor-server/ktor-server-core/jvm/src/io/ktor/features/CallId.kt [192:237]
38 lines of code
6 McCabe index (conditional complexity)

        override fun install(pipeline: ApplicationCallPipeline, configure: Configuration.() -> Unit): CallId {
            val configuration = Configuration().apply(configure)

            val instance = CallId(
                providers = (configuration.retrievers + configuration.generators).toTypedArray(),
                repliers = configuration.responseInterceptors.toTypedArray(),
                verifier = configuration.verifier
            )

            pipeline.insertPhaseBefore(ApplicationCallPipeline.Setup, phase)

            if (instance.providers.isEmpty()) {
                logger.warn("CallId feature is not configured: neither retrievers nor generators were configured")
                return instance // don't install interceptor
            }

            pipeline.intercept(phase) {
                val call = call
                val providers = instance.providers

                try {
                    for (i in 0 until providers.size) {
                        val callId = providers[i](call) ?: continue
                        if (!instance.verifier(callId)) continue // could throw a RejectedCallIdException

                        call.attributes.put(callIdKey, callId)

                        val repliers = instance.repliers
                        for (j in 0 until repliers.size) {
                            repliers[j](call, callId)
                        }
                        break
                    }
                } catch (rejection: RejectedCallIdException) {
                    logger.warn(
                        "Illegal call id retrieved or generated that is rejected by call id verifier:" +
                            " (url-encoded) " +
                            rejection.illegalCallId.encodeURLParameter()
                    )
                    call.respond(HttpStatusCode.BadRequest)
                    finish()
                }
            }

            return instance
        }