Nrthugu

I am new to AKKA , I am trying to fire away the 3 requests, set a timeout to ~1 second for each to complete, aggregate the results. The 3 requests or multiple requests will be simple API call , GET, where the response from the API will be in JSON. So far the code I have

        final ActorSystem system = ActorSystem.create();

    final ActorMaterializer materializer = ActorMaterializer.create(system);



    final Flow<HttpRequest, HttpResponse, CompletionStage<OutgoingConnection>> connectionFlow =

            Http.get(system).outgoingConnection(toHost("https://example/api/ticker", 80));

    final CompletionStage<HttpResponse> responseFuture =

            Source.single(HttpRequest.create("/"))

                    .via(connectionFlow)

                    .runWith(Sink.<HttpResponse>head(), materializer).;

Any help regarding this will be highly appreciated.

I am not too familiar with the java version of akka so the below example code may not be compile-able but it demonstrates the general idea...

Presumably you have functions for converting the response from previous API calls into requests for the next API:

public static HttpRequest convertAPI1Response(HttpResponse httpResponse) {



}



public static HttpRequest convertAPI2Response(HttpResponse httpResponse) {



}

These converters can then be placed inside Flow values:

final Flow<HttpResponse, HttpRequest, ...> convertAPI1Flow = 

  Flow.of(HttpResponse.class).map(convertAPI1Response)



final Flow<HttpResponse, HttpRequest, ...> convertAPI2Flow = 

  Flow.of(HttpResponse.class).map(convertAPI1Response)

These Flows can now be used in concert with the outgoingConnection flows that the question already references:

final Flow<HttpRequest, HttpResponse, CompletionStage<OutgoingConnection>> connection1Flow =

        Http.get(system).outgoingConnection(toHost("https://example/api/ticker", 80));



final Flow<HttpRequest, HttpResponse, CompletionStage<OutgoingConnection>> connection2Flow =

        Http.get(system).outgoingConnection(toHost("https://someOtherHost.com/api", 80));



final Flow<HttpRequest, HttpResponse, CompletionStage<OutgoingConnection>> connection3Flow =

        Http.get(system).outgoingConnection(toHost("https://someOtherOtherHost.com/api", 80));

And finally, all of the Flows can be connected together:

final CompletionStage<HttpResponse> responseFuture =

        Source.single(HttpRequest.create("/"))

              .via(connection1Flow)

              .via(convertAPI1Flow)

              .via(connection2Flow)

              .via(convertAPI2Flow)

              .via(connection3Flow)

              .runWith(Sink.<HttpResponse>head(), materializer).;