On Async Http Client documentation I see how to get a Future<Response>
as the result of an asynchronous HTTP Get request simply doing, for example:
AsyncHttpClient asyncHttpClient = new DefaultAsyncHttpClient();
Future<Response> f = asyncHttpClient
.prepareGet("http://api.football-data.org/v1/soccerseasons/398")
.execute();
Response r = f.get();
However, for convenience I would like to get a CompletableFuture<T>
instead, for which I could apply a continuation that converts the result in something else, for instance deserializing the response content from Json into a Java object (e.g. SoccerSeason.java). This is what I would like to do:
AsyncHttpClient asyncHttpClient = new DefaultAsyncHttpClient();
CompletableFuture<Response> f = asyncHttpClient
.prepareGet("http://api.football-data.org/v1/soccerseasons/398")
.execute();
f
.thenApply(r -> gson.fromJson(r.getResponseBody(), SoccerSeason.class))
.thenAccept(System.out::println);
According to Async Http Client documentation the only way to do this is through an AsyncCompletionHandler<T>
object and using a promise. So I built an auxiliary method to that end:
CompletableFuture<Response> getDataAsync(String path){
CompletableFuture<Response> promise = new CompletableFuture<>();
asyncHttpClient
.prepareGet(path)
.execute(new AsyncCompletionHandler<Response>() {
@Override
public Response onCompleted(Response response) throws Exception {
promise.complete(response);
return response;
}
@Override
public void onThrowable(Throwable t) {
promise.completeExceptionally(t);
}
});
return promise;
}
With this utility method I can rewrite the previous example just doing:
getDataAsync("http://api.football-data.org/v1/soccerseasons/398")
.thenApply(r -> gson.fromJson(r.getResponseBody(), SoccerSeason.class))
.thenAccept(System.out::println);
Is there any better way of getting a CompletableFuture<T>
from an Async Http Client request?
With AHC2:
CompletableFuture<Response> f = asyncHttpClient
.prepareGet("http://api.football-data.org/v1/soccerseasons/398")
.execute()
.toCompletableFuture();