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You are viewing the documentation for the 2.1.1 release in the 2.1.x series of releases. The latest stable release series is 2.5.x.

§The Play WS API

Sometimes you want to call other HTTP services from within a Play application. Play supports this via its play.libs.WS library, which provides a way to make asynchronous HTTP calls.

A call made by play.libs.WS should return a Promise<Ws.Response>, which you can handle later with Play’s asynchronous mechanisms.

§Making HTTP calls

To make an HTTP request, you start with WS.url() to specify the URL. Then you get a builder that you can use to specify HTTP options, such as setting headers. You end by calling a method corresponding to the HTTP method you want to use:

Promise<WS.Response> homePage = WS.url("http://mysite.com").get();

Alternatively:

Promise<WS.Response> result = WS.url("http://localhost:9001").post("content");

§Retrieving the HTTP response result

The call is made asynchronously and you need to manipulate it as a Promise<WS.Response> to get the actual content. You can compose several promises and end up with a Promise<Result> that can be handled directly by the Play server:

import play.libs.F.Function;
import play.libs.WS;
import play.mvc.*;

public class Controller extends Controller {

  public static Result feedTitle(String feedUrl) {
    return async(
      WS.url(feedUrl).get().map(
        new Function<WS.Response, Result>() {
          public Result apply(WS.Response response) {
            return ok("Feed title:" + response.asJson().findPath("title"));
          }
        }
      )
    );
  }
  
}

§Composing results

If you want to make multiple calls in sequence, this can be achieved using flatMap:

  public static Result feedComments(String feedUrl) {
    return async(
      WS.url(feedUrl).get().flatMap(
        new Function<WS.Response, Promise<Result>>() {
          public Promise<Result> apply(WS.Response response) {
            return WS.url(response.asJson().findPath("commentsUrl").get().map(
              new Function<WS.Response, Result>() {
                public Result apply(WS.Response response) {
                  return ok("Number of comments: " + response.asJson().findPath("count"));
                }
              }
            );
          }
        }
      )
    );
  }

§Configuring the HTTP client

The HTTP client can be configured globally in application.conf via a few properties:

# Follow redirects (default true)
ws.followRedirects=true
# Connection timeout in ms (default 120000)
ws.timeout=120000
# Whether to use http.proxy* JVM system properties (default true)
ws.useProxyProperties=true
# A user agent string to set on each request (default none)
ws.useragent="My Play Application"

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