Speedup tests of play.libs.ws.WSClient that use a play.server.Server

[simonlucalandi]

In our platform, based on PlayFramework 2.8, we have several external API that we call using play.libs.ws.WSClient.
To test the behavior of the WSClient, we start a local play.server.Server, configured to serve the expected resources, something like this:

 @Test
 public void myTest() {
        System.out.println(ZonedDateTime.now());
        play.server.Server server = Server.forRouter((components) -> RoutingDsl.fromComponents(components)
                .POST("/").routingTo(request -> ok().sendResource("test1.json")
                ).build()
        );
        System.out.println(ZonedDateTime.now());

        play.libs.ws.WSClient ws = play.test.WSTestClient.newClient(server.httpPort());
		
		// here we use ws to make a request to "server" and verify the response.
		MyClient client = new MyClient(ws);
		var response = client.myMethod();
		assertAllGood(response);
    }
	

As we test the behavior for different served resources, we need to start again and again a new Server for each test, and the test suite is now slooooow.
Starting the server takes around 300-400 ms (measured with the System.out.println(ZonedDateTime.now()) that you see in the code).
Is there a way to speedup the tests? For example I was looking for a a way to reuse the same Server, changing only the Routing, but I can't find a way.
Any suggestion is appreciated.

[domdorn]

have you tried extracting the server out of your method scope? e.g.

        play.server.Server server = Server.forRouter((components) -> RoutingDsl.fromComponents(components)
                .POST("/").routingTo(request -> ok().sendResource("test1.json")
                ).build()
        );

 @Test
 public void myTest() {

        play.libs.ws.WSClient ws = play.test.WSTestClient.newClient(server.httpPort());
		
		// here we use ws to make a request to "server" and verify the response.
		MyClient client = new MyClient(ws);
		var response = client.myMethod();
		assertAllGood(response);
    }

[wsargent]

You can dependency inject the AsyncHttpClient instance between runs using injection. It doesn't need to be restarted between applications.

[simonlucalandi]

Can you elaborate a bit more on this please?
Let's say that we have a test class like this:

@Test
 public void myTest1() {
        play.server.Server server = Server.forRouter((components) -> RoutingDsl.fromComponents(components)
                .POST("/").routingTo(request -> ok().sendResource("test1.json")
                ).build()
        );
        play.libs.ws.WSClient ws = play.test.WSTestClient.newClient(server.httpPort());
		
		// here we use ws to make a request to "server" and verify the response.
		MyClient client = new MyClient(ws);
		var response = client.myMethod();
		assertAllGood2(response);
    }

@Test
 public void myTest2() {
        play.server.Server server = Server.forRouter((components) -> RoutingDsl.fromComponents(components)
                .POST("/").routingTo(request -> ok().sendResource("test2.json")  // NOTE: here we serve, for the same path "/", a different response to test a different expected behaviour
                ).build()
        );

        play.libs.ws.WSClient ws = play.test.WSTestClient.newClient(server.httpPort());
		
		// here we use ws to make a request to "server" and verify the response.
		MyClient client = new MyClient(ws);
		var response = client.myMethod();
		assertAllGood2(response);
    }

How do you suggest to refactor the test code to increase the speed?