OkHttp MockWebServer fails to accept connections when restarted

Nitzan Tomer picture Nitzan Tomer · Jun 22, 2016 · Viewed 11.5k times · Source

I'm using the OkHttp MockWebServer to mock my server responses for unit tests.

It works great for the first test, but on the 2nd test my client fails with:

Failed to connect to localhost/0:0:0:0:0:0:0:1:63631

This happens even if the 2nd test is exactly the same as the 1st one.
Here's what I'm doing:

@RunWith(RobolectricTestRunner.class)
@Config(shadows = MyClassTest.MyNetworkSecurityPolicy.class,
        manifest = "src/main/AndroidManifest.xml",
        constants = BuildConfig.class,
        sdk = 16)
public class MyClassTest {
    private MockWebServer mockServer;
    private MyServerApi serverApi;

    @Before
    public void setUp() throws Exception {
        System.out.println("\ntest start");
        this.mockServer = new MockWebServer();
        this.mockServer.start();

        this.serverApi = new MyServerApi(this.mockServer.url("/").toString());
    }

    @Test
    public void testOne() throws Exception {
        final String responseBody = // read response from file
        this.mockServer.enqueue(new MockResponse().setResponseCode(200).setBody(responseBody));

        final Waiter waiter = new Waiter();
        this.serverApi.getData("some_id", new Callback<MyResponseData> {
            @Override
            public void onResponse(final Call<MyResponseData> call, final Response<MyResponseData> response) {
                waiter.assertEquals("some_value", response.body().getValue());
                waiter.resume();
            }

            @Override
            public void onFailure(final Call<T> call, final Throwable error) {
                waiter.fail(error);
            }
        });

        waiter.await();

        final RecordedRequest recordedRequest = this.mockServer.takeRequest();
        assertEquals("GET", recordedRequest.getMethod());
    }

    @Test
    public void testTwo() throws Exception {
        final String responseBody = // read response from file
        this.mockServer.enqueue(new MockResponse().setResponseCode(200).setBody(responseBody));

        final Waiter waiter = new Waiter();
        this.serverApi.getData("some_id", new Callback<MyResponseData> {
            @Override
            public void onResponse(final Call<MyResponseData> call, final Response<MyResponseData> response) {
                waiter.assertEquals("some_value", response.body().getValue());
                waiter.resume();
            }

            @Override
            public void onFailure(final Call<T> call, final Throwable error) {
                waiter.fail(error);
            }
        });

        waiter.await();

        final RecordedRequest recordedRequest = this.mockServer.takeRequest();
        assertEquals("GET", recordedRequest.getMethod());
    }

    @After
    public void tearDown() throws Exception {
        System.out.println("test end\n");
        this.mockServer.shutdown();
    }

    @Implements(NetworkSecurityPolicy.class)
    public static class MyNetworkSecurityPolicy {
        @Implementation
        public static NetworkSecurityPolicy getInstance() {
            try {
                Class<?> shadow = MyNetworkSecurityPolicy.class.forName("android.security.NetworkSecurityPolicy");
                return (NetworkSecurityPolicy) shadow.newInstance();
            } catch (Exception e) {
                throw new AssertionError();
            }
        }

        @Implementation
        public boolean isCleartextTrafficPermitted() {
            return true;
        }
    }
}

The first test passes as it should, but the second one fails with the message I wrote above.
The output in the console is:

test start
okhttp3.mockwebserver.MockWebServer$3 execute
INFO: MockWebServer[63631] starting to accept connections
WARNING: no system properties value for gsm.sim.operator.alpha
okhttp3.mockwebserver.MockWebServer$4 processOneRequest
INFO: MockWebServer[63631] received request: GET REQUEST_PATH HTTP/1.1 and responded: HTTP/1.1 200 OK
okhttp3.mockwebserver.MockWebServer$3 acceptConnections
test end

INFO: MockWebServer[63631] done accepting connections: Socket closed

test start
okhttp3.mockwebserver.MockWebServer$3 execute
INFO: MockWebServer[63649] starting to accept connections
okhttp3.mockwebserver.MockWebServer$3 acceptConnections
INFO: MockWebServer[63649] done accepting connections: Socket closed
on error: Failed to connect to localhost/0:0:0:0:0:0:0:1:63631
test end

(The Waiter object thing is from the concurrentunit lib)

Any idea why this happens?

Answer

Jesse Wilson picture Jesse Wilson · Jun 22, 2016

Your second request is using the URL of the first MockWebServer instance. (Each instance has a distinct URL.)