sparkjava-testing

A small testing library for spinning up a Spark server for functional testing of HTTP clients.

Example usage

See the actual tests for example usage. But if you don't want to do that, here's a short example that uses the JUnit Jupiter extension.

First, annotate your test with @ExtendWith(JavaSparkRunnerExtension.class). Then, create a @BeforeAll method that accepts a SparkStarter, which allows you to define the various HTTP routes. Then your tests run, making HTTP requests to the test server, and finally the server is shut down after tests have run. The injection can be done in several places e.g. in methods annotated with @BeforeEach @BeforeAll or even @Test.

@BeforeAll
static void beforeAll(SparkStarter s) {
    s.runSpark(http -> {
        http.get("/ping", (request, response) -> "pong");
        http.get("/health", (request, response) -> "healthy");
    });
}

In the above example, there are two routes, /ping and /health, specified in the lambda which simply return 200 responses containing strings. Here's an example test using a Jersey client (I'm using AssertJ assertions in this test):

@Test
public void testSparkServerRule_PingRequest() {
    client = ClientBuilder.newBuilder().build();
    Response response = client.target(URI.create("http://localhost:4567/ping"))
            .request()
            .get();
    assertThat(response.getStatus()).isEqualTo(200);
    assertThat(response.readEntity(String.class)).isEqualTo("pong");
}

Since Spark runs on port 4567 by default that's the port our client test uses. Also, the client is closed in a test tear down method.

If you want to run the test on a different port you could do it as follows:

@BeforeAll
static void setUp(SparkStarter s) {
    s.runSpark(http -> {
        http.port(9876);
        http.get("/ping", (request, response) -> "pong");
        http.get("/health", (request, response) -> "healthy");
    });
}

And if you want to change not only the port, but also the IP address and make the server secure, you can do it like this:

@BeforeAll
static void setUp(SparkStarter s) {
    s.runSpark(https -> {
        https.ipAddress("127.0.0.1");
        https.port(9876);
        URL resource = Resources.getResource("sample-keystore.jks");
        https.get("/ping", (request, response) -> "pong");
        https.get("/health", (request, response) -> "healthy");
    });
}

See the actual unit tests for concrete examples.