如何模拟第三方 API 电话？

Question

I have a spring boot application that has the below AuthFilter added for all rest apis exposed by the application. I want to test the below code that validates authorization token by calling a third party api call. I tried Mockito but how do I inject the mocked HttpPost, HttpClient etc object in the filter class? Also what value do I pass to thirdPartyAPIUrl property which is configured in application.properties for test class

@Component
public class AuthTokenFilter implements Filter {

     public boolean isAuthTokenValid(HttpServletRequest request, HttpServletResponse response) throws IOException {
        String authorizationToken = request.getHeader(RequestHeaders.AUTHORIZATION.toString());

        TokenRequest validateTokenRequest = new TokenRequest();
        validateTokenRequest.setToken(authorizationToken);


        try (CloseableHttpClient httpclient = HttpClients.createDefault()) {
            HttpPost httpPost = new HttpPost(this.thirdPartyAPIUrl); //fetched through application.properties
            httpPost.setHeader("Content-type", "application/json");
            StringEntity requestBody = new StringEntity(new Gson().toJson(validateTokenRequest));

            httpPost.setEntity(requestBody);
            try (CloseableHttpResponse validateTokenResponse = httpclient.execute(httpPost)) {
                HttpEntity rEntity = validateTokenResponse.getEntity();
                TokenResponse tokenResponse = new ObjectMapper().readValue(rEntity.getContent(),
                                                                                    TokenResponse.class);
                logger.debug("API Response Object : {}", tokenResponse);
            }
        }

        return false; //temporary
    }
}

Thanks!

Answer 1

I would recommend avoiding mocking HttpPost etc and instead just mocking the third-party server. My preferred tool to use for this is wiremock

Here is an example of how it would be used:

(make sure to import this for options, caused me a lot of headaches;) )

import static com.github.tomakehurst.wiremock.core.WireMockConfiguration.options;

... code

static WireMockServer wireMockServer = new WireMockServer(options().port(8080));

@BeforeAll
static void init() {
    wireMockServer.start();
}

//this is for the case that you have multiple test suites that mock the server, to avoid conflicts with ports
@AfterAll
static void releaseResource() {
        wireMockServer.stop();
    }

@Test
void test() {
    wireMockServer.stubFor(post("/endpoint").willReturn(aResponse().withStatus(200)));

... more code

    filter.isAuthTokenValid(request, response);
}