使用mockito模拟HttpClient请求

Question

我希望使用 Junit 和 Mockito 测试以下代码。

要测试的代码：

    Header header = new BasicHeader(HttpHeaders.AUTHORIZATION,AUTH_PREAMBLE + token);
    List<Header> headers = new ArrayList<Header>();
    headers.add(header);
    HttpClient client = HttpClients.custom().setDefaultHeaders(headers).build();
    HttpGet get = new HttpGet("real REST API here"));
    HttpResponse response = client.execute(get);
    String json_string_response = EntityUtils.toString(response.getEntity());

和测试

protected static HttpClient mockHttpClient;
protected static HttpGet mockHttpGet;
protected static HttpResponse mockHttpResponse;
protected static StatusLine mockStatusLine;
protected static HttpEntity mockHttpEntity;





@BeforeClass
public static void setup() throws ClientProtocolException, IOException {
    mockHttpGet = Mockito.mock(HttpGet.class);
    mockHttpClient = Mockito.mock(HttpClient.class);
    mockHttpResponse = Mockito.mock(HttpResponse.class);
    mockStatusLine = Mockito.mock(StatusLine.class);
    mockHttpEntity = Mockito.mock(HttpEntity.class);

    Mockito.when(mockHttpClient.execute(Mockito.isA(HttpGet.class))).thenReturn(mockHttpResponse);
    Mockito.when(mockHttpResponse.getStatusLine()).thenReturn(mockStatusLine);
    Mockito.when(mockStatusLine.getStatusCode()).thenReturn(HttpStatus.SC_OK);
    Mockito.when(mockHttpResponse.getEntity()).thenReturn(mockHttpEntity);

}


@Test
underTest = new UnderTest(initialize with fake API (api));
//Trigger method to test

这给了我一个错误：

java.net.UnknownHostException：api：提供节点名或服务名，或未知

为什么不按照'client.execute(get)'设置中的方式模拟呼叫？

Answer 1

到目前为止你所拥有的是：

mockHttpClient = Mockito.mock(HttpClient.class);
Mockito.when(mockHttpClient.execute(Mockito.isA(HttpGet.class))).thenReturn(mockHttpResponse)

因此，有一个模拟应该对 的调用做出反应execute()。

然后你有：

1) underTest = new UnderTest(initialize with fake API (api));
2) // Trigger method to test

问题是：您的设置中的第 1 行或第 2 行有问题。但我们不能告诉你；因为您没有向我们提供该代码。

问题是：为了让你的模拟对象有用，它需要被underTest以某种方式使用。因此，当您以某种方式错误地执行初始化操作时，underTest 不会使用模拟的东西，而是使用一些“真实”的东西。