http request mocking code samples

interface_approach_test.go

func TestGetFixedValue(t *testing.T) {
   Client = &MockClient{
       DoFunc: func(req *http.Request) (*http.Response, error) {
           if req.URL.Path != "/fixedvalue" {
               t.Errorf("Expected to request '/fixedvalue', got: %s", req.URL.Path)
           }
           if req.Header.Get("Accept") != "application/json" {
               t.Errorf("Expected Accept: application/json header, got: %s", req.Header.Get("Accept"))
           }
 
           responseBody := ioutil.NopCloser(bytes.NewReader([]byte(`{"value":"fixed"}`)))
           return &http.Response{
               StatusCode: 200,
               Body:       responseBody,
           }, nil
       },
   }
 
   value, _ := GetFixedValue("https://example.com")
   if value != "fixed" {
       t.Errorf("Expected 'fixed', got %s", value)
   }
}