在golang中多次请求后多次关闭响应正文

Question

In this post, it is pointed out that response.Body should be closed to avoid resource leak. It is also shown in the overview examples in http package godoc.

In my test code, I send multiple requests to try an API with

resp, err := http.DefaultClient.Do(req)

multiple times in the same function. Is this a bad practice? In this case, do I write defer resp.Body.Close() after each of them, or just once?

url := server.URL + "/ticket/add"                                       
reader = strings.NewReader(`{"id": "test1", "detail": "test1"}`)        
req, err := http.NewRequest("POST", url, reader)                        
assert.Nil(t, err)               

resp, err := http.DefaultClient.Do(req)                                 
assert.Nil(t, err)                                                      

defer resp.Body.Close()                                                 

assert.Equal(t, http.StatusCreated, resp.StatusCode)                    
// add a ticket with same id                                            
reader = strings.NewReader(`{"id": "test1"}`)                           
req, err = http.NewRequest("POST", url, reader)                         
assert.Nil(t, err)                                                      

resp, err = http.DefaultClient.Do(req)                                  
assert.Nil(t, err)                                                      
assert.Equal(t, http.StatusInternalServerError, resp.StatusCode)   

A related question, on the server side, i.e., inside the func(w http.ResponseWriter, r *http.Request), is it necessary to close the request body as well?

Answer 1

Yes, you need to close both responses. Deferring one call to resp.Body.Close does not somehow effect the other. The *http.Response is different in each case, and they both can be deferred.

On the server side, you do not need to close the Request.Body -- from the http.Request documentation:

// The Server will close the request body. The ServeHTTP
// Handler does not need to.