fix the review comments to use httptest package

Signed-off-by: Ziqi Zhao <[email protected]>

config/confighttp/compression_test.go

@@ -22,6 +22,7 @@ import (
 	"io/ioutil"
 	"net"
 	"net/http"
+	"net/http/httptest"
 	"testing"
 	"time"
 
@@ -233,38 +234,27 @@ func TestHTTPContentDecompressionHandler(t *testing.T) {
 	}
 }
 
-func TestHTTPContentCompressionNilRequestBody(t *testing.T) {
-	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+func TestHTTPContentCompressionRequestWithNilBody(t *testing.T) {
+	compressedGzipBody, _ := compressGzip([]byte{})
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		w.WriteHeader(200)
-	})
+		body, err := ioutil.ReadAll(r.Body)
+		require.NoError(t, err, "failed to read request body: %v", err)
+		assert.EqualValues(t, compressedGzipBody.Bytes(), body)
+	}))
+	defer server.Close()
 
-	addr := testutil.GetAvailableLocalAddress(t)
-	ln, err := net.Listen("tcp", addr)
-	require.NoError(t, err, "failed to create listener: %v", err)
-	srv := &http.Server{
-		Handler: handler,
-	}
-	go func() {
-		_ = srv.Serve(ln)
-	}()
-	// Wait for the servers to start
-	<-time.After(10 * time.Millisecond)
-
-	serverURL := fmt.Sprintf("http://%s", ln.Addr().String())
-
-	req, err := http.NewRequest("GET", serverURL, nil)
+	req, err := http.NewRequest("GET", server.URL, nil)
 	require.NoError(t, err, "failed to create request to test handler")
 
 	client := http.Client{}
 	client.Transport = newCompressRoundTripper(http.DefaultTransport, configcompression.Gzip)
-
 	res, err := client.Do(req)
 	require.NoError(t, err)
 
 	_, err = ioutil.ReadAll(res.Body)
 	require.NoError(t, err)
 	require.NoError(t, res.Body.Close(), "failed to close request body: %v", err)
-	require.NoError(t, srv.Close())
 }
 
 func compressGzip(body []byte) (*bytes.Buffer, error) {