Support body with GET method

Author: luominggang

header.go

@@ -1594,19 +1594,14 @@ func (h *RequestHeader) AppendBytes(dst []byte) []byte {
 		dst = appendHeaderLine(dst, strHost, host)
 	}
 
+	// TODO: Here just for a proxy server. For a normal client, we may need to set a default Content-Type
 	contentType := h.ContentType()
-	if !h.ignoreBody() {
-		if len(contentType) == 0 {
-			contentType = strPostArgsContentType
-		}
-		dst = appendHeaderLine(dst, strContentType, contentType)
-
-		if len(h.contentLengthBytes) > 0 {
-			dst = appendHeaderLine(dst, strContentLength, h.contentLengthBytes)
-		}
-	} else if len(contentType) > 0 {
+	if len(contentType) > 0 {
 		dst = appendHeaderLine(dst, strContentType, contentType)
 	}
+	if len(h.contentLengthBytes) > 0 {
+		dst = appendHeaderLine(dst, strContentLength, h.contentLengthBytes)
+	}
 
 	for i, n := 0, len(h.h); i < n; i++ {
 		kv := &h.h[i]

http.go

@@ -1136,20 +1136,18 @@ func (req *Request) Write(w *bufio.Writer) error {
 		req.Header.SetMultipartFormBoundary(req.multipartFormBoundary)
 	}
 
-	hasBody := !req.Header.ignoreBody()
+	if len(body) == 0 && !req.Header.ignoreBody() {
+		body = req.postArgs.QueryString()
+	}
+	hasBody := len(body) > 0
 	if hasBody {
-		if len(body) == 0 {
-			body = req.postArgs.QueryString()
-		}
 		req.Header.SetContentLength(len(body))
 	}
 	if err = req.Header.Write(w); err != nil {
 		return err
 	}
 	if hasBody {
 		_, err = w.Write(body)
-	} else if len(body) > 0 {
-		return fmt.Errorf("non-zero body for non-POST request. body=%q", body)
 	}
 	return err
 }

http_test.go

@@ -1499,9 +1499,6 @@ func testResponseSuccess(t *testing.T, statusCode int, contentType, serverName,
 func TestRequestWriteError(t *testing.T) {
 	// no host
 	testRequestWriteError(t, "", "/foo/bar", "", "", "")
-
-	// get with body
-	testRequestWriteError(t, "GET", "/foo/bar", "aaa.com", "", "foobar")
 }
 
 func testRequestWriteError(t *testing.T, method, requestURI, host, userAgent, body string) {