Explicitly set Content-Length to zero when there is no data to send.

Since Go 1.8 http.Transport does not set Content-Length header if body contains no bytes. https://golang.org/doc/go1.8#net_http https://go-review.googlesource.com/c/31445/ However some of domain fronts do inspect Content-Length header and return 411 error when it is not set. This breaks connection entierly since these packets do not travel beyond a frontend to a meek server. Closes #22865.

Explicitly set Content-Length to zero when there is no data to send.
0ea861ef · Ivan Markin · David Fifield · a26d0998 · 0ea861ef
Commit 0ea861ef authored 7 years ago by Ivan Markin Committed by David Fifield 7 years ago
--- a/meek-client/meek-client.go
+++ b/meek-client/meek-client.go
@@ -116,7 +116,11 @@ type RequestInfo struct {
 // Do an HTTP roundtrip using the payload data in buf and the request metadata
 // in info.
 func roundTripWithHTTP(buf []byte, info *RequestInfo) (*http.Response, error) {
-	req, err := http.NewRequest("POST", info.URL.String(), bytes.NewReader(buf))
+	var body io.Reader
+	if len(buf) > 0 {
+		body = bytes.NewReader(buf)
+	}
+	req, err := http.NewRequest("POST", info.URL.String(), body)
 	if err != nil {
 		return nil, err
 	}