commit a4427ae4f5907a8afc538f4403bf475148b273dc Author: David Fifield david@bamsoftware.com Date: Thu Sep 25 02:01:12 2014 -0700
Reuse the same RoundTripper for all requests.
Previously we were creating a new http.Transport for each request, and selectively overriding the Proxy member. Since that code was first added, http.DefaultTransport has gotten other non-zero settings than Proxy: Dial and TLSHandshakeTimeout.
https://code.google.com/p/go/source/diff?spec=svn733fefb1deae5490f2d6fcf4986... https://code.google.com/p/go/source/diff?spec=svnc8edfe4ddd5a28d929503ac34d3...
We want to use those settings, but we also want to disable the default ProxyFromEnvironment. Creating a new Transport every time was messing with persistent connections; I watched as meek-client made a new TCP connection for every request. With this change, it reuses the same connection. Something must have changed in the http library (perhaps one of the revisions cited above), because I remember it using a persistent connection in the past.
This only makes a difference when not using --helper. The browser helper handles all its own persistence stuff. --- meek-client/meek-client.go | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-)
diff --git a/meek-client/meek-client.go b/meek-client/meek-client.go index d39e06a..33861e5 100644 --- a/meek-client/meek-client.go +++ b/meek-client/meek-client.go @@ -82,6 +82,10 @@ const (
var ptInfo pt.ClientInfo
+// This is the RoundTripper used to make all our requests (when --helper is not +// used). +var httpTransport http.Transport + // Store for command line options. var options struct { URL string @@ -110,13 +114,6 @@ 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) { - tr := new(http.Transport) - if options.ProxyURL != nil { - if options.ProxyURL.Scheme != "http" { - panic(fmt.Sprintf("don't know how to use proxy %s", options.ProxyURL.String())) - } - tr.Proxy = http.ProxyURL(options.ProxyURL) - } req, err := http.NewRequest("POST", info.URL.String(), bytes.NewReader(buf)) if err != nil { return nil, err @@ -125,7 +122,7 @@ func roundTripWithHTTP(buf []byte, info *RequestInfo) (*http.Response, error) { req.Host = info.Host } req.Header.Set("X-Session-Id", info.SessionID) - return tr.RoundTrip(req) + return httpTransport.RoundTrip(req) }
// Do a roundtrip, trying at most limit times if there is an HTTP status other @@ -394,6 +391,13 @@ func main() { } }
+ // We make a copy of DefaultTransport because we want the default Dial + // and TLSHandshakeTimeout settings. But we want to disable the default + // ProxyFromEnvironment setting. Proxy is overridden below if proxyURL + // is set. + httpTransport = *http.DefaultTransport.(*http.Transport) + httpTransport.Proxy = nil + ptInfo, err = pt.ClientSetup([]string{ptMethodName}) if err != nil { log.Fatalf("error in ClientSetup: %s", err) @@ -416,6 +420,7 @@ func main() { log.Fatal(fmt.Sprintf("proxy error: %s", err)) } log.Printf("using proxy %s", options.ProxyURL.String()) + httpTransport.Proxy = http.ProxyURL(options.ProxyURL) if ptProxyURL != nil { PtProxyDone() }