Closed
Description
The ReverseProxy.ServeHTTP
performs a shallow copy of the incoming request. This includes just copying the pointer of req.URL
to outreq.URL
. The director
is likely to mutate that request URL, which can lead to mismatched pre/post logging.
Workaround: Copy the url.URL
within a custom director.
What version of Go are you using (go version
)?
go version go1.8.1 darwin/amd64
What operating system and processor architecture are you using (go env
)?
GOARCH="amd64"
GOBIN=""
GOEXE=""
GOHOSTARCH="amd64"
GOHOSTOS="darwin"
GOOS="darwin"
GOPATH="/Users/aron/go"
GORACE=""
GOROOT="/usr/local/go"
GOTOOLDIR="/usr/local/go/pkg/tool/darwin_amd64"
GCCGO="gccgo"
CC="clang"
GOGCCFLAGS="-fPIC -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=/var/folders/ts/s940qvdj5vj1czr9qh07fvtw0000gn/T/go-build348823784=/tmp/go-build -gno-record-gcc-switches -fno-common"
CXX="clang++"
CGO_ENABLED="1"
PKG_CONFIG="pkg-config"
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
What did you do?
package main
import (
"log"
"net/http"
"net/http/httputil"
"net/url"
)
func main() {
target, err := url.Parse("http://google.com/")
if err != nil {
log.Fatalf("could not parse URL: %s", err)
}
pxy := httputil.NewSingleHostReverseProxy(target)
server := http.Server{
Addr: ":9999",
Handler: http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
log.Printf("proxy starting: %s", r.URL)
pxy.ServeHTTP(w, r)
log.Printf("proxy complete: %s", r.URL)
}),
}
err = server.ListenAndServe()
if err != nil {
log.Fatalf("could not serve: %s", err)
}
}
$ curl http://localhost:9999/ > /dev/null
What did you expect to see?
2017/04/21 11:14:54 proxy starting: /
2017/04/21 11:14:54 proxy complete: /
What did you see instead?
2017/04/21 11:14:54 proxy starting: /
2017/04/21 11:14:54 proxy complete: http://google.com/