func (s *httpService) handle(req *http.Request, sc *httputil.ServerConn, tls, sticky bool) {
for {
req.Header.Set("X-Request-Start", strconv.FormatInt(time.Now().UnixNano()/int64(time.Millisecond), 10))
var backend *httputil.ClientConn
var stickyCookie *http.Cookie
if sticky {
backend, stickyCookie = s.getBackendSticky(req)
} else {
backend = s.getBackend()
}
if backend == nil {
log.Println("no backend found")
fail(sc, req, 503, "Service Unavailable")
return
}
if req.Method != "GET" && req.Method != "POST" && req.Method != "HEAD" &&
req.Method != "OPTIONS" && req.Method != "PUT" && req.Method != "DELETE" && req.Method != "TRACE" {
fail(sc, req, 405, "Method not allowed")
return
}
req.Proto = "HTTP/1.1"
req.ProtoMajor = 1
req.ProtoMinor = 1
delete(req.Header, "Te")
delete(req.Header, "Transfer-Encoding")
if clientIP, _, err := net.SplitHostPort(req.RemoteAddr); err == nil {
// If we aren't the first proxy retain prior
// X-Forwarded-For information as a comma+space
// separated list and fold multiple headers into one.
if prior, ok := req.Header["X-Forwarded-For"]; ok {
clientIP = strings.Join(prior, ", ") + ", " + clientIP
}
req.Header.Set("X-Forwarded-For", clientIP)
}
if tls {
req.Header.Set("X-Forwarded-Proto", "https")
} else {
req.Header.Set("X-Forwarded-Proto", "http")
}
// TODO: Set X-Forwarded-Port
if err := backend.Write(req); err != nil {
log.Println("server write err:", err)
return
}
res, err := backend.Read(req)
if res != nil {
if stickyCookie != nil {
res.Header.Add("Set-Cookie", stickyCookie.String())
}
if res.StatusCode == http.StatusSwitchingProtocols {
res.Body = nil
}
if err := sc.Write(req, res); err != nil {
if err != io.EOF && err != httputil.ErrPersistEOF {
log.Println("client write err:", err)
// TODO: log error
}
return
}
}
if err != nil {
if err != io.EOF && err != httputil.ErrPersistEOF {
log.Println("server read err:", err)
// TODO: log error
fail(sc, req, 502, "Bad Gateway")
}
return
}
// TODO: Proxy HTTP CONNECT? (example: Go RPC over HTTP)
if res.StatusCode == http.StatusSwitchingProtocols {
serverW, serverR := backend.Hijack()
clientW, clientR := sc.Hijack()
defer serverW.Close()
done := make(chan struct{})
go func() {
serverR.WriteTo(clientW)
if cw, ok := clientW.(writeCloser); ok {
cw.CloseWrite()
}
close(done)
}()
clientR.WriteTo(serverW)
serverW.(writeCloser).CloseWrite()
<-done
return
}
// close the backend connection, so we don't accidently send to
// a closed socket on the backend
backend.Close()
// TODO: http pipelining
req, err = sc.Read()
if err != nil {
if err != io.EOF && err != httputil.ErrPersistEOF {
log.Println("client read err:", err)
}
return
}
}
}
func (s *httpServer) handle(req *http.Request, sc *httputil.ServerConn, tls bool) {
req.Header.Set("X-Request-Start", strconv.FormatInt(time.Now().UnixNano()/int64(time.Millisecond), 10))
backend := s.getBackend()
if backend == nil {
// TODO: Return 503
log.Println("no backend found")
return
}
defer backend.Close()
for {
if req.Method != "GET" && req.Method != "POST" && req.Method != "HEAD" &&
req.Method != "OPTIONS" && req.Method != "PUT" && req.Method != "DELETE" && req.Method != "TRACE" {
// TODO: return 405
}
req.Proto = "HTTP/1.1"
req.ProtoMajor = 1
req.ProtoMinor = 1
delete(req.Header, "Te")
delete(req.Header, "Transfer-Encoding")
if clientIP, _, err := net.SplitHostPort(req.RemoteAddr); err == nil {
// If we aren't the first proxy retain prior
// X-Forwarded-For information as a comma+space
// separated list and fold multiple headers into one.
if prior, ok := req.Header["X-Forwarded-For"]; ok {
clientIP = strings.Join(prior, ", ") + ", " + clientIP
}
req.Header.Set("X-Forwarded-For", clientIP)
}
if tls {
req.Header.Set("X-Forwarded-Proto", "https")
} else {
req.Header.Set("X-Forwarded-Proto", "http")
}
// TODO: Set X-Forwarded-Port
if err := backend.Write(req); err != nil {
log.Println("server write err:", err)
return
}
res, err := backend.Read(req)
if res != nil {
if err := sc.Write(req, res); err != nil {
if err != io.EOF && err != httputil.ErrPersistEOF {
log.Println("client write err:", err)
// TODO: log error
}
return
}
}
if err != nil {
if err != io.EOF && err != httputil.ErrPersistEOF {
log.Println("server read err:", err)
// TODO: log error
// TODO: Return 502
}
return
}
// TODO: Proxy HTTP CONNECT? (example: Go RPC over HTTP)
if res.StatusCode == http.StatusSwitchingProtocols {
serverW, serverR := backend.Hijack()
clientW, clientR := sc.Hijack()
defer serverW.Close()
done := make(chan struct{})
go func() {
serverR.WriteTo(clientW)
close(done)
}()
clientR.WriteTo(serverW)
<-done
return
}
// TODO: http pipelining
req, err = sc.Read()
if err != nil {
if err != io.EOF && err != httputil.ErrPersistEOF {
log.Println("client read err:", err)
}
return
}
req.Header.Set("X-Request-Start", strconv.FormatInt(time.Now().UnixNano()/int64(time.Millisecond), 10))
}
}