refactoring: moved reverse_proxy to separate package to avoid import cycle

internal/docker/idlewatcher/waker.go

@@ -8,7 +8,7 @@ import (
 	"github.com/yusing/go-proxy/internal/docker/idlewatcher/types"
 	E "github.com/yusing/go-proxy/internal/error"
 	"github.com/yusing/go-proxy/internal/metrics"
-	gphttp "github.com/yusing/go-proxy/internal/net/http"
+	"github.com/yusing/go-proxy/internal/net/http/reverseproxy"
 	net "github.com/yusing/go-proxy/internal/net/types"
 	route "github.com/yusing/go-proxy/internal/route/types"
 	"github.com/yusing/go-proxy/internal/task"
@@ -22,7 +22,7 @@ type (
 	waker struct {
 		_ U.NoCopy
 
-		rp     *gphttp.ReverseProxy
+		rp     *reverseproxy.ReverseProxy
 		stream net.Stream
 		hc     health.HealthChecker
 		metric *metrics.Gauge
@@ -38,7 +38,7 @@ const (
 
 // TODO: support stream
 
-func newWaker(parent task.Parent, entry route.Entry, rp *gphttp.ReverseProxy, stream net.Stream) (Waker, E.Error) {
+func newWaker(parent task.Parent, entry route.Entry, rp *reverseproxy.ReverseProxy, stream net.Stream) (Waker, E.Error) {
 	hcCfg := entry.RawEntry().HealthCheck
 	hcCfg.Timeout = idleWakerCheckTimeout
 
@@ -71,7 +71,7 @@ func newWaker(parent task.Parent, entry route.Entry, rp *gphttp.ReverseProxy, st
 }
 
 // lifetime should follow route provider.
-func NewHTTPWaker(parent task.Parent, entry route.Entry, rp *gphttp.ReverseProxy) (Waker, E.Error) {
+func NewHTTPWaker(parent task.Parent, entry route.Entry, rp *reverseproxy.ReverseProxy) (Waker, E.Error) {
 	return newWaker(parent, entry, rp, nil)
 }
 

internal/net/http/header_utils.go

@@ -2,6 +2,10 @@ package http
 
 import (
 	"net/http"
+	"net/textproto"
+
+	"github.com/yusing/go-proxy/internal/utils/strutils"
+	"golang.org/x/net/http/httpguts"
 )
 
 const (
@@ -22,6 +26,48 @@ const (
 	HeaderContentLength = "Content-Length"
 )
 
+// Hop-by-hop headers. These are removed when sent to the backend.
+// As of RFC 7230, hop-by-hop headers are required to appear in the
+// Connection header field. These are the headers defined by the
+// obsoleted RFC 2616 (section 13.5.1) and are used for backward
+// compatibility.
+var hopHeaders = []string{
+	"Connection",
+	"Proxy-Connection", // non-standard but still sent by libcurl and rejected by e.g. google
+	"Keep-Alive",
+	"Proxy-Authenticate",
+	"Proxy-Authorization",
+	"Te",      // canonicalized version of "TE"
+	"Trailer", // not Trailers per URL above; https://www.rfc-editor.org/errata_search.php?eid=4522
+	"Transfer-Encoding",
+	"Upgrade",
+}
+
+func UpgradeType(h http.Header) string {
+	if !httpguts.HeaderValuesContainsToken(h["Connection"], "Upgrade") {
+		return ""
+	}
+	return h.Get("Upgrade")
+}
+
+// RemoveHopByHopHeaders removes hop-by-hop headers.
+func RemoveHopByHopHeaders(h http.Header) {
+	// RFC 7230, section 6.1: Remove headers listed in the "Connection" header.
+	for _, f := range h["Connection"] {
+		for _, sf := range strutils.SplitComma(f) {
+			if sf = textproto.TrimString(sf); sf != "" {
+				h.Del(sf)
+			}
+		}
+	}
+	// RFC 2616, section 13.5.1: Remove a set of known hop-by-hop headers.
+	// This behavior is superseded by the RFC 7230 Connection header, but
+	// preserve it for backwards compatibility.
+	for _, f := range hopHeaders {
+		h.Del(f)
+	}
+}
+
 func RemoveHop(h http.Header) {
 	reqUpType := UpgradeType(h)
 	RemoveHopByHopHeaders(h)

internal/net/http/logger.go

@@ -1,5 +0,0 @@
-package http
-
-import "github.com/yusing/go-proxy/internal/logging"
-
-var logger = logging.With().Str("module", "http").Logger()

internal/net/http/middleware/middleware.go

@@ -9,14 +9,15 @@ import (
 	E "github.com/yusing/go-proxy/internal/error"
 	"github.com/yusing/go-proxy/internal/logging"
 	gphttp "github.com/yusing/go-proxy/internal/net/http"
+	"github.com/yusing/go-proxy/internal/net/http/reverseproxy"
 	"github.com/yusing/go-proxy/internal/utils"
 )
 
 type (
 	Error = E.Error
 
-	ReverseProxy = gphttp.ReverseProxy
+	ReverseProxy = reverseproxy.ReverseProxy
-	ProxyRequest = gphttp.ProxyRequest
+	ProxyRequest = reverseproxy.ProxyRequest
 
 	ImplNewFunc = func() any
 	OptionsRaw  = map[string]any

internal/net/http/middleware/set_upstream_headers.go

@@ -4,6 +4,7 @@ import (
 	"net/http"
 
 	gphttp "github.com/yusing/go-proxy/internal/net/http"
+	"github.com/yusing/go-proxy/internal/net/http/reverseproxy"
 )
 
 // internal use only.
@@ -13,7 +14,7 @@ type setUpstreamHeaders struct {
 
 var suh = NewMiddleware[setUpstreamHeaders]()
 
-func newSetUpstreamHeaders(rp *gphttp.ReverseProxy) *Middleware {
+func newSetUpstreamHeaders(rp *reverseproxy.ReverseProxy) *Middleware {
 	m, err := suh.New(OptionsRaw{
 		"name":   rp.TargetName,
 		"scheme": rp.TargetURL.Scheme,

internal/net/http/middleware/test_utils.go

@@ -10,7 +10,7 @@ import (
 
 	"github.com/yusing/go-proxy/internal/common"
 	E "github.com/yusing/go-proxy/internal/error"
-	gphttp "github.com/yusing/go-proxy/internal/net/http"
+	"github.com/yusing/go-proxy/internal/net/http/reverseproxy"
 	"github.com/yusing/go-proxy/internal/net/types"
 )
 
@@ -139,7 +139,7 @@ func newMiddlewareTest(middleware *Middleware, args *testArgs) (*TestResult, E.E
 		rr.parent = http.DefaultTransport
 	}
 
-	rp := gphttp.NewReverseProxy(middleware.name, args.upstreamURL, rr)
+	rp := reverseproxy.NewReverseProxy(middleware.name, args.upstreamURL, rr)
 
 	mid, setOptErr := middleware.New(args.middlewareOpt)
 	if setOptErr != nil {

internal/net/http/reverseproxy/reverse_proxy_mod.go

@@ -2,7 +2,7 @@
 // Modified from the Go project under the a BSD-style License (https://cs.opensource.google/go/go/+/refs/tags/go1.23.1:src/net/http/httputil/reverseproxy.go)
 // https://cs.opensource.google/go/go/+/master:LICENSE
 
-package http
+package reverseproxy
 
 // This is a small mod on net/http/httputil/reverseproxy.go
 // that boosts performance in some cases
@@ -26,11 +26,12 @@ import (
 
 	"github.com/rs/zerolog"
 	"github.com/yusing/go-proxy/internal/common"
+	"github.com/yusing/go-proxy/internal/logging"
 	"github.com/yusing/go-proxy/internal/metrics"
+	gphttp "github.com/yusing/go-proxy/internal/net/http"
 	"github.com/yusing/go-proxy/internal/net/http/accesslog"
 	"github.com/yusing/go-proxy/internal/net/types"
 	U "github.com/yusing/go-proxy/internal/utils"
-	"github.com/yusing/go-proxy/internal/utils/strutils"
 	"golang.org/x/net/http/httpguts"
 )
 
@@ -77,7 +78,6 @@ type ReverseProxy struct {
 	zerolog.Logger
 
 	// The transport used to perform proxy requests.
-	// If nil, http.DefaultTransport is used.
 	Transport http.RoundTripper
 
 	// ModifyResponse is an optional function that modifies the
@@ -104,6 +104,8 @@ type httpMetricLogger struct {
 	labels    *metrics.HTTPRouteMetricLabels
 }
 
+var logger = logging.With().Str("module", "reverse_proxy").Logger()
+
 // WriteHeader implements http.ResponseWriter.
 func (l *httpMetricLogger) WriteHeader(status int) {
 	l.ResponseWriter.WriteHeader(status)
@@ -222,23 +224,6 @@ func copyHeader(dst, src http.Header) {
 	}
 }
 
-// Hop-by-hop headers. These are removed when sent to the backend.
-// As of RFC 7230, hop-by-hop headers are required to appear in the
-// Connection header field. These are the headers defined by the
-// obsoleted RFC 2616 (section 13.5.1) and are used for backward
-// compatibility.
-var hopHeaders = []string{
-	"Connection",
-	"Proxy-Connection", // non-standard but still sent by libcurl and rejected by e.g. google
-	"Keep-Alive",
-	"Proxy-Authenticate",
-	"Proxy-Authorization",
-	"Te",      // canonicalized version of "TE"
-	"Trailer", // not Trailers per URL above; https://www.rfc-editor.org/errata_search.php?eid=4522
-	"Transfer-Encoding",
-	"Upgrade",
-}
-
 func (p *ReverseProxy) errorHandler(rw http.ResponseWriter, r *http.Request, err error, writeHeader bool) {
 	switch {
 	case errors.Is(err, context.Canceled),
@@ -348,14 +333,14 @@ func (p *ReverseProxy) handler(rw http.ResponseWriter, req *http.Request) {
 	p.rewriteRequestURL(outreq)
 	outreq.Close = false
 
-	reqUpType := UpgradeType(outreq.Header)
+	reqUpType := gphttp.UpgradeType(outreq.Header)
 	if !IsPrint(reqUpType) {
 		p.errorHandler(rw, req, fmt.Errorf("client tried to switch to invalid protocol %q", reqUpType), true)
 		return
 	}
 
 	req.Header.Del("Forwarded")
-	RemoveHopByHopHeaders(outreq.Header)
+	gphttp.RemoveHopByHopHeaders(outreq.Header)
 
 	// Issue 21096: tell backend applications that care about trailer support
 	// that we support trailers. (We do, but we don't go out of our way to
@@ -380,14 +365,14 @@ func (p *ReverseProxy) handler(rw http.ResponseWriter, req *http.Request) {
 	// 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.
-	prior, ok := outreq.Header[HeaderXForwardedFor]
+	prior, ok := outreq.Header[gphttp.HeaderXForwardedFor]
 	omit := ok && prior == nil // Issue 38079: nil now means don't populate the header
 	xff := visitorIP
 	if len(prior) > 0 {
 		xff = strings.Join(prior, ", ") + ", " + xff
 	}
 	if !omit {
-		outreq.Header.Set(HeaderXForwardedFor, xff)
+		outreq.Header.Set(gphttp.HeaderXForwardedFor, xff)
 	}
 
 	var reqScheme string
@@ -397,10 +382,10 @@ func (p *ReverseProxy) handler(rw http.ResponseWriter, req *http.Request) {
 		reqScheme = "http"
 	}
 
-	outreq.Header.Set(HeaderXForwardedMethod, req.Method)
+	outreq.Header.Set(gphttp.HeaderXForwardedMethod, req.Method)
-	outreq.Header.Set(HeaderXForwardedProto, reqScheme)
+	outreq.Header.Set(gphttp.HeaderXForwardedProto, reqScheme)
-	outreq.Header.Set(HeaderXForwardedHost, req.Host)
+	outreq.Header.Set(gphttp.HeaderXForwardedHost, req.Host)
-	outreq.Header.Set(HeaderXForwardedURI, req.RequestURI)
+	outreq.Header.Set(gphttp.HeaderXForwardedURI, req.RequestURI)
 
 	if _, ok := outreq.Header["User-Agent"]; !ok {
 		// If the outbound request doesn't have a User-Agent header set,
@@ -467,7 +452,7 @@ func (p *ReverseProxy) handler(rw http.ResponseWriter, req *http.Request) {
 		return
 	}
 
-	RemoveHopByHopHeaders(res.Header)
+	gphttp.RemoveHopByHopHeaders(res.Header)
 
 	if !p.modifyResponse(rw, res, req, outreq) {
 		return
@@ -518,31 +503,6 @@ func (p *ReverseProxy) handler(rw http.ResponseWriter, req *http.Request) {
 	}
 }
 
-func UpgradeType(h http.Header) string {
-	if !httpguts.HeaderValuesContainsToken(h["Connection"], "Upgrade") {
-		return ""
-	}
-	return h.Get("Upgrade")
-}
-
-// RemoveHopByHopHeaders removes hop-by-hop headers.
-func RemoveHopByHopHeaders(h http.Header) {
-	// RFC 7230, section 6.1: Remove headers listed in the "Connection" header.
-	for _, f := range h["Connection"] {
-		for _, sf := range strutils.SplitComma(f) {
-			if sf = textproto.TrimString(sf); sf != "" {
-				h.Del(sf)
-			}
-		}
-	}
-	// RFC 2616, section 13.5.1: Remove a set of known hop-by-hop headers.
-	// This behavior is superseded by the RFC 7230 Connection header, but
-	// preserve it for backwards compatibility.
-	for _, f := range hopHeaders {
-		h.Del(f)
-	}
-}
-
 // reference: https://github.com/traefik/traefik/blob/master/pkg/proxy/httputil/proxy.go
 // https://tools.ietf.org/html/rfc6455#page-20
 func cleanWebsocketHeaders(req *http.Request) {
@@ -563,8 +523,8 @@ func cleanWebsocketHeaders(req *http.Request) {
 }
 
 func (p *ReverseProxy) handleUpgradeResponse(rw http.ResponseWriter, req *http.Request, res *http.Response) {
-	reqUpType := UpgradeType(req.Header)
+	reqUpType := gphttp.UpgradeType(req.Header)
-	resUpType := UpgradeType(res.Header)
+	resUpType := gphttp.UpgradeType(res.Header)
 	if !IsPrint(resUpType) { // We know reqUpType is ASCII, it's checked by the caller.
 		p.errorHandler(rw, req, fmt.Errorf("backend tried to switch to invalid protocol %q", resUpType), true)
 		return

internal/route/http.go

@@ -13,6 +13,7 @@ import (
 	"github.com/yusing/go-proxy/internal/net/http/loadbalancer"
 	loadbalance "github.com/yusing/go-proxy/internal/net/http/loadbalancer/types"
 	"github.com/yusing/go-proxy/internal/net/http/middleware"
+	"github.com/yusing/go-proxy/internal/net/http/reverseproxy"
 	"github.com/yusing/go-proxy/internal/route/entry"
 	"github.com/yusing/go-proxy/internal/route/routes"
 	route "github.com/yusing/go-proxy/internal/route/types"
@@ -30,7 +31,7 @@ type (
 		loadBalancer *loadbalancer.LoadBalancer
 		server       *loadbalancer.Server
 		handler      http.Handler
-		rp           *gphttp.ReverseProxy
+		rp           *reverseproxy.ReverseProxy
 
 		task *task.Task
 
@@ -49,7 +50,7 @@ func NewHTTPRoute(entry *entry.ReverseProxyEntry) (impl, E.Error) {
 	}
 
 	service := entry.TargetName()
-	rp := gphttp.NewReverseProxy(service, entry.URL, trans)
+	rp := reverseproxy.NewReverseProxy(service, entry.URL, trans)
 
 	if len(entry.Raw.Middlewares) > 0 {
 		err := middleware.PatchReverseProxy(rp, entry.Raw.Middlewares)