fixing sub path_mode

.gitignore

@@ -1,4 +1,5 @@
 compose.yml
 go-proxy.yml
 bin/go-proxy.bak
-logs/
+logs/
+log/

Makefile

@@ -13,14 +13,14 @@ quick-restart: # quick restart without restarting the container
 	docker cp bin/go-proxy go-proxy:/app/go-proxy
 	docker cp templates/* go-proxy:/app/templates
 	docker cp entrypoint.sh go-proxy:/app/entrypoint.sh
-	docker exec -d go-proxy bash -c "/app/entrypoint.sh restart"
+	docker exec -d go-proxy bash /app/entrypoint.sh restart
 
 restart:
 	docker kill go-proxy
 	docker compose up -d go-proxy
 
 logs:
-	docker logs -f go-proxy
+	tail -f log/go-proxy.log
 
 get:
 	go get -d -u ./src/go-proxy

README.md

@@ -25,7 +25,7 @@ In the examples domain `x.y.z` is used, replace them with your domain
 - subdomain matching **(domain name doesn't matter)**
 - path matching
 - HTTP proxy
-- TCP/UDP Proxy (experimental, unable to release port on hot-reload)
+- TCP/UDP Proxy
 - HTTP round robin load balance support (same subdomain and path across containers replicas)
 - Auto hot-reload when container start / die / stop.
 - Simple panel to see all reverse proxies and health (visit port [panel port] of go-proxy `https://*.y.z:[panel port]`)
@@ -97,7 +97,8 @@ However, there are some labels you can manipulate with:
     - forward: path remain unchanged
       1. apps.y.z/webdav -> webdav:80/webdav
       2. apps.y.z./webdav/path/to/file -> webdav:80/webdav/path/to/file
-    - sub: remove path prefix from both URL and HTML attributes (`src`, `href` and `action`)
+    - sub: (experimental) remove path prefix from URL and also append path to HTML link attributes (`src`, `href` and `action`) and Javascript `fetch(url)` by response body substitution
+      e.g. apps.y.z/app1 -> webdav:80, `href="/path/to/file"` -> `href="/app1/path/to/file"`
 
 - `proxy.<alias>.load_balance`: enable load balance
   - allowed: `1`, `true`

compose.example.yml

@@ -19,7 +19,7 @@ services:
     volumes:
       - /path/to/cert.pem:/certs/cert.crt:ro
       - /path/to/privkey.pem:/certs/priv.key:ro
-      - ./go-proxy/logs:/app/log # path to logs
+      - ./log:/app/log # path to logs
       - /var/run/docker.sock:/var/run/docker.sock:ro
     extra_hosts:
       - host.docker.internal:host-gateway # required if you have containers in `host` network_mode

entrypoint.sh

@@ -1,12 +1,15 @@
 #!/bin/bash
 if [ "$1" == "restart" ]; then
+    echo "restarting"
     killall go-proxy
 fi
+if [ -z "$VERBOSITY" ]; then
+    VERBOSITY=1
+fi
+echo "starting with verbosity $VERBOSITY" > log/go-proxy.log
 if [ "$DEBUG" == "1" ]; then
-    /app/go-proxy -v=$VERBOSITY -log_dir=log --stderrthreshold=0 &
-    if [ "$1" != "restart" ]; then
-        tail -f /dev/null
-    fi
+    /app/go-proxy -v=$VERBOSITY -log_dir=log --stderrthreshold=0 2>> log/go-proxy.log &
+    tail -f /dev/null
 else
-    /app/go-proxy -v=$VERBOSITY -log_dir=log --stderrthreshold=0 &
+    /app/go-proxy -v=$VERBOSITY -log_dir=log --stderrthreshold=0
 fi

go.sum

@@ -74,16 +74,12 @@ golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8U
 golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/mod v0.2.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.3.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
-golang.org/x/mod v0.15.0 h1:SernR4v+D55NyBH2QiEQrlBAnj1ECL6AGrA5+dPaMY8=
-golang.org/x/mod v0.15.0/go.mod h1:hTbmBsO62+eylJbnUtE2MGJUyE7QWk4xUqPFrRgJ+7c=
 golang.org/x/mod v0.16.0 h1:QX4fJ0Rr5cPQCF7O9lh9Se4pmwfwskqZfq5moyldzic=
 golang.org/x/mod v0.16.0/go.mod h1:hTbmBsO62+eylJbnUtE2MGJUyE7QWk4xUqPFrRgJ+7c=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20200226121028-0de0cce0169b/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20201021035429-f5854403a974/go.mod h1:sp8m0HH+o8qH0wwXwYZr8TS3Oi6o0r6Gce1SSxlDquU=
-golang.org/x/net v0.21.0 h1:AQyQV4dYCvJ7vGmJyKki9+PBdyvhkSd8EIx/qb0AYv4=
-golang.org/x/net v0.21.0/go.mod h1:bIjVDfnllIU7BJ2DNgfnXvpSvtn8VRwhlsaeUTyUS44=
 golang.org/x/net v0.22.0 h1:9sGLhx7iRIHEiX0oAJ3MRZMUCElJgy7Br1nO+AMN3Tc=
 golang.org/x/net v0.22.0/go.mod h1:JKghWKKOSdJwpW2GEx0Ja7fmaKnMsbu+MWVZTokSYmg=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
@@ -94,8 +90,6 @@ golang.org/x/sync v0.6.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200930185726-fdedc70b468f/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.17.0 h1:25cE3gD+tdBA7lp7QfhuV+rJiE9YXTcS3VG1SqssI/Y=
-golang.org/x/sys v0.17.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/sys v0.18.0 h1:DBdB3niSjOA/O0blCZBqDefyWNYveAYMNF1Wum0DYQ4=
 golang.org/x/sys v0.18.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
@@ -108,8 +102,6 @@ golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGm
 golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.0.0-20200619180055-7c47624df98f/go.mod h1:EkVYQZoAsY45+roYkvgYkIh4xh/qjgUK9TdY2XT94GE=
 golang.org/x/tools v0.0.0-20210106214847-113979e3529a/go.mod h1:emZCQorbCU4vsT4fOWvOPXz4eW1wZW4PmDk9uLelYpA=
-golang.org/x/tools v0.18.0 h1:k8NLag8AGHnn+PHbl7g43CtqZAwG60vZkLqgyZgIHgQ=
-golang.org/x/tools v0.18.0/go.mod h1:GL7B4CwcLLeo59yx/9UWWuNOW1n3VZ4f5axWfML7Lcg=
 golang.org/x/tools v0.19.0 h1:tfGCXNR1OsFG+sVdLAitlpjAvD/I6dHDKnYrpEZUHkw=
 golang.org/x/tools v0.19.0/go.mod h1:qoJWxmGSIBmAeriMx19ogtrEPrGtDbPK634QFIcLAhc=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=

src/go-proxy/constants.go

@@ -46,7 +46,7 @@ const (
 
 const (
 	ProxyPathMode_Forward     = "forward"
-	ProxyPathMode_Sub         = "sub" // TODO: implement
+	ProxyPathMode_Sub         = "sub"
 	ProxyPathMode_RemovedPath = ""
 )
 

src/go-proxy/http_route.go

@@ -65,20 +65,31 @@ func NewHTTPRoute(config *ProxyConfig) (*HTTPRoute, error) {
 			initRewrite(pr)
 			// disable compression
 			pr.Out.Header.Set("Accept-Encoding", "identity")
+			// remove path prefix
 			pr.Out.URL.Path = strings.TrimPrefix(pr.Out.URL.Path, config.Path)
 		}
 		route.Proxy.ModifyResponse = func(r *http.Response) error {
 			contentType, ok := r.Header["Content-Type"]
 			if !ok || len(contentType) == 0 {
-				glog.Infof("unknown content type for %s", r.Request.URL.String())
+				if glog.V(3) {
+					glog.Infof("[Path sub] unknown content type for %s", r.Request.URL.String())
+				}
 				return nil
 			}
-			if !strings.HasPrefix(contentType[0], "text/html") {
-				return nil
+			// disable cache
+			r.Header.Set("Cache-Control", "no-store")
+			
+			var err error = nil
+			switch {
+			case strings.HasPrefix(contentType[0], "text/html"):
+				err = utils.respHTMLSubPath(r, config.Path)
+			case strings.HasPrefix(contentType[0], "application/javascript"):
+				err = utils.respJSSubPath(r, config.Path)
+			default:
+				glog.V(4).Infof("[Path sub] unknown content type(s): %s", contentType)
 			}
-			err := utils.respRemovePath(r, config.Path)
 			if err != nil {
-				err = fmt.Errorf("failed to remove path prefix %s: %v", config.Path, err)
+				err = fmt.Errorf("[Path sub] failed to remove path prefix %s: %v", config.Path, err)
 				r.Status = err.Error()
 				r.StatusCode = http.StatusInternalServerError
 			}
@@ -96,7 +107,7 @@ func NewHTTPRoute(config *ProxyConfig) (*HTTPRoute, error) {
 			rewrite(pr)
 			r := pr.In
 			glog.Infof("[Request] %s %s%s", r.Method, r.Host, r.URL.Path)
-			glog.V(4).InfoDepthf(1, "Headers: %v", r.Header)
+			glog.V(5).InfoDepthf(1, "Headers: %v", r.Header)
 		}
 	} else {
 		route.Proxy.Rewrite = rewrite
@@ -141,7 +152,6 @@ func httpProxyHandler(w http.ResponseWriter, r *http.Request) {
 			r.URL.Path,
 			err,
 		)
-		glog.Error(err)
 		http.Error(w, err.Error(), http.StatusNotFound)
 		return
 	}

src/go-proxy/main.go

@@ -4,6 +4,7 @@ import (
 	"flag"
 	"net/http"
 	"runtime"
+	"time"
 
 	"github.com/docker/docker/api/types"
 	"github.com/docker/docker/api/types/filters"
@@ -51,6 +52,12 @@ func main() {
 		}
 	}()
 
+	go func() {
+		for range time.Tick(100 * time.Millisecond) {
+			glog.Flush()
+		}
+	}()
+
 	mux := http.NewServeMux()
 	mux.HandleFunc("/", httpProxyHandler)
 

src/go-proxy/utils.go

@@ -6,10 +6,14 @@ import (
 	"io"
 	"net"
 	"net/http"
+	"path"
+	"path/filepath"
+	"regexp"
 	"strings"
 	"sync"
 	"time"
 
+	"github.com/golang/glog"
 	xhtml "golang.org/x/net/html"
 )
 
@@ -79,7 +83,7 @@ func (*Utils) healthCheckHttp(targetUrl string) error {
 	return err
 }
 
-func (*Utils) healthCheckStream(scheme string, host string) error {
+func (*Utils) healthCheckStream(scheme, host string) error {
 	conn, err := net.DialTimeout(scheme, host, 5*time.Second)
 	if err != nil {
 		return err
@@ -93,25 +97,49 @@ func (*Utils) snakeToCamel(s string) string {
 	return strings.ReplaceAll(toHyphenCamel, "-", "")
 }
 
-func htmlNodesSubPath(node *xhtml.Node, path string) {
-	if node.Type == xhtml.ElementNode {
-		for _, attr := range node.Attr {
-			switch attr.Key {
-			case "src": // img, script, etc.
-			case "href": // link
-			case "action": // form
-				if strings.HasPrefix(attr.Val, path) {
-					attr.Val = strings.Replace(attr.Val, path, "", 1)
-				}
-			}
-		}
-	}
-	for c := node.FirstChild; c != nil; c = c.NextSibling {
-		htmlNodesSubPath(c, path)
+func tryAppendPathPrefixImpl(pOrig, pAppend string) string {
+	switch {
+	case strings.Contains(pOrig, "://"):
+		return pOrig
+	case pOrig == "", pOrig == "#", pOrig == "/":
+		return pAppend
+	case filepath.IsLocal(pOrig) && !strings.HasPrefix(pOrig, pAppend):
+		return path.Join(pAppend, pOrig)
+	default:
+		return pOrig
 	}
 }
 
-func (*Utils) respRemovePath(r *http.Response, path string) error {
+var tryAppendPathPrefix func(string, string) string
+var _ = func() int {
+	if glog.V(4) {
+		tryAppendPathPrefix = func(s1, s2 string) string {
+			replaced := tryAppendPathPrefixImpl(s1, s2)
+			glog.Infof("[Path sub] %s -> %s", s1, replaced)
+			return replaced
+		}
+	} else {
+		tryAppendPathPrefix = tryAppendPathPrefixImpl
+	}
+	return 1
+}()
+
+func htmlNodesSubPath(n *xhtml.Node, p string) {
+	if n.Type == xhtml.ElementNode {
+		for i, attr := range n.Attr {
+			switch attr.Key {
+			case "src", "href", "action": // img, script, link, form etc.
+				n.Attr[i].Val = tryAppendPathPrefix(attr.Val, p)
+			}
+		}
+	}
+
+	for c := n.FirstChild; c != nil; c = c.NextSibling {
+		htmlNodesSubPath(c, p)
+	}
+}
+
+func (*Utils) respHTMLSubPath(r *http.Response, p string) error {
 	// remove all path prefix from relative path in script, img, a, ...
 	doc, err := xhtml.Parse(r.Body)
 
@@ -119,11 +147,14 @@ func (*Utils) respRemovePath(r *http.Response, path string) error {
 		return err
 	}
 
-	htmlNodesSubPath(doc, path)
+	if p[0] == '/' {
+		p = p[1:]
+	}
+	htmlNodesSubPath(doc, p)
 
 	var buf bytes.Buffer
 	err = xhtml.Render(&buf, doc)
-	
+
 	if err != nil {
 		return err
 	}
@@ -132,3 +163,29 @@ func (*Utils) respRemovePath(r *http.Response, path string) error {
 
 	return nil
 }
+
+func (*Utils) respJSSubPath(r *http.Response, p string) error {
+	var buf bytes.Buffer
+
+	_, err := buf.ReadFrom(r.Body)
+	if err != nil {
+		return err
+	}
+
+	if p[0] == '/' {
+		p = p[1:]
+	}
+
+	js := buf.String()
+
+	re := regexp.MustCompile(`fetch\(["'].+["']\)`)
+	replace := func(match string) string {
+		match = match[7 : len(match)-2]
+		replaced := tryAppendPathPrefix(match, p)
+		return fmt.Sprintf(`fetch(%q)`, replaced)
+	}
+	js = re.ReplaceAllStringFunc(js, replace)
+
+	r.Body = io.NopCloser(strings.NewReader(js))
+	return nil
+}

templates/panel.html

@@ -72,8 +72,8 @@
         function updateHealthStatus() {
             let rows = document.querySelectorAll('tbody tr');
             rows.forEach(row => {
-                let url = row.cells[2].textContent;
-                let cell = row.cells[3]; // Health column cell
+                let url = row.cells[3].textContent;
+                let cell = row.cells[4]; // Health column cell
                 checkHealth(url, cell);
             });
         }
@@ -100,6 +100,7 @@
                         <tr>
                             <th>Alias</th>
                             <th>Path</th>
+                            <th>Path Mode</th>
                             <th>URL</th>
                             <th>Health</th>
                         </tr>
@@ -111,6 +112,7 @@
                         <tr>
                             <td>{{$alias}}</td>
                             <td>{{$path}}</td>
+                            <td>{{$route.PathMode}}</td>
                             <td>{{$route.Url.String}}</td>
                             <td class="align-middle">
                                 <div class="health-circle"></div>