updated app build

golangproxy/proxy/proxy.go

@@ -0,0 +1,96 @@
+package proxy
+
+import (
+	"context"
+	"crypto/tls"
+	"net"
+	"net/http"
+	"net/http/httputil"
+	"net/url"
+
+	"golangproxy/logger"
+)
+
+// Route holds proxy configuration for a specific host
+type Route struct {
+	Proxy           *httputil.ReverseProxy // The reverse proxy instance
+	Handler         http.Handler           // Custom handler wrapping the proxy
+	NoHTTPSRedirect bool                   // Disable HTTP to HTTPS redirect
+	Target          string                 // Target URL for proxying
+}
+
+// CreateRoute initializes a reverse proxy for a target with trust settings
+func CreateRoute(target string, trustInvalidCert bool) *Route {
+	url, _ := url.Parse(target)
+	proxy := httputil.NewSingleHostReverseProxy(url)
+	if url.Scheme == "https" {
+		proxy.Transport = &http.Transport{
+			TLSClientConfig: &tls.Config{InsecureSkipVerify: trustInvalidCert},
+		}
+	}
+
+	// Modify the Director based on whether the target is an IP or hostname
+	originalDirector := proxy.Director
+	proxy.Director = func(req *http.Request) {
+		originalDirector(req)
+		if isIPTarget(url.Hostname()) {
+			// For IP targets, preserve the incoming Host header (e.g., main.example.com)
+			// This ensures session cookies match the client's requested domain
+		} else {
+			// For hostname targets, set Host to the target's hostname (e.g., example.com)
+			req.Host = url.Host
+		}
+		req.Header.Set("X-Forwarded-For", req.RemoteAddr)
+		req.Header.Set("X-Forwarded-Host", req.Host)
+		req.Header.Set("X-Forwarded-Proto", url.Scheme)
+		if req.Header.Get("User-Agent") == "" {
+			req.Header.Set("User-Agent", "GoLangProxy")
+		}
+		//logger.Logger.Printf("Proxying to %s - Headers: %v, Cookies: %v", target, req.Header, req.Cookies())
+	}
+
+	// Create a custom handler to wrap the proxy and filter context canceled errors
+	handler := http.HandlerFunc(func(rw http.ResponseWriter, req *http.Request) {
+		rwWrapper := &responseWriterWrapper{ResponseWriter: rw}
+		proxy.ServeHTTP(rwWrapper, req)
+		if err := req.Context().Err(); err != nil && err != context.Canceled {
+			logger.Logger.Printf("Proxy error for %s: %v", target, err)
+		}
+		//logger.Logger.Printf("Response from %s - Headers: %v, Status: %d", target, rwWrapper.Header(), rwWrapper.status)
+	})
+
+	return &Route{
+		Proxy:   proxy,
+		Handler: handler,
+		Target:  target,
+	}
+}
+
+// isIPTarget checks if the target hostname is an IP address
+func isIPTarget(host string) bool {
+	// Split host and port if a port is present (e.g., "10.100.111.254:4444")
+	hostname, _, err := net.SplitHostPort(host)
+	if err != nil {
+		// If there's no port (or an error splitting), use the original host
+		hostname = host
+	}
+	return net.ParseIP(hostname) != nil
+}
+
+// responseWriterWrapper captures response status and headers
+type responseWriterWrapper struct {
+	http.ResponseWriter
+	status int
+}
+
+func (rw *responseWriterWrapper) WriteHeader(status int) {
+	rw.status = status
+	rw.ResponseWriter.WriteHeader(status)
+}
+
+func (rw *responseWriterWrapper) Write(b []byte) (int, error) {
+	if rw.status == 0 {
+		rw.status = http.StatusOK
+	}
+	return rw.ResponseWriter.Write(b)
+}