feat: add --proxybind flag to generate watch mode (#615)

cmd/templ/generatecmd/cmd.go

@@ -301,10 +301,13 @@ func (cmd *Generate) StartProxy(ctx context.Context) (p *proxy.Handler, err erro
 	if cmd.Args.ProxyPort == 0 {
 		cmd.Args.ProxyPort = 7331
 	}
-	p = proxy.New(cmd.Args.ProxyPort, target)
+	if cmd.Args.ProxyBind == "" {
+		cmd.Args.ProxyBind = "127.0.0.1"
+	}
+	p = proxy.New(cmd.Args.ProxyBind, cmd.Args.ProxyPort, target)
 	go func() {
 		cmd.Log.Info("Proxying", slog.String("from", p.URL), slog.String("to", p.Target.String()))
-		if err := http.ListenAndServe(fmt.Sprintf("127.0.0.1:%d", cmd.Args.ProxyPort), p); err != nil {
+		if err := http.ListenAndServe(fmt.Sprintf("%s:%d", cmd.Args.ProxyBind, cmd.Args.ProxyPort), p); err != nil {
 			cmd.Log.Error("Proxy failed", slog.Any("error", err))
 		}
 	}()

cmd/templ/generatecmd/main.go

@@ -17,6 +17,7 @@ type Arguments struct {
 	Watch                           bool
 	OpenBrowser                     bool
 	Command                         string
+	ProxyBind                       string
 	ProxyPort                       int
 	Proxy                           string
 	WorkerCount                     int

cmd/templ/generatecmd/proxy/proxy.go

@@ -90,7 +90,7 @@ func modifyResponse(r *http.Response) error {
 	return modifier(r)
 }
 
-func New(port int, target *url.URL) *Handler {
+func New(bind string, port int, target *url.URL) *Handler {
 	p := httputil.NewSingleHostReverseProxy(target)
 	p.ErrorLog = log.New(os.Stderr, "Proxy to target error: ", 0)
 	p.Transport = &roundTripper{
@@ -100,7 +100,7 @@ func New(port int, target *url.URL) *Handler {
 	}
 	p.ModifyResponse = modifyResponse
 	return &Handler{
-		URL:    fmt.Sprintf("http://127.0.0.1:%d", port),
+		URL:    fmt.Sprintf("http://%s:%d", bind, port),
 		Target: target,
 		p:      p,
 		sse:    sse.New(),

cmd/templ/generatecmd/testwatch/generate_test.go

@@ -307,14 +307,15 @@ loop:
 	}
 }
 
-func NewTestArgs(modRoot, appDir string, appPort int, proxyPort int) TestArgs {
+func NewTestArgs(modRoot, appDir string, appPort int, proxyBind string, proxyPort int) TestArgs {
 	return TestArgs{
 		ModRoot:   modRoot,
 		AppDir:    appDir,
 		AppPort:   appPort,
 		AppURL:    fmt.Sprintf("http://localhost:%d", appPort),
+		ProxyBind: proxyBind,
 		ProxyPort: proxyPort,
-		ProxyURL:  fmt.Sprintf("http://localhost:%d", proxyPort),
+		ProxyURL:  fmt.Sprintf("http://%s:%d", proxyBind, proxyPort),
 	}
 }
 
@@ -323,6 +324,7 @@ type TestArgs struct {
 	AppDir    string
 	AppPort   int
 	AppURL    string
+	ProxyBind string
 	ProxyPort int
 	ProxyURL  string
 }
@@ -349,8 +351,9 @@ func Setup(gzipEncoding bool) (args TestArgs, teardown func(t *testing.T), err e
 	if err != nil {
 		return args, teardown, fmt.Errorf("failed to get available port: %v", err)
 	}
+	proxyBind := "localhost"
 
-	args = NewTestArgs(moduleRoot, appDir, appPort, proxyPort)
+	args = NewTestArgs(moduleRoot, appDir, appPort, proxyBind, proxyPort)
 	ctx, cancel := context.WithCancel(context.Background())
 
 	var wg sync.WaitGroup
@@ -369,6 +372,7 @@ func Setup(gzipEncoding bool) (args TestArgs, teardown func(t *testing.T), err e
 			Path:              appDir,
 			Watch:             true,
 			Command:           command,
+			ProxyBind:         proxyBind,
 			ProxyPort:         proxyPort,
 			Proxy:             args.AppURL,
 			IncludeVersion:    false,

cmd/templ/main.go

@@ -86,6 +86,8 @@ Args:
     Set the URL to proxy after generating code and executing the command.
   -proxyport
     The port the proxy will listen on. (default 7331)
+  -proxybind
+    The address the proxy will listen on. (default 127.0.0.1)
   -w
     Number of workers to use when generating code. (default runtime.NumCPUs)
   -pprof
@@ -127,6 +129,7 @@ func generateCmd(w io.Writer, args []string) (code int) {
 	cmdFlag := cmd.String("cmd", "", "")
 	proxyFlag := cmd.String("proxy", "", "")
 	proxyPortFlag := cmd.Int("proxyport", 7331, "")
+	proxyBindFlag := cmd.String("proxybind", "127.0.0.1", "")
 	workerCountFlag := cmd.Int("w", runtime.NumCPU(), "")
 	pprofPortFlag := cmd.Int("pprof", 0, "")
 	keepOrphanedFilesFlag := cmd.Bool("keep-orphaned-files", false, "")
@@ -160,6 +163,7 @@ func generateCmd(w io.Writer, args []string) (code int) {
 		Command:                         *cmdFlag,
 		Proxy:                           *proxyFlag,
 		ProxyPort:                       *proxyPortFlag,
+		ProxyBind:                       *proxyBindFlag,
 		WorkerCount:                     *workerCountFlag,
 		GenerateSourceMapVisualisations: *sourceMapVisualisationsFlag,
 		IncludeVersion:                  *includeVersionFlag,

docs/docs/09-commands-and-tools/01-cli.md

@@ -44,6 +44,8 @@ Args:
     Set the URL to proxy after generating code and executing the command.
   -proxyport
     The port the proxy will listen on. (default 7331)
+  -proxybind
+    The address the proxy will listen on. (default 127.0.0.1)
   -w
     Number of workers to use when generating code. (default runtime.NumCPUs)
   -pprof

docs/docs/09-commands-and-tools/03-hot-reload.md

@@ -23,6 +23,8 @@ Finally, to trigger your web browser to reload automatically (without pressing F
 
 The `--proxy` argument starts a HTTP proxy which proxies requests to your app. For example, if your app runs on port 8080, you would use `--proxy="http://localhost:8080"`. The proxy inserts client-side JavaScript before the `</body>` tag that will cause the browser to reload the window when the app is restarted instead of you having to reload the page manually. Note that the html being served by the webserver MUST have a `<body>` tag, otherwise there will be no javascript injection thus making the browser not reload automatically.
 
+By default, the proxy binds to `127.0.0.1`. You can use `--proxybind` to bind to another address, e.g., `--proxybind="0.0.0.0"`.
+
 Altogether, to setup hot reload on an app that listens on port 8080, run the following.
 
 ```