proxy,ui-svelte: replace old UI with svelte+playground

Replace the legacy React UI with the new Svelte-based one. Introduce a Playground in the UI to quickly test out text, image, text to speech and speech to text models behind llama-swap. 

Key Changes

New Svelte UI (ui-svelte/)

  - Multi-tab Playground with Chat, Image Generation, Audio Transcription, and Speech interfaces
  - Chat: message editing/regeneration, markdown rendering with LaTeX math support, image attachments, code syntax highlighting
  - Image: size selector, download/fullscreen viewing
  - Audio: transcription with peer support
  - Speech: voice caching with manual refresh, download button
  - Responsive mobile layout with collapsible navigation
  - XSS fixes and accessibility improvements

Proxy Improvements

  - Add gzip/brotli compression for UI static assets (proxy/ui_compress.go)
  - Add GET /v1/audio/voices?model={model} endpoint for voice listing
  - Add peer support for /v1/audio/transcriptions

proxy/helpers_test.go

@@ -71,11 +71,15 @@ func getTestSimpleResponderConfig(expectedMessage string) config.ModelConfig {
 }
 
 func getTestSimpleResponderConfigPort(expectedMessage string, port int) config.ModelConfig {
+	// Convert path to forward slashes for cross-platform compatibility
+	// Windows handles forward slashes in paths correctly
+	cmdPath := filepath.ToSlash(simpleResponderPath)
+
 	// Create a YAML string with just the values we want to set
 	yamlStr := fmt.Sprintf(`
 cmd: '%s --port %d --silent --respond %s'
 proxy: "http://127.0.0.1:%d"
-`, simpleResponderPath, port, expectedMessage, port)
+`, cmdPath, port, expectedMessage, port)
 
 	var cfg config.ModelConfig
 	if err := yaml.Unmarshal([]byte(yamlStr), &cfg); err != nil {

proxy/proxymanager.go

@@ -303,6 +303,7 @@ func (pm *ProxyManager) setupGinEngine() {
 	// Support audio/speech endpoint
 	pm.ginEngine.POST("/v1/audio/speech", pm.apiKeyAuth(), pm.proxyInferenceHandler)
 	pm.ginEngine.POST("/v1/audio/voices", pm.apiKeyAuth(), pm.proxyInferenceHandler)
+	pm.ginEngine.GET("/v1/audio/voices", pm.apiKeyAuth(), pm.proxyGETModelHandler)
 	pm.ginEngine.POST("/v1/audio/transcriptions", pm.apiKeyAuth(), pm.proxyOAIPostFormHandler)
 	pm.ginEngine.POST("/v1/images/generations", pm.apiKeyAuth(), pm.proxyInferenceHandler)
 	pm.ginEngine.POST("/v1/images/edits", pm.apiKeyAuth(), pm.proxyOAIPostFormHandler)
@@ -348,25 +349,35 @@ func (pm *ProxyManager) setupGinEngine() {
 	if err != nil {
 		pm.proxyLogger.Errorf("Failed to load React filesystem: %v", err)
 	} else {
+		// Serve files with compression support under /ui/*
+		// This handler checks for pre-compressed .br and .gz files
+		pm.ginEngine.GET("/ui/*filepath", func(c *gin.Context) {
+			filepath := strings.TrimPrefix(c.Param("filepath"), "/")
+			// Default to index.html for directory-like paths
+			if filepath == "" {
+				filepath = "index.html"
+			}
 
-		// serve files that exist under /ui/*
-		pm.ginEngine.StaticFS("/ui", reactFS)
+			ServeCompressedFile(reactFS, c.Writer, c.Request, filepath)
+		})
 
-		// server SPA for UI under /ui/*
+		// Serve SPA for UI under /ui/* - fallback to index.html for client-side routing
 		pm.ginEngine.NoRoute(func(c *gin.Context) {
 			if !strings.HasPrefix(c.Request.URL.Path, "/ui") {
 				c.AbortWithStatus(http.StatusNotFound)
 				return
 			}
 
-			file, err := reactFS.Open("index.html")
-			if err != nil {
-				c.String(http.StatusInternalServerError, err.Error())
+			// Check if this looks like a file request (has extension)
+			path := c.Request.URL.Path
+			if strings.Contains(path, ".") && !strings.HasSuffix(path, "/") {
+				// This was likely a file request that wasn't found
+				c.AbortWithStatus(http.StatusNotFound)
 				return
 			}
-			defer file.Close()
-			http.ServeContent(c.Writer, c.Request, "index.html", time.Now(), file)
 
+			// Serve index.html for SPA routing
+			ServeCompressedFile(reactFS, c.Writer, c.Request, "index.html")
 		})
 	}
 
@@ -744,15 +755,29 @@ func (pm *ProxyManager) proxyOAIPostFormHandler(c *gin.Context) {
 		return
 	}
 
+	// Look for a matching local model first, then check peers
+	var nextHandler func(modelID string, w http.ResponseWriter, r *http.Request) error
+	var useModelName string
+
 	modelID, found := pm.config.RealModelName(requestedModel)
-	if !found {
-		pm.sendErrorResponse(c, http.StatusBadRequest, fmt.Sprintf("could not find real modelID for %s", requestedModel))
-		return
+	if found {
+		processGroup, err := pm.swapProcessGroup(modelID)
+		if err != nil {
+			pm.sendErrorResponse(c, http.StatusInternalServerError, fmt.Sprintf("error swapping process group: %s", err.Error()))
+			return
+		}
+
+		useModelName = pm.config.Models[modelID].UseModelName
+		pm.proxyLogger.Debugf("ProxyManager using local Process for model: %s", requestedModel)
+		nextHandler = processGroup.ProxyRequest
+	} else if pm.peerProxy != nil && pm.peerProxy.HasPeerModel(requestedModel) {
+		pm.proxyLogger.Debugf("ProxyManager using ProxyPeer for model: %s", requestedModel)
+		modelID = requestedModel
+		nextHandler = pm.peerProxy.ProxyRequest
 	}
 
-	processGroup, err := pm.swapProcessGroup(modelID)
-	if err != nil {
-		pm.sendErrorResponse(c, http.StatusInternalServerError, fmt.Sprintf("error swapping process group: %s", err.Error()))
+	if nextHandler == nil {
+		pm.sendErrorResponse(c, http.StatusBadRequest, fmt.Sprintf("could not find suitable handler for %s", requestedModel))
 		return
 	}
 
@@ -768,8 +793,6 @@ func (pm *ProxyManager) proxyOAIPostFormHandler(c *gin.Context) {
 			// If this is the model field and we have a profile, use just the model name
 			if key == "model" {
 				// # issue #69 allow custom model names to be sent to upstream
-				useModelName := pm.config.Models[modelID].UseModelName
-
 				if useModelName != "" {
 					fieldValue = useModelName
 				} else {
@@ -839,9 +862,46 @@ func (pm *ProxyManager) proxyOAIPostFormHandler(c *gin.Context) {
 	modifiedReq.ContentLength = int64(requestBuffer.Len())
 
 	// Use the modified request for proxying
-	if err := processGroup.ProxyRequest(modelID, c.Writer, modifiedReq); err != nil {
+	if err := nextHandler(modelID, c.Writer, modifiedReq); err != nil {
 		pm.sendErrorResponse(c, http.StatusInternalServerError, fmt.Sprintf("error proxying request: %s", err.Error()))
-		pm.proxyLogger.Errorf("Error Proxying Request for processGroup %s and model %s", processGroup.id, modelID)
+		pm.proxyLogger.Errorf("Error Proxying Request for model %s", modelID)
+		return
+	}
+}
+
+func (pm *ProxyManager) proxyGETModelHandler(c *gin.Context) {
+	requestedModel := c.Query("model")
+	if requestedModel == "" {
+		pm.sendErrorResponse(c, http.StatusBadRequest, "missing required 'model' query parameter")
+		return
+	}
+
+	var nextHandler func(modelID string, w http.ResponseWriter, r *http.Request) error
+	var modelID string
+
+	if realModelID, found := pm.config.RealModelName(requestedModel); found {
+		processGroup, err := pm.swapProcessGroup(realModelID)
+		if err != nil {
+			pm.sendErrorResponse(c, http.StatusInternalServerError, fmt.Sprintf("error swapping process group: %s", err.Error()))
+			return
+		}
+		modelID = realModelID
+		pm.proxyLogger.Debugf("ProxyManager using local Process for model: %s", requestedModel)
+		nextHandler = processGroup.ProxyRequest
+	} else if pm.peerProxy != nil && pm.peerProxy.HasPeerModel(requestedModel) {
+		modelID = requestedModel
+		pm.proxyLogger.Debugf("ProxyManager using ProxyPeer for model: %s", requestedModel)
+		nextHandler = pm.peerProxy.ProxyRequest
+	}
+
+	if nextHandler == nil {
+		pm.sendErrorResponse(c, http.StatusBadRequest, fmt.Sprintf("could not find suitable handler for %s", requestedModel))
+		return
+	}
+
+	if err := nextHandler(modelID, c.Writer, c.Request); err != nil {
+		pm.sendErrorResponse(c, http.StatusInternalServerError, fmt.Sprintf("error proxying request: %s", err.Error()))
+		pm.proxyLogger.Errorf("Error Proxying GET Request for model %s", modelID)
 		return
 	}
 }

proxy/proxymanager_test.go

@@ -850,6 +850,43 @@ func TestProxyManager_UseModelName(t *testing.T) {
 	})
 }
 
+func TestProxyManager_AudioVoicesGETHandler(t *testing.T) {
+	conf := config.AddDefaultGroupToConfig(config.Config{
+		HealthCheckTimeout: 15,
+		Models: map[string]config.ModelConfig{
+			"model1": getTestSimpleResponderConfig("model1"),
+		},
+		LogLevel: "error",
+	})
+
+	proxy := New(conf)
+	defer proxy.StopProcesses(StopWaitForInflightRequest)
+
+	t.Run("successful GET with model query param", func(t *testing.T) {
+		req := httptest.NewRequest("GET", "/v1/audio/voices?model=model1", nil)
+		w := CreateTestResponseRecorder()
+		proxy.ServeHTTP(w, req)
+		assert.Equal(t, http.StatusOK, w.Code)
+		assert.Contains(t, w.Body.String(), "voice1")
+	})
+
+	t.Run("missing model query param returns 400", func(t *testing.T) {
+		req := httptest.NewRequest("GET", "/v1/audio/voices", nil)
+		w := CreateTestResponseRecorder()
+		proxy.ServeHTTP(w, req)
+		assert.Equal(t, http.StatusBadRequest, w.Code)
+		assert.Contains(t, w.Body.String(), "missing required 'model' query parameter")
+	})
+
+	t.Run("unknown model returns 400", func(t *testing.T) {
+		req := httptest.NewRequest("GET", "/v1/audio/voices?model=nonexistent", nil)
+		w := CreateTestResponseRecorder()
+		proxy.ServeHTTP(w, req)
+		assert.Equal(t, http.StatusBadRequest, w.Code)
+		assert.Contains(t, w.Body.String(), "could not find suitable handler")
+	})
+}
+
 func TestProxyManager_CORSOptionsHandler(t *testing.T) {
 	config := config.AddDefaultGroupToConfig(config.Config{
 		HealthCheckTimeout: 15,

proxy/ui_compress.go

@@ -0,0 +1,81 @@
+package proxy
+
+import (
+	"net/http"
+	"strings"
+)
+
+// selectEncoding chooses the best encoding based on Accept-Encoding header
+// Returns the encoding ("br", "gzip", or "") and the corresponding file extension
+func selectEncoding(acceptEncoding string) (encoding, ext string) {
+	if acceptEncoding == "" {
+		return "", ""
+	}
+
+	for _, part := range strings.Split(acceptEncoding, ",") {
+		enc := strings.TrimSpace(strings.SplitN(part, ";", 2)[0])
+		if enc == "br" {
+			return "br", ".br"
+		}
+	}
+
+	for _, part := range strings.Split(acceptEncoding, ",") {
+		enc := strings.TrimSpace(strings.SplitN(part, ";", 2)[0])
+		if enc == "gzip" {
+			return "gzip", ".gz"
+		}
+	}
+
+	return "", ""
+}
+
+// ServeCompressedFile serves a file with compression support.
+// It checks for pre-compressed versions and serves them with proper headers.
+func ServeCompressedFile(fs http.FileSystem, w http.ResponseWriter, r *http.Request, name string) {
+	encoding, ext := selectEncoding(r.Header.Get("Accept-Encoding"))
+
+	// Try to serve compressed version if client supports it
+	if encoding != "" {
+		if cf, err := fs.Open(name + ext); err == nil {
+			defer cf.Close()
+
+			// Verify it's a regular file (not a directory)
+			if stat, err := cf.Stat(); err == nil && !stat.IsDir() {
+				// Set the content encoding header
+				w.Header().Set("Content-Encoding", encoding)
+				w.Header().Add("Vary", "Accept-Encoding")
+
+				// Get original file info for content type detection
+				origFile, err := fs.Open(name)
+				if err == nil {
+					origFile.Close()
+				}
+
+				// Serve the compressed file
+				http.ServeContent(w, r, name, stat.ModTime(), cf)
+				return
+			}
+		}
+	}
+
+	// Fall back to serving the uncompressed file
+	file, err := fs.Open(name)
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusNotFound)
+		return
+	}
+	defer file.Close()
+
+	stat, err := file.Stat()
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+		return
+	}
+
+	if stat.IsDir() {
+		http.Error(w, "is a directory", http.StatusForbidden)
+		return
+	}
+
+	http.ServeContent(w, r, name, stat.ModTime(), file)
+}

proxy/ui_compress_test.go

@@ -0,0 +1,283 @@
+package proxy
+
+import (
+	"bytes"
+	"compress/gzip"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+	"testing/fstest"
+	"time"
+)
+
+func TestServeCompressedFile_Brotli(t *testing.T) {
+	// Create test content
+	content := []byte("This is test content that should be compressed with brotli")
+	brContent := []byte("fake-brotli-compressed-data")
+
+	// Create a test filesystem
+	mapFS := fstest.MapFS{
+		"test.js":    {Data: content, ModTime: time.Now()},
+		"test.js.br": {Data: brContent, ModTime: time.Now()},
+		"test.js.gz": {Data: []byte("fake-gzip-data"), ModTime: time.Now()},
+	}
+	fs := http.FS(mapFS)
+
+	req := httptest.NewRequest(http.MethodGet, "/test.js", nil)
+	req.Header.Set("Accept-Encoding", "br, gzip")
+	w := httptest.NewRecorder()
+
+	ServeCompressedFile(fs, w, req, "test.js")
+
+	resp := w.Result()
+	body, _ := io.ReadAll(resp.Body)
+
+	if resp.StatusCode != http.StatusOK {
+		t.Errorf("Expected status 200, got %d", resp.StatusCode)
+	}
+
+	// Check that brotli is used (preferred over gzip)
+	if encoding := resp.Header.Get("Content-Encoding"); encoding != "br" {
+		t.Errorf("Expected Content-Encoding 'br', got '%s'", encoding)
+	}
+
+	if vary := resp.Header.Get("Vary"); vary != "Accept-Encoding" {
+		t.Errorf("Expected Vary 'Accept-Encoding', got '%s'", vary)
+	}
+
+	if !bytes.Equal(body, brContent) {
+		t.Errorf("Expected brotli content, got %s", string(body))
+	}
+}
+
+func TestServeCompressedFile_Gzip(t *testing.T) {
+	// Create test content
+	content := []byte("This is test content that should be compressed with gzip")
+	gzContent := []byte("fake-gzip-compressed-data")
+
+	// Create a test filesystem without brotli
+	mapFS := fstest.MapFS{
+		"test.js":    {Data: content, ModTime: time.Now()},
+		"test.js.gz": {Data: gzContent, ModTime: time.Now()},
+	}
+	fs := http.FS(mapFS)
+
+	req := httptest.NewRequest(http.MethodGet, "/test.js", nil)
+	req.Header.Set("Accept-Encoding", "gzip")
+	w := httptest.NewRecorder()
+
+	ServeCompressedFile(fs, w, req, "test.js")
+
+	resp := w.Result()
+	body, _ := io.ReadAll(resp.Body)
+
+	if resp.StatusCode != http.StatusOK {
+		t.Errorf("Expected status 200, got %d", resp.StatusCode)
+	}
+
+	if encoding := resp.Header.Get("Content-Encoding"); encoding != "gzip" {
+		t.Errorf("Expected Content-Encoding 'gzip', got '%s'", encoding)
+	}
+
+	if !bytes.Equal(body, gzContent) {
+		t.Errorf("Expected gzip content, got %s", string(body))
+	}
+}
+
+func TestServeCompressedFile_UncompressedFallback(t *testing.T) {
+	// Create test content
+	content := []byte("This is uncompressed test content")
+
+	// Create a test filesystem without compressed versions
+	mapFS := fstest.MapFS{
+		"test.js": {Data: content, ModTime: time.Now()},
+	}
+	fs := http.FS(mapFS)
+
+	req := httptest.NewRequest(http.MethodGet, "/test.js", nil)
+	req.Header.Set("Accept-Encoding", "br, gzip")
+	w := httptest.NewRecorder()
+
+	ServeCompressedFile(fs, w, req, "test.js")
+
+	resp := w.Result()
+	body, _ := io.ReadAll(resp.Body)
+
+	if resp.StatusCode != http.StatusOK {
+		t.Errorf("Expected status 200, got %d", resp.StatusCode)
+	}
+
+	// Should not have Content-Encoding header since we're serving uncompressed
+	if encoding := resp.Header.Get("Content-Encoding"); encoding != "" {
+		t.Errorf("Expected no Content-Encoding, got '%s'", encoding)
+	}
+
+	if !bytes.Equal(body, content) {
+		t.Errorf("Expected original content, got %s", string(body))
+	}
+}
+
+func TestServeCompressedFile_NoAcceptEncoding(t *testing.T) {
+	// Create test content
+	content := []byte("This is test content")
+
+	// Create a test filesystem with compressed versions
+	mapFS := fstest.MapFS{
+		"test.js":    {Data: content, ModTime: time.Now()},
+		"test.js.br": {Data: []byte("brotli"), ModTime: time.Now()},
+		"test.js.gz": {Data: []byte("gzip"), ModTime: time.Now()},
+	}
+	fs := http.FS(mapFS)
+
+	req := httptest.NewRequest(http.MethodGet, "/test.js", nil)
+	// No Accept-Encoding header
+	w := httptest.NewRecorder()
+
+	ServeCompressedFile(fs, w, req, "test.js")
+
+	resp := w.Result()
+	body, _ := io.ReadAll(resp.Body)
+
+	if resp.StatusCode != http.StatusOK {
+		t.Errorf("Expected status 200, got %d", resp.StatusCode)
+	}
+
+	// Should serve uncompressed content
+	if encoding := resp.Header.Get("Content-Encoding"); encoding != "" {
+		t.Errorf("Expected no Content-Encoding, got '%s'", encoding)
+	}
+
+	if !bytes.Equal(body, content) {
+		t.Errorf("Expected original content, got %s", string(body))
+	}
+}
+
+func TestServeCompressedFile_NotFound(t *testing.T) {
+	mapFS := fstest.MapFS{}
+	fs := http.FS(mapFS)
+
+	req := httptest.NewRequest(http.MethodGet, "/nonexistent.js", nil)
+	w := httptest.NewRecorder()
+
+	ServeCompressedFile(fs, w, req, "nonexistent.js")
+
+	resp := w.Result()
+
+	if resp.StatusCode != http.StatusNotFound {
+		t.Errorf("Expected status 404, got %d", resp.StatusCode)
+	}
+}
+
+func TestSelectEncoding(t *testing.T) {
+	tests := []struct {
+		acceptEncoding string
+		wantEncoding   string
+		wantExt        string
+	}{
+		{"br, gzip", "br", ".br"},
+		{"gzip, deflate", "gzip", ".gz"},
+		{"gzip", "gzip", ".gz"},
+		{"br", "br", ".br"},
+		{"", "", ""},
+		{"deflate", "", ""},
+		{"br;q=1.0, gzip;q=0.5", "br", ".br"},
+		{"gzip;q=1.0, br;q=0.5", "br", ".br"},
+		{"browser", "", ""},
+		{"compress, deflate", "", ""},
+	}
+
+	for _, tt := range tests {
+		gotEncoding, gotExt := selectEncoding(tt.acceptEncoding)
+		if gotEncoding != tt.wantEncoding || gotExt != tt.wantExt {
+			t.Errorf("selectEncoding(%q) = (%q, %q), want (%q, %q)",
+				tt.acceptEncoding, gotEncoding, gotExt, tt.wantEncoding, tt.wantExt)
+		}
+	}
+}
+
+// Test with actual pre-compressed files from ui_dist
+func TestServeCompressedFile_RealFiles(t *testing.T) {
+	// Check if ui_dist exists
+	if _, err := os.Stat("./ui_dist"); os.IsNotExist(err) {
+		t.Skip("ui_dist not found, skipping real file test")
+	}
+
+	// Find a .js or .css file that has compressed versions
+	entries, err := os.ReadDir("./ui_dist/assets")
+	if err != nil {
+		t.Skipf("Could not read ui_dist/assets: %v", err)
+	}
+
+	var testFile string
+	for _, entry := range entries {
+		name := entry.Name()
+		if strings.HasSuffix(name, ".js") && !strings.HasSuffix(name, ".js.gz") && !strings.HasSuffix(name, ".js.br") {
+			// Check if compressed versions exist
+			base := strings.TrimSuffix(name, ".js")
+			if _, err := os.Stat(filepath.Join("./ui_dist/assets", base+".js.gz")); err == nil {
+				testFile = "assets/" + name
+				break
+			}
+		}
+	}
+
+	if testFile == "" {
+		t.Skip("No suitable test file found with compressed versions")
+	}
+
+	fs := http.FS(os.DirFS("./ui_dist"))
+
+	// Test brotli
+	t.Run("brotli", func(t *testing.T) {
+		req := httptest.NewRequest(http.MethodGet, "/"+testFile, nil)
+		req.Header.Set("Accept-Encoding", "br")
+		w := httptest.NewRecorder()
+
+		ServeCompressedFile(fs, w, req, testFile)
+
+		resp := w.Result()
+		if resp.StatusCode != http.StatusOK {
+			t.Fatalf("Expected status 200, got %d", resp.StatusCode)
+		}
+
+		if encoding := resp.Header.Get("Content-Encoding"); encoding != "br" {
+			t.Errorf("Expected Content-Encoding 'br', got '%s'", encoding)
+		}
+	})
+
+	// Test gzip
+	t.Run("gzip", func(t *testing.T) {
+		req := httptest.NewRequest(http.MethodGet, "/"+testFile, nil)
+		req.Header.Set("Accept-Encoding", "gzip")
+		w := httptest.NewRecorder()
+
+		ServeCompressedFile(fs, w, req, testFile)
+
+		resp := w.Result()
+		if resp.StatusCode != http.StatusOK {
+			t.Fatalf("Expected status 200, got %d", resp.StatusCode)
+		}
+
+		if encoding := resp.Header.Get("Content-Encoding"); encoding != "gzip" {
+			t.Errorf("Expected Content-Encoding 'gzip', got '%s'", encoding)
+		}
+
+		// Verify it's valid gzip
+		reader, err := gzip.NewReader(resp.Body)
+		if err != nil {
+			t.Errorf("Expected valid gzip content: %v", err)
+			return
+		}
+		defer reader.Close()
+
+		// Just read to verify it's valid
+		_, err = io.Copy(io.Discard, reader)
+		if err != nil {
+			t.Errorf("Failed to decompress gzip: %v", err)
+		}
+	})
+}