.dockerignore

@@ -0,0 +1,9 @@
+.git
+.gitignore
+*.md
+LICENSE
+renovate.json
+*_test.go
+e2e_test.go
+__pycache__
+.env*

Dockerfile

@@ -14,7 +14,7 @@ RUN go mod download
 COPY . .
 
 # Build static binary
-RUN CGO_ENABLED=0 GOOS=linux go build -ldflags="-w -s" -o /tts-module .
+RUN CGO_ENABLED=0 GOOS=linux GOAMD64=v3 go build -ldflags="-w -s" -o /tts-module .
 
 # Runtime stage - scratch for minimal image
 FROM scratch

e2e_test.go

@@ -2,7 +2,6 @@ package main
 
 import (
 	"bytes"
-	"encoding/base64"
 	"encoding/json"
 	"io"
 	"net/http"
@@ -11,6 +10,9 @@ import (
 	"path/filepath"
 	"strconv"
 	"testing"
+
+	"git.daviestechlabs.io/daviestechlabs/handler-base/messages"
+	"github.com/vmihailenco/msgpack/v5"
 )
 
 // ────────────────────────────────────────────────────────────────────────────
@@ -63,26 +65,29 @@ func TestSynthesisE2E_StreamChunks(t *testing.T) {
 		chunkIdx := i / chunkSize
 		isLast := end >= len(audioBytes)
 
-		// Verify chunk message shape
-		msg := map[string]any{
-			"session_id":   "test-session",
-			"chunk_index":  chunkIdx,
-			"total_chunks": totalChunks,
-			"audio_b64":    base64.StdEncoding.EncodeToString(chunk),
-			"is_last":      isLast,
-			"sample_rate":  24000,
+		// Verify typed chunk struct
+		msg := messages.TTSAudioChunk{
+			SessionID:   "test-session",
+			ChunkIndex:  chunkIdx,
+			TotalChunks: totalChunks,
+			Audio:       chunk,
+			IsLast:      isLast,
+			SampleRate:  24000,
 		}
 
-		// Round-trip through JSON
-		data, _ := json.Marshal(msg)
-		var decoded map[string]any
-		json.Unmarshal(data, &decoded)
+		// Round-trip through msgpack
+		data, _ := msgpack.Marshal(&msg)
+		var decoded messages.TTSAudioChunk
+		msgpack.Unmarshal(data, &decoded)
 
-		if decoded["session_id"] != "test-session" {
-			t.Errorf("chunk %d: session = %v", chunkIdx, decoded["session_id"])
+		if decoded.SessionID != "test-session" {
+			t.Errorf("chunk %d: session = %v", chunkIdx, decoded.SessionID)
 		}
-		if decoded["is_last"] != isLast {
-			t.Errorf("chunk %d: is_last = %v, want %v", chunkIdx, decoded["is_last"], isLast)
+		if decoded.IsLast != isLast {
+			t.Errorf("chunk %d: is_last = %v, want %v", chunkIdx, decoded.IsLast, isLast)
+		}
+		if len(decoded.Audio) != len(chunk) {
+			t.Errorf("chunk %d: audio len = %d, want %d", chunkIdx, len(decoded.Audio), len(chunk))
 		}
 	}
 }
@@ -260,8 +265,14 @@ func BenchmarkAudioChunking(b *testing.B) {
 				end = len(audioBytes)
 			}
 			chunk := audioBytes[i:end]
-			_ = base64.StdEncoding.EncodeToString(chunk)
-			_ = totalChunks
+			msg := &messages.TTSAudioChunk{
+				SessionID:   "bench",
+				ChunkIndex:  i / chunkSize,
+				TotalChunks: totalChunks,
+				Audio:       chunk,
+				SampleRate:  24000,
+			}
+			msgpack.Marshal(msg)
 		}
 	}
 }

main.go

@@ -3,7 +3,6 @@ package main
 import (
 	"bytes"
 	"context"
-	"encoding/base64"
 	"encoding/json"
 	"fmt"
 	"io"
@@ -23,6 +22,7 @@ import (
 
 	"git.daviestechlabs.io/daviestechlabs/handler-base/config"
 	"git.daviestechlabs.io/daviestechlabs/handler-base/health"
+	"git.daviestechlabs.io/daviestechlabs/handler-base/messages"
 	"git.daviestechlabs.io/daviestechlabs/handler-base/natsutil"
 	"git.daviestechlabs.io/daviestechlabs/handler-base/telemetry"
 )
@@ -128,16 +128,16 @@ func (vr *VoiceRegistry) get(name string) *CustomVoice {
 	return vr.voices[name]
 }
 
-func (vr *VoiceRegistry) listVoices() []map[string]any {
+func (vr *VoiceRegistry) listVoices() []messages.TTSVoiceInfo {
 	vr.mu.RLock()
 	defer vr.mu.RUnlock()
-	result := make([]map[string]any, 0, len(vr.voices))
+	result := make([]messages.TTSVoiceInfo, 0, len(vr.voices))
 	for _, v := range vr.voices {
-		result = append(result, map[string]any{
-			"name":       v.Name,
-			"language":   v.Language,
-			"model_type": v.ModelType,
-			"created_at": v.CreatedAt,
+		result = append(result, messages.TTSVoiceInfo{
+			Name:      v.Name,
+			Language:  v.Language,
+			ModelType: v.ModelType,
+			CreatedAt: v.CreatedAt,
 		})
 	}
 	return result
@@ -222,11 +222,11 @@ func main() {
 
 	// Helper: publish status
 	publishStatus := func(sessionID, status, message string) {
-		statusMsg := map[string]any{
-			"session_id": sessionID,
-			"status":     status,
-			"message":    message,
-			"timestamp":  time.Now().Unix(),
+		statusMsg := &messages.TTSStatus{
+			SessionID: sessionID,
+			Status:    status,
+			Message:   message,
+			Timestamp: time.Now().Unix(),
 		}
 		_ = nc.Publish(fmt.Sprintf("%s.%s", statusSubjectPrefix, sessionID), statusMsg)
 	}
@@ -272,7 +272,7 @@ func main() {
 		return io.ReadAll(resp.Body)
 	}
 
-	// Helper: stream audio chunks
+	// Helper: stream audio chunks — raw bytes, no base64
 	streamAudio := func(sessionID string, audioBytes []byte) {
 		totalChunks := (len(audioBytes) + audioChunkSize - 1) / audioChunkSize
 		for i := 0; i < len(audioBytes); i += audioChunkSize {
@@ -284,14 +284,14 @@ func main() {
 			chunkIndex := i / audioChunkSize
 			isLast := end >= len(audioBytes)
 
-			msg := map[string]any{
-				"session_id":   sessionID,
-				"chunk_index":  chunkIndex,
-				"total_chunks": totalChunks,
-				"audio_b64":    base64.StdEncoding.EncodeToString(chunk),
-				"is_last":      isLast,
-				"timestamp":    time.Now().Unix(),
-				"sample_rate":  sampleRate,
+			msg := &messages.TTSAudioChunk{
+				SessionID:   sessionID,
+				ChunkIndex:  chunkIndex,
+				TotalChunks: totalChunks,
+				Audio:       chunk,
+				IsLast:      isLast,
+				Timestamp:   time.Now().Unix(),
+				SampleRate:  sampleRate,
 			}
 			_ = nc.Publish(fmt.Sprintf("%s.%s", audioSubjectPrefix, sessionID), msg)
 		}
@@ -307,17 +307,21 @@ func main() {
 		}
 		sessionID := parts[4]
 
-		data, err := natsutil.DecodeMsgpackMap(natMsg.Data)
+		req, err := natsutil.Decode[messages.TTSRequest](natMsg.Data)
 		if err != nil {
 			slog.Error("decode error", "error", err)
 			return
 		}
 
-		text := strVal(data, "text", "")
-		speaker := strVal(data, "speaker", defaultSpeaker)
-		language := strVal(data, "language", defaultLanguage)
-		speakerWavB64 := strVal(data, "speaker_wav_b64", "")
-		stream := boolVal(data, "stream", true)
+		text := req.Text
+		speaker := orDefault(req.Speaker, defaultSpeaker)
+		language := orDefault(req.Language, defaultLanguage)
+		speakerWavB64 := req.SpeakerWavB64
+		stream := req.Stream
+		// Default to streaming if not explicitly set (zero-value is false)
+		if !stream && text != "" {
+			stream = true
+		}
 
 		if text == "" {
 			slog.Warn("empty text", "session", sessionID)
@@ -338,11 +342,11 @@ func main() {
 		if stream {
 			streamAudio(sessionID, audioBytes)
 		} else {
-			msg := map[string]any{
-				"session_id":  sessionID,
-				"audio_b64":   base64.StdEncoding.EncodeToString(audioBytes),
-				"timestamp":   time.Now().Unix(),
-				"sample_rate": sampleRate,
+			msg := &messages.TTSFullResponse{
+				SessionID:  sessionID,
+				Audio:      audioBytes,
+				Timestamp:  time.Now().Unix(),
+				SampleRate: sampleRate,
 			}
 			_ = nc.Publish(fmt.Sprintf("%s.%s", audioSubjectPrefix, sessionID), msg)
 		}
@@ -358,11 +362,11 @@ func main() {
 
 	// Subscribe: list voices
 	if _, err := nc.Conn().Subscribe(voicesListSubject, func(msg *nats.Msg) {
-		resp := map[string]any{
-			"default_speaker": defaultSpeaker,
-			"custom_voices":   registry.listVoices(),
-			"last_refresh":    registry.lastRefresh.Unix(),
-			"timestamp":       time.Now().Unix(),
+		resp := &messages.TTSVoiceListResponse{
+			DefaultSpeaker: defaultSpeaker,
+			CustomVoices:   registry.listVoices(),
+			LastRefresh:    registry.lastRefresh.Unix(),
+			Timestamp:      time.Now().Unix(),
 		}
 		packed, _ := msgpack.Marshal(resp)
 		if msg.Reply != "" {
@@ -375,10 +379,10 @@ func main() {
 	// Subscribe: refresh voices
 	if _, err := nc.Conn().Subscribe(voicesRefreshSubject, func(msg *nats.Msg) {
 		count := registry.refresh()
-		resp := map[string]any{
-			"count":         count,
-			"custom_voices": registry.listVoices(),
-			"timestamp":     time.Now().Unix(),
+		resp := &messages.TTSVoiceRefreshResponse{
+			Count:        count,
+			CustomVoices: registry.listVoices(),
+			Timestamp:    time.Now().Unix(),
 		}
 		packed, _ := msgpack.Marshal(resp)
 		if msg.Reply != "" {
@@ -418,24 +422,6 @@ func main() {
 
 // Helpers
 
-func strVal(m map[string]any, key, fallback string) string {
-	if v, ok := m[key]; ok {
-		if s, ok := v.(string); ok {
-			return s
-		}
-	}
-	return fallback
-}
-
-func boolVal(m map[string]any, key string, fallback bool) bool {
-	if v, ok := m[key]; ok {
-		if b, ok := v.(bool); ok {
-			return b
-		}
-	}
-	return fallback
-}
-
 func getEnv(key, fallback string) string {
 	if v := os.Getenv(key); v != "" {
 		return v

main_test.go

@@ -8,6 +8,10 @@ import (
 	"path/filepath"
 	"strings"
 	"testing"
+
+	"git.daviestechlabs.io/daviestechlabs/handler-base/messages"
+	"git.daviestechlabs.io/daviestechlabs/handler-base/natsutil"
+	"github.com/vmihailenco/msgpack/v5"
 )
 
 func TestVoiceRegistryRefresh(t *testing.T) {
@@ -100,20 +104,58 @@ func TestSynthesizeHTTP(t *testing.T) {
 	}
 }
 
-func TestHelperFunctions(t *testing.T) {
-	m := map[string]any{"text": "hello", "stream": true, "count": 42}
+func TestTTSRequestDecode(t *testing.T) {
+	req := messages.TTSRequest{
+		Text:     "hello world",
+		Speaker:  "custom-en",
+		Language: "en",
+		Stream:   true,
+	}
+	data, err := msgpack.Marshal(&req)
+	if err != nil {
+		t.Fatal(err)
+	}
+	decoded, err := natsutil.Decode[messages.TTSRequest](data)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if decoded.Text != "hello world" {
+		t.Errorf("Text = %q", decoded.Text)
+	}
+	if decoded.Speaker != "custom-en" {
+		t.Errorf("Speaker = %q", decoded.Speaker)
+	}
+	if !decoded.Stream {
+		t.Error("Stream should be true")
+	}
+}
 
-	if got := strVal(m, "text", ""); got != "hello" {
-		t.Errorf("strVal(text) = %q", got)
+func TestTTSAudioChunkRoundtrip(t *testing.T) {
+	chunk := messages.TTSAudioChunk{
+		SessionID:   "sess-001",
+		ChunkIndex:  0,
+		TotalChunks: 2,
+		Audio:       make([]byte, 32768),
+		IsLast:      false,
+		Timestamp:   1234567890,
+		SampleRate:  24000,
 	}
-	if got := strVal(m, "missing", "def"); got != "def" {
-		t.Errorf("strVal(missing) = %q", got)
+	data, err := msgpack.Marshal(&chunk)
+	if err != nil {
+		t.Fatal(err)
 	}
-	if got := boolVal(m, "stream", false); !got {
-		t.Errorf("boolVal(stream) = %v", got)
+	var got messages.TTSAudioChunk
+	if err := msgpack.Unmarshal(data, &got); err != nil {
+		t.Fatal(err)
 	}
-	if got := boolVal(m, "missing", true); !got {
-		t.Errorf("boolVal(missing) = %v", got)
+	if got.SessionID != "sess-001" {
+		t.Errorf("SessionID = %q", got.SessionID)
+	}
+	if len(got.Audio) != 32768 {
+		t.Errorf("Audio len = %d", len(got.Audio))
+	}
+	if got.SampleRate != 24000 {
+		t.Errorf("SampleRate = %d", got.SampleRate)
 	}
 }