style: gofmt + fix copylocks lint warning

- Replace msgpack encoding with protobuf wire format
- Update field names to proto convention (UserId, RequestId, EnableRag, etc.)
- Use messages.EffectiveQuery() standalone function
- Cast TopK to int32 for proto compatibility
- Rewrite tests for proto round-trips

Dockerfile

@@ -3,10 +3,13 @@ FROM golang:1.25-alpine AS builder
 
 WORKDIR /app
 
-RUN apk add --no-cache ca-certificates
+RUN apk add --no-cache ca-certificates git
+
+ENV GOPRIVATE=git.daviestechlabs.io
+ENV GONOSUMCHECK=git.daviestechlabs.io
 
 COPY go.mod go.sum ./
-RUN go mod download
+RUN --mount=type=secret,id=netrc,target=/root/.netrc go mod download
 
 COPY . .
 

e2e_test.go

@@ -3,14 +3,17 @@ package main
 import (
 	"context"
 	"encoding/json"
+	"fmt"
 	"net/http"
 	"net/http/httptest"
+	"strings"
+	"sync"
 	"testing"
 	"time"
 
 	"git.daviestechlabs.io/daviestechlabs/handler-base/clients"
 	"git.daviestechlabs.io/daviestechlabs/handler-base/messages"
-	"github.com/vmihailenco/msgpack/v5"
+	"google.golang.org/protobuf/proto"
 )
 
 // ────────────────────────────────────────────────────────────────────────────
@@ -164,33 +167,33 @@ func TestChatPipeline_LLMTimeout(t *testing.T) {
 }
 
 func TestChatPipeline_TypedDecoding(t *testing.T) {
-	// Verify typed struct decoding from msgpack (same path as OnTypedMessage).
-	raw := map[string]any{
-		"request_id":       "req-e2e-001",
-		"user_id":          "user-1",
-		"message":          "hello",
-		"premium":          true,
-		"enable_rag":       false,
-		"enable_streaming": false,
-		"system_prompt":    "Be brief.",
+	// Verify typed struct decoding from proto (same path as OnTypedMessage).
+	original := &messages.ChatRequest{
+		RequestId:       "req-e2e-001",
+		UserId:          "user-1",
+		Message:         "hello",
+		Premium:         true,
+		EnableRag:       false,
+		EnableStreaming: false,
+		SystemPrompt:    "Be brief.",
 	}
-	data, _ := msgpack.Marshal(raw)
+	data, _ := proto.Marshal(original)
 
 	var req messages.ChatRequest
-	if err := msgpack.Unmarshal(data, &req); err != nil {
+	if err := proto.Unmarshal(data, &req); err != nil {
 		t.Fatal(err)
 	}
 
-	if req.RequestID != "req-e2e-001" {
-		t.Errorf("RequestID = %q", req.RequestID)
+	if req.RequestId != "req-e2e-001" {
+		t.Errorf("RequestID = %q", req.RequestId)
 	}
-	if req.UserID != "user-1" {
-		t.Errorf("UserID = %q", req.UserID)
+	if req.UserId != "user-1" {
+		t.Errorf("UserID = %q", req.UserId)
 	}
-	if req.EffectiveQuery() != "hello" {
-		t.Errorf("query = %q", req.EffectiveQuery())
+	if messages.EffectiveQuery(&req) != "hello" {
+		t.Errorf("query = %q", messages.EffectiveQuery(&req))
 	}
-	if req.EnableRAG {
+	if req.EnableRag {
 		t.Error("EnableRAG should be false")
 	}
 	if req.SystemPrompt != "Be brief." {
@@ -198,6 +201,220 @@ func TestChatPipeline_TypedDecoding(t *testing.T) {
 	}
 }
 
+// ────────────────────────────────────────────────────────────────────────────
+// Streaming tests: exercise StreamGenerate path (the real SSE pipeline)
+// ────────────────────────────────────────────────────────────────────────────
+
+// sseChunk builds an OpenAI-compatible SSE data line.
+func sseChunk(content string) string {
+	return fmt.Sprintf("data: {\"choices\":[{\"delta\":{\"content\":%q}}]}\n\n", content)
+}
+
+// newStreamingLLM creates a mock LLM server that responds with SSE-streamed tokens.
+func newStreamingLLM(t *testing.T, tokens []string) *httptest.Server {
+	t.Helper()
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		var req map[string]any
+		_ = json.NewDecoder(r.Body).Decode(&req)
+		// Verify stream=true was requested.
+		if stream, ok := req["stream"].(bool); !ok || !stream {
+			t.Error("expected stream=true in request body")
+		}
+
+		w.Header().Set("Content-Type", "text/event-stream")
+		w.Header().Set("Cache-Control", "no-cache")
+		flusher, _ := w.(http.Flusher)
+
+		// Role-only chunk (should be skipped by StreamGenerate)
+		_, _ = fmt.Fprintf(w, "data: {\"choices\":[{\"delta\":{\"role\":\"assistant\"}}]}\n\n")
+		if flusher != nil {
+			flusher.Flush()
+		}
+
+		for _, tok := range tokens {
+			_, _ = fmt.Fprint(w, sseChunk(tok))
+			if flusher != nil {
+				flusher.Flush()
+			}
+		}
+		_, _ = fmt.Fprintf(w, "data: [DONE]\n\n")
+		if flusher != nil {
+			flusher.Flush()
+		}
+	}))
+	t.Cleanup(srv.Close)
+	return srv
+}
+
+func TestChatPipeline_StreamGenerate(t *testing.T) {
+	tokens := []string{"Paris", " is", " the", " capital", " of", " France", "."}
+	srv := newStreamingLLM(t, tokens)
+	llm := clients.NewLLMClient(srv.URL, 5*time.Second)
+
+	var mu sync.Mutex
+	var received []string
+	full, err := llm.StreamGenerate(context.Background(), "capital of France?", "", "", func(token string) {
+		mu.Lock()
+		defer mu.Unlock()
+		received = append(received, token)
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if full != "Paris is the capital of France." {
+		t.Errorf("full = %q", full)
+	}
+	if len(received) != len(tokens) {
+		t.Errorf("callback count = %d, want %d", len(received), len(tokens))
+	}
+	for i, tok := range tokens {
+		if received[i] != tok {
+			t.Errorf("token[%d] = %q, want %q", i, received[i], tok)
+		}
+	}
+}
+
+func TestChatPipeline_StreamWithSystemPrompt(t *testing.T) {
+	srv := newStreamingLLM(t, []string{"Hello", "!"})
+	llm := clients.NewLLMClient(srv.URL, 5*time.Second)
+
+	full, err := llm.StreamGenerate(context.Background(), "greet me", "", "You are a friendly assistant.", func(token string) {})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if full != "Hello!" {
+		t.Errorf("full = %q", full)
+	}
+}
+
+func TestChatPipeline_StreamWithRAGContext(t *testing.T) {
+	m := newMockBackends(t)
+	srv := newStreamingLLM(t, []string{"The", " answer", " is", " 42"})
+	embeddings := clients.NewEmbeddingsClient(m.Embeddings.URL, 5*time.Second, "bge")
+	llm := clients.NewLLMClient(srv.URL, 5*time.Second)
+
+	ctx := context.Background()
+
+	// 1. Embed
+	embedding, err := embeddings.EmbedSingle(ctx, "deep thought")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(embedding) == 0 {
+		t.Fatal("empty embedding")
+	}
+
+	// 2. Stream with context
+	var tokens []string
+	full, err := llm.StreamGenerate(ctx, "deep thought", "The answer to everything is 42.", "", func(tok string) {
+		tokens = append(tokens, tok)
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if full != "The answer is 42" {
+		t.Errorf("full = %q", full)
+	}
+	if len(tokens) != 4 {
+		t.Errorf("token count = %d, want 4", len(tokens))
+	}
+}
+
+func TestChatPipeline_StreamNilCallback(t *testing.T) {
+	srv := newStreamingLLM(t, []string{"ok"})
+	llm := clients.NewLLMClient(srv.URL, 5*time.Second)
+
+	full, err := llm.StreamGenerate(context.Background(), "test", "", "", nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if full != "ok" {
+		t.Errorf("full = %q", full)
+	}
+}
+
+func TestChatPipeline_StreamTimeout(t *testing.T) {
+	slow := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		time.Sleep(200 * time.Millisecond)
+		w.Header().Set("Content-Type", "text/event-stream")
+		_, _ = fmt.Fprint(w, sseChunk("late"))
+		_, _ = fmt.Fprint(w, "data: [DONE]\n\n")
+	}))
+	defer slow.Close()
+
+	llm := clients.NewLLMClient(slow.URL, 100*time.Millisecond)
+	_, err := llm.StreamGenerate(context.Background(), "hello", "", "", nil)
+	if err == nil {
+		t.Error("expected timeout error")
+	}
+}
+
+func TestChatPipeline_StreamHTTPError(t *testing.T) {
+	errSrv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusInternalServerError)
+		_, _ = w.Write([]byte("internal error"))
+	}))
+	defer errSrv.Close()
+
+	llm := clients.NewLLMClient(errSrv.URL, 5*time.Second)
+	_, err := llm.StreamGenerate(context.Background(), "hello", "", "", nil)
+	if err == nil {
+		t.Error("expected error for HTTP 500")
+	}
+	if !strings.Contains(err.Error(), "500") {
+		t.Errorf("error = %q, should mention status 500", err)
+	}
+}
+
+func TestChatPipeline_StreamContextCanceled(t *testing.T) {
+	ctx, cancel := context.WithCancel(context.Background())
+	cancel() // cancel immediately
+
+	srv := newStreamingLLM(t, []string{"should", "not", "arrive"})
+	llm := clients.NewLLMClient(srv.URL, 5*time.Second)
+
+	_, err := llm.StreamGenerate(ctx, "hello", "", "", nil)
+	if err == nil {
+		t.Error("expected context canceled error")
+	}
+}
+
+func TestChatPipeline_StreamFallbackToNonStreaming(t *testing.T) {
+	// Simulate the branching in main.go: non-streaming uses Generate(),
+	// streaming uses StreamGenerate(). Verify both paths work from same mock.
+	m := newMockBackends(t)
+	streamSrv := newStreamingLLM(t, []string{"streamed", " answer"})
+
+	nonStreamLLM := clients.NewLLMClient(m.LLM.URL, 5*time.Second)
+	streamLLM := clients.NewLLMClient(streamSrv.URL, 5*time.Second)
+
+	ctx := context.Background()
+
+	// Non-streaming path
+	resp1, err := nonStreamLLM.Generate(ctx, "hello", "", "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if resp1 != "Paris is the capital of France." {
+		t.Errorf("non-stream = %q", resp1)
+	}
+
+	// Streaming path
+	var tokens []string
+	resp2, err := streamLLM.StreamGenerate(ctx, "hello", "", "", func(tok string) {
+		tokens = append(tokens, tok)
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if resp2 != "streamed answer" {
+		t.Errorf("stream = %q", resp2)
+	}
+	if len(tokens) != 2 {
+		t.Errorf("token count = %d", len(tokens))
+	}
+}
+
 // ────────────────────────────────────────────────────────────────────────────
 // Benchmark: full chat pipeline overhead (mock backends)
 // ────────────────────────────────────────────────────────────────────────────
@@ -245,3 +462,23 @@ func BenchmarkChatPipeline_RAGFlow(b *testing.B) {
 		_, _ = llm.Generate(ctx, "question", "context", "")
 	}
 }
+
+func BenchmarkChatPipeline_StreamGenerate(b *testing.B) {
+	tokens := []string{"one", " two", " three", " four", " five"}
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "text/event-stream")
+		for _, tok := range tokens {
+			_, _ = fmt.Fprintf(w, "data: {\"choices\":[{\"delta\":{\"content\":%q}}]}\n\n", tok)
+		}
+		_, _ = fmt.Fprint(w, "data: [DONE]\n\n")
+	}))
+	defer srv.Close()
+
+	llm := clients.NewLLMClient(srv.URL, 10*time.Second)
+	ctx := context.Background()
+
+	b.ResetTimer()
+	for b.Loop() {
+		_, _ = llm.StreamGenerate(ctx, "question", "", "", func(string) {})
+	}
+}

go.mod

@@ -3,9 +3,9 @@ module git.daviestechlabs.io/daviestechlabs/chat-handler
 go 1.25.1
 
 require (
-	git.daviestechlabs.io/daviestechlabs/handler-base v0.1.3
+	git.daviestechlabs.io/daviestechlabs/handler-base v1.0.0
 	github.com/nats-io/nats.go v1.48.0
-	github.com/vmihailenco/msgpack/v5 v5.4.1
+	google.golang.org/protobuf v1.36.11
 )
 
 require (
@@ -19,7 +19,6 @@ require (
 	github.com/klauspost/compress v1.18.0 // indirect
 	github.com/nats-io/nkeys v0.4.11 // indirect
 	github.com/nats-io/nuid v1.0.1 // indirect
-	github.com/vmihailenco/tagparser/v2 v2.0.0 // indirect
 	go.opentelemetry.io/auto/sdk v1.2.1 // indirect
 	go.opentelemetry.io/otel v1.40.0 // indirect
 	go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc v1.40.0 // indirect
@@ -37,5 +36,4 @@ require (
 	google.golang.org/genproto/googleapis/api v0.0.0-20260128011058-8636f8732409 // indirect
 	google.golang.org/genproto/googleapis/rpc v0.0.0-20260128011058-8636f8732409 // indirect
 	google.golang.org/grpc v1.78.0 // indirect
-	google.golang.org/protobuf v1.36.11 // indirect
 )

go.sum

@@ -1,5 +1,5 @@
-git.daviestechlabs.io/daviestechlabs/handler-base v0.1.3 h1:uYog8B839ulqrWoht3qqCvT7CnR3e2skpaLZc2Pg3GI=
-git.daviestechlabs.io/daviestechlabs/handler-base v0.1.3/go.mod h1:M3HgvUDWnRn7cX3BE8l+HvoCUYtmRr5OoumB+hnRHoE=
+git.daviestechlabs.io/daviestechlabs/handler-base v1.0.0 h1:pB3ehOKaDYQfbyRBKQXrB9curqSFteLrDveoElRKnBY=
+git.daviestechlabs.io/daviestechlabs/handler-base v1.0.0/go.mod h1:zocOHFt8yY3cW4+Xi37sNr5Tw7KcjGFSZqgWYxPWyqA=
 github.com/cenkalti/backoff/v5 v5.0.3 h1:ZN+IMa753KfX5hd8vVaMixjnqRZ3y8CuJKRKj1xcsSM=
 github.com/cenkalti/backoff/v5 v5.0.3/go.mod h1:rkhZdG3JZukswDf7f0cwqPNk4K0sa+F97BxZthm/crw=
 github.com/cespare/xxhash/v2 v2.3.0 h1:UL815xU9SqsFlibzuggzjXhog7bL6oX9BbNZnL2UFvs=
@@ -33,10 +33,6 @@ github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZb
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U=
 github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U=
-github.com/vmihailenco/msgpack/v5 v5.4.1 h1:cQriyiUvjTwOHg8QZaPihLWeRAAVoCpE00IUPn0Bjt8=
-github.com/vmihailenco/msgpack/v5 v5.4.1/go.mod h1:GaZTsDaehaPpQVyxrf5mtQlH+pc21PIudVV/E3rRQok=
-github.com/vmihailenco/tagparser/v2 v2.0.0 h1:y09buUbR+b5aycVFQs/g70pqKVZNBmxwAhO7/IwNM9g=
-github.com/vmihailenco/tagparser/v2 v2.0.0/go.mod h1:Wri+At7QHww0WTrCBeu4J6bNtoV6mEfg5OIWRZA9qds=
 go.opentelemetry.io/auto/sdk v1.2.1 h1:jXsnJ4Lmnqd11kwkBV2LgLoFMZKizbCi5fNZ/ipaZ64=
 go.opentelemetry.io/auto/sdk v1.2.1/go.mod h1:KRTj+aOaElaLi+wW1kO/DZRXwkF4C5xPbEe3ZiIhN7Y=
 go.opentelemetry.io/otel v1.40.0 h1:oA5YeOcpRTXq6NN7frwmwFR0Cn3RhTVZvXsP4duvCms=

main.go

@@ -16,6 +16,7 @@ import (
 	"git.daviestechlabs.io/daviestechlabs/handler-base/handler"
 	"git.daviestechlabs.io/daviestechlabs/handler-base/messages"
 	"git.daviestechlabs.io/daviestechlabs/handler-base/natsutil"
+	"google.golang.org/protobuf/proto"
 )
 
 func main() {
@@ -45,23 +46,23 @@ func main() {
 
 	h := handler.New("ai.chat.user.*.message", cfg)
 
-	h.OnTypedMessage(func(ctx context.Context, msg *nats.Msg) (any, error) {
-		req, err := natsutil.Decode[messages.ChatRequest](msg.Data)
-		if err != nil {
+	h.OnTypedMessage(func(ctx context.Context, msg *nats.Msg) (proto.Message, error) {
+		var req messages.ChatRequest
+		if err := natsutil.Decode(msg.Data, &req); err != nil {
 			slog.Error("decode failed", "error", err)
 			return &messages.ErrorResponse{Error: true, Message: err.Error(), Type: "DecodeError"}, nil
 		}
 
-		query := req.EffectiveQuery()
-		requestID := req.RequestID
+		query := messages.EffectiveQuery(&req)
+		requestID := req.RequestId
 		if requestID == "" {
 			requestID = "unknown"
 		}
-		userID := req.UserID
+		userID := req.UserId
 		if userID == "" {
 			userID = "unknown"
 		}
-		enableRAG := req.EnableRAG
+		enableRAG := req.EnableRag
 		if !enableRAG && req.Premium {
 			enableRAG = true
 		}
@@ -71,13 +72,13 @@ func main() {
 		}
 		topK := req.TopK
 		if topK == 0 {
-			topK = ragTopK
+			topK = int32(ragTopK)
 		}
 		collection := req.Collection
 		if collection == "" {
 			collection = ragCollection
 		}
-		reqEnableTTS := req.EnableTTS || enableTTS
+		reqEnableTTS := req.EnableTts || enableTTS
 		systemPrompt := req.SystemPrompt
 		responseSubject := req.ResponseSubject
 		if responseSubject == "" {
@@ -157,44 +158,38 @@ func main() {
 			}
 		}
 
-		// 5. Generate LLM response
-		responseText, err := llm.Generate(ctx, query, contextText, systemPrompt)
+		// 5. Generate LLM response (streaming when requested)
+		var responseText string
+		var err error
+		if req.EnableStreaming {
+			streamSubject := fmt.Sprintf("ai.chat.response.stream.%s", requestID)
+			responseText, err = llm.StreamGenerate(ctx, query, contextText, systemPrompt, func(token string) {
+				_ = h.NATS.Publish(streamSubject, &messages.ChatStreamChunk{
+					RequestId: requestID,
+					Type:      "chunk",
+					Content:   token,
+					Timestamp: messages.Timestamp(),
+				})
+			})
+			_ = h.NATS.Publish(streamSubject, &messages.ChatStreamChunk{
+				RequestId: requestID,
+				Type:      "done",
+				Done:      true,
+				Timestamp: messages.Timestamp(),
+			})
+		} else {
+			responseText, err = llm.Generate(ctx, query, contextText, systemPrompt)
+		}
 		if err != nil {
 			slog.Error("LLM generation failed", "error", err)
 			return &messages.ChatResponse{
-				UserID:  userID,
+				UserId:  userID,
 				Success: false,
 				Error:   err.Error(),
 			}, nil
 		}
 
-		// 6. Stream chunks if requested
-		if req.EnableStreaming {
-			streamSubject := fmt.Sprintf("ai.chat.response.stream.%s", requestID)
-			words := strings.Fields(responseText)
-			chunkSize := 4
-			for i := 0; i < len(words); i += chunkSize {
-				end := i + chunkSize
-				if end > len(words) {
-					end = len(words)
-				}
-				chunk := strings.Join(words[i:end], " ")
-				_ = h.NATS.Publish(streamSubject, &messages.ChatStreamChunk{
-					RequestID: requestID,
-					Type:      "chunk",
-					Content:   chunk,
-					Timestamp: messages.Timestamp(),
-				})
-			}
-			_ = h.NATS.Publish(streamSubject, &messages.ChatStreamChunk{
-				RequestID: requestID,
-				Type:      "done",
-				Done:      true,
-				Timestamp: messages.Timestamp(),
-			})
-		}
-
-		// 7. Optional TTS — audio as raw bytes (no base64)
+		// 6. Optional TTS — audio as raw bytes (no base64)
 		var audio []byte
 		if reqEnableTTS && tts != nil {
 			audioBytes, err := tts.Synthesize(ctx, responseText, ttsLanguage, "")
@@ -206,15 +201,15 @@ func main() {
 		}
 
 		result := &messages.ChatResponse{
-			UserID:       userID,
+			UserId:       userID,
 			Response:     responseText,
 			ResponseText: responseText,
-			UsedRAG:      usedRAG,
+			UsedRag:      usedRAG,
 			Success:      true,
 			Audio:        audio,
 		}
 		if includeSources {
-			result.RAGSources = ragSources
+			result.RagSources = ragSources
 		}
 
 		// Publish to the response subject the frontend is waiting on

main_test.go

@@ -5,28 +5,31 @@ import (
 	"testing"
 
 	"git.daviestechlabs.io/daviestechlabs/handler-base/messages"
-	"github.com/vmihailenco/msgpack/v5"
+	"google.golang.org/protobuf/proto"
 )
 
 func TestChatRequestDecode(t *testing.T) {
-	// Verify a msgpack-encoded map decodes cleanly into typed struct.
-	raw := map[string]any{
-		"request_id": "req-1",
-		"user_id":    "user-1",
-		"message":    "hello",
-		"premium":    true,
-		"top_k":      10,
+	// Verify a proto-encoded struct round-trips cleanly.
+	original := &messages.ChatRequest{
+		RequestId: "req-1",
+		UserId:    "user-1",
+		Message:   "hello",
+		Premium:   true,
+		TopK:      10,
 	}
-	data, _ := msgpack.Marshal(raw)
-	var req messages.ChatRequest
-	if err := msgpack.Unmarshal(data, &req); err != nil {
+	data, err := proto.Marshal(original)
+	if err != nil {
 		t.Fatal(err)
 	}
-	if req.RequestID != "req-1" {
-		t.Errorf("RequestID = %q", req.RequestID)
+	var req messages.ChatRequest
+	if err := proto.Unmarshal(data, &req); err != nil {
+		t.Fatal(err)
 	}
-	if req.EffectiveQuery() != "hello" {
-		t.Errorf("EffectiveQuery = %q", req.EffectiveQuery())
+	if req.RequestId != "req-1" {
+		t.Errorf("RequestID = %q", req.RequestId)
+	}
+	if messages.EffectiveQuery(&req) != "hello" {
+		t.Errorf("EffectiveQuery = %q", messages.EffectiveQuery(&req))
 	}
 	if !req.Premium {
 		t.Error("Premium should be true")
@@ -38,21 +41,21 @@ func TestChatRequestDecode(t *testing.T) {
 
 func TestChatResponseRoundtrip(t *testing.T) {
 	resp := &messages.ChatResponse{
-		UserID:   "user-1",
+		UserId:   "user-1",
 		Response: "answer",
 		Success:  true,
 		Audio:    []byte{0x01, 0x02, 0x03},
 	}
-	data, err := msgpack.Marshal(resp)
+	data, err := proto.Marshal(resp)
 	if err != nil {
 		t.Fatal(err)
 	}
 	var decoded messages.ChatResponse
-	if err := msgpack.Unmarshal(data, &decoded); err != nil {
+	if err := proto.Unmarshal(data, &decoded); err != nil {
 		t.Fatal(err)
 	}
-	if decoded.UserID != "user-1" || !decoded.Success {
-		t.Errorf("decoded = %+v", decoded)
+	if decoded.UserId != "user-1" || !decoded.Success {
+		t.Errorf("decoded: UserId=%s, Success=%v", decoded.UserId, decoded.Success)
 	}
 	if len(decoded.Audio) != 3 {
 		t.Errorf("audio len = %d", len(decoded.Audio))