feat: add Docker support and logging enhancements

- Introduced Dockerfile and .dockerignore for containerization of the backend service.
- Added logging configuration with support for daily rolling logs and customizable log levels.
- Enhanced the server to utilize structured logging with zap, including detailed request and error logging.
- Updated configuration to include logging parameters and proxy settings.
- Implemented tests for logging configuration and proxy settings.

backend/internal/api/ws_handler.go

@@ -9,6 +9,7 @@ import (
 
 	"github.com/gin-gonic/gin"
 	"github.com/gorilla/websocket"
+	"go.uber.org/zap"
 
 	"monica-go-completion-backend/internal/completion"
 )
@@ -62,10 +63,35 @@ func registerWSRoutes(router *gin.Engine, service CompletionService, opts RouteO
 	handler := func(c *gin.Context, defaultLanguage string) {
 		conn, err := wsUpgrader.Upgrade(c.Writer, c.Request, nil)
 		if err != nil {
+			zap.L().Warn(
+				"ws upgrade failed",
+				zap.String("traceId", traceIDFromGin(c)),
+				zap.String("path", c.Request.URL.Path),
+				zap.String("clientIP", c.ClientIP()),
+				zap.Error(err),
+			)
 			return
 		}
 		defer conn.Close()
 
+		traceID := traceIDFromGin(c)
+		zap.L().Info(
+			"ws connection opened",
+			zap.String("traceId", traceID),
+			zap.String("path", c.Request.URL.Path),
+			zap.String("language", defaultLanguage),
+			zap.String("clientIP", c.ClientIP()),
+		)
+		defer func() {
+			zap.L().Info(
+				"ws connection closed",
+				zap.String("traceId", traceID),
+				zap.String("path", c.Request.URL.Path),
+				zap.String("language", defaultLanguage),
+				zap.String("clientIP", c.ClientIP()),
+			)
+		}()
+
 		conn.SetReadLimit(opts.MaxBodyBytes)
 
 		var writeMu sync.Mutex
@@ -74,9 +100,15 @@ func registerWSRoutes(router *gin.Engine, service CompletionService, opts RouteO
 			// 单连接串行读取消息，写操作通过 writeMu 保证并发安全。
 			_, payload, err := conn.ReadMessage()
 			if err != nil {
+				zap.L().Info(
+					"ws read loop ended",
+					zap.String("traceId", traceID),
+					zap.String("path", c.Request.URL.Path),
+					zap.Error(err),
+				)
 				break
 			}
-			handleWSMessage(conn, &writeMu, service, payload, defaultLanguage, opts)
+			handleWSMessage(conn, &writeMu, service, payload, defaultLanguage, traceID, c.ClientIP(), opts)
 		}
 	}
 
@@ -95,14 +127,22 @@ func handleWSMessage(
 	service CompletionService,
 	payload []byte,
 	defaultLanguage string,
+	traceID string,
+	clientIP string,
 	opts RouteOptions,
 ) {
-	if tryHandleRPCMessage(conn, writeMu, service, payload, defaultLanguage, opts) {
+	if tryHandleRPCMessage(conn, writeMu, service, payload, defaultLanguage, traceID, clientIP, opts) {
 		return
 	}
 
 	var req wsCompletionRequest
 	if err := json.Unmarshal(payload, &req); err != nil {
+		zap.L().Warn(
+			"ws invalid json payload",
+			zap.String("traceId", traceID),
+			zap.String("clientIP", clientIP),
+			zap.Error(err),
+		)
 		sendWSResponse(conn, writeMu, wsCompletionResponse{
 			ID:    "",
 			Error: "invalid JSON payload",
@@ -113,7 +153,7 @@ func handleWSMessage(
 		req.Language = defaultLanguage
 	}
 
-	processWSCompletion(conn, writeMu, service, req, opts)
+	processWSCompletion(conn, writeMu, service, req, traceID, clientIP, opts)
 }
 
 // tryHandleRPCMessage 处理 JSON-RPC 2.0 请求，返回 true 表示消息已消费。
@@ -123,6 +163,8 @@ func tryHandleRPCMessage(
 	service CompletionService,
 	payload []byte,
 	defaultLanguage string,
+	traceID string,
+	clientIP string,
 	opts RouteOptions,
 ) bool {
 	var rpcReq wsRPCRequest
@@ -148,6 +190,13 @@ func tryHandleRPCMessage(
 
 	var req wsCompletionRequest
 	if err := json.Unmarshal(rpcReq.Params, &req); err != nil {
+		zap.L().Warn(
+			"ws rpc invalid params",
+			zap.String("traceId", traceID),
+			zap.String("clientIP", clientIP),
+			zap.String("method", rpcReq.Method),
+			zap.Error(err),
+		)
 		// 参数反序列化失败按 invalid params 处理。
 		sendWSRPCResponse(conn, writeMu, wsRPCResponse{
 			JSONRPC: "2.0",
@@ -179,6 +228,16 @@ func tryHandleRPCMessage(
 		Character: req.Character,
 	})
 	if err != nil {
+		zap.L().Warn(
+			"ws rpc completion failed",
+			zap.String("traceId", traceID),
+			zap.String("clientIP", clientIP),
+			zap.String("method", rpcReq.Method),
+			zap.String("language", req.Language),
+			zap.String("sessionId", req.SessionID),
+			zap.String("uri", req.URI),
+			zap.Error(err),
+		)
 		sendWSRPCResponse(conn, writeMu, wsRPCResponse{
 			JSONRPC: "2.0",
 			ID:      rpcReq.ID,
@@ -204,6 +263,8 @@ func processWSCompletion(
 	writeMu *sync.Mutex,
 	service CompletionService,
 	req wsCompletionRequest,
+	traceID string,
+	clientIP string,
 	opts RouteOptions,
 ) {
 	ctx, cancel := context.WithTimeout(context.Background(), opts.RequestTimeout)
@@ -237,6 +298,17 @@ func processWSCompletion(
 				ownerID = ownedErr.OwnerID
 			}
 		}
+		zap.L().Warn(
+			"ws completion failed",
+			zap.String("traceId", traceID),
+			zap.String("clientIP", clientIP),
+			zap.String("language", req.Language),
+			zap.String("sessionId", req.SessionID),
+			zap.String("uri", req.URI),
+			zap.String("routeTo", routeTo),
+			zap.String("ownerId", ownerID),
+			zap.Error(err),
+		)
 		sendWSResponse(conn, writeMu, wsCompletionResponse{
 			ID:      req.ID,
 			RouteTo: routeTo,
@@ -245,6 +317,15 @@ func processWSCompletion(
 		})
 		return
 	}
+	zap.L().Info(
+		"ws completion success",
+		zap.String("traceId", traceID),
+		zap.String("clientIP", clientIP),
+		zap.String("language", req.Language),
+		zap.String("sessionId", req.SessionID),
+		zap.String("uri", req.URI),
+		zap.Int("items", len(resp.Items)),
+	)
 
 	sendWSResponse(conn, writeMu, wsCompletionResponse{
 		ID:           req.ID,