feat(logging): scope request ID tracking to AI API endpoints

internal/logging/gin_logger.go

@@ -7,6 +7,7 @@ import (
 	"fmt"
 	"net/http"
 	"runtime/debug"
+	"strings"
 	"time"
 
 	"github.com/gin-gonic/gin"
@@ -14,28 +15,42 @@ import (
 	log "github.com/sirupsen/logrus"
 )
 
+// aiAPIPrefixes defines path prefixes for AI API requests that should have request ID tracking.
+var aiAPIPrefixes = []string{
+	"/v1/chat/completions",
+	"/v1/completions",
+	"/v1/messages",
+	"/v1/responses",
+	"/v1beta/models/",
+	"/api/provider/",
+}
+
 const skipGinLogKey = "__gin_skip_request_logging__"
 
 // GinLogrusLogger returns a Gin middleware handler that logs HTTP requests and responses
 // using logrus. It captures request details including method, path, status code, latency,
-// client IP, and any error messages, formatted with request ID for correlation.
+// client IP, and any error messages. Request ID is only added for AI API requests.
 //
-// Output format: [2025-12-23 20:14:10] [info ] [a1b2c3d4] 200 |       23.559s |  144.34.236.116 | POST    "/v1/messages?beta=true"
+// Output format (AI API): [2025-12-23 20:14:10] [info ] | a1b2c3d4 | 200 |       23.559s | ...
+// Output format (others): [2025-12-23 20:14:10] [info ] | -------- | 200 |       23.559s | ...
 //
 // Returns:
 //   - gin.HandlerFunc: A middleware handler for request logging
 func GinLogrusLogger() gin.HandlerFunc {
 	return func(c *gin.Context) {
-		requestID := GenerateRequestID()
-		SetGinRequestID(c, requestID)
-
-		ctx := WithRequestID(c.Request.Context(), requestID)
-		c.Request = c.Request.WithContext(ctx)
-
 		start := time.Now()
 		path := c.Request.URL.Path
 		raw := util.MaskSensitiveQuery(c.Request.URL.RawQuery)
 
+		// Only generate request ID for AI API paths
+		var requestID string
+		if isAIAPIPath(path) {
+			requestID = GenerateRequestID()
+			SetGinRequestID(c, requestID)
+			ctx := WithRequestID(c.Request.Context(), requestID)
+			c.Request = c.Request.WithContext(ctx)
+		}
+
 		c.Next()
 
 		if shouldSkipGinRequestLogging(c) {
@@ -63,7 +78,13 @@ func GinLogrusLogger() gin.HandlerFunc {
 			logLine = logLine + " | " + errorMessage
 		}
 
-		entry := log.WithField("request_id", requestID)
+		var entry *log.Entry
+		if requestID != "" {
+			entry = log.WithField("request_id", requestID)
+		} else {
+			entry = log.WithField("request_id", "--------")
+		}
+
 		switch {
 		case statusCode >= http.StatusInternalServerError:
 			entry.Error(logLine)
@@ -75,6 +96,16 @@ func GinLogrusLogger() gin.HandlerFunc {
 	}
 }
 
+// isAIAPIPath checks if the given path is an AI API endpoint that should have request ID tracking.
+func isAIAPIPath(path string) bool {
+	for _, prefix := range aiAPIPrefixes {
+		if strings.HasPrefix(path, prefix) {
+			return true
+		}
+	}
+	return false
+}
+
 // GinLogrusRecovery returns a Gin middleware handler that recovers from panics and logs
 // them using logrus. When a panic occurs, it captures the panic value, stack trace,
 // and request path, then returns a 500 Internal Server Error response to the client.