fix(api): downgrade client cancellation from error to warning

When a client disconnects (user cancel or LB timeout), the request
context is canceled. Previously this was logged at Error level and
marked as an error span in OTEL traces, creating noise alongside
real server errors.

Now context.Canceled is detected in both the logging middleware and
the OTEL tracing middleware: log level is downgraded to Warn and
the span gets a client.canceled attribute instead of an error status.

Author: dobrac

packages/api/internal/middleware/otel/tracing/middleware.go

@@ -18,6 +18,7 @@ package tracing // import "go.opentelemetry.io/contrib/instrumentation/github.co
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"strings"
 	"time"
@@ -112,9 +113,15 @@ func Middleware(tracerProvider oteltrace.TracerProvider, service string) gin.Han
 
 		status := c.Writer.Status()
 		attrs := semconv.HTTPAttributesFromHTTPStatusCode(status)
-		spanStatus, spanMessage := semconv.SpanStatusFromHTTPStatusCode(status)
 		span.SetAttributes(attrs...)
-		span.SetStatus(spanStatus, spanMessage)
+
+		if errors.Is(ctx.Err(), context.Canceled) {
+			span.SetAttributes(attribute.Bool("client.canceled", true))
+		} else {
+			spanStatus, spanMessage := semconv.SpanStatusFromHTTPStatusCode(status)
+			span.SetStatus(spanStatus, spanMessage)
+		}
+
 		if len(c.Errors) > 0 {
 			span.SetAttributes(attribute.String("gin.errors", strings.TrimSpace(c.Errors.String())))
 		}

packages/shared/pkg/middleware/logging.go

@@ -1,6 +1,7 @@
 package middleware
 
 import (
+	"context"
 	"errors"
 	"net/http"
 	"regexp"
@@ -100,9 +101,10 @@ func LoggingMiddleware(logger logger.Logger, conf Config) gin.HandlerFunc {
 			}
 
 			level := conf.DefaultLevel
-			if status >= http.StatusInternalServerError {
+			switch {
+			case status >= http.StatusInternalServerError && !errors.Is(ctx.Err(), context.Canceled):
 				level = zapcore.ErrorLevel
-			} else if status >= http.StatusBadRequest {
+			case status >= http.StatusBadRequest || errors.Is(ctx.Err(), context.Canceled):
 				level = zapcore.WarnLevel
 			}