feat(otelgin): enhance gin error tracking with span recording

CHANGELOG.md

@@ -13,6 +13,10 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 - Added support for providing `endpoint`, `pollingIntervalMs` and `initialSamplingRate` using environment variable `OTEL_TRACES_SAMPLER_ARG` in `go.opentelemetry.io/contrib/samples/jaegerremote`. (#6310)
 - Added support exporting logs via OTLP over gRPC in `go.opentelemetry.io/contrib/config`. (#6340)
 
+### Changed
+
+- Record an error instead of setting the `gin.errors` attribute in `go.opentelemetry.io/contrib/instrumentation/github.com/gin-gonic/gin/otelgin`. (#6346)
+
 ### Fixed
 
 - Fixed the value for configuring the OTLP exporter to use `grpc` instead of `grpc/protobuf` in `go.opentelemetry.io/contrib/config`. (#6338)

instrumentation/github.com/gin-gonic/gin/otelgin/gintrace.go

@@ -6,17 +6,19 @@
 package otelgin // import "go.opentelemetry.io/contrib/instrumentation/github.com/gin-gonic/gin/otelgin"
 
 import (
+	"errors"
 	"fmt"
 
 	"github.com/gin-gonic/gin"
 
-	"go.opentelemetry.io/contrib/instrumentation/github.com/gin-gonic/gin/otelgin/internal/semconvutil"
 	"go.opentelemetry.io/otel"
 	"go.opentelemetry.io/otel/attribute"
 	"go.opentelemetry.io/otel/codes"
 	"go.opentelemetry.io/otel/propagation"
 	semconv "go.opentelemetry.io/otel/semconv/v1.20.0"
 	oteltrace "go.opentelemetry.io/otel/trace"
+
+	"go.opentelemetry.io/contrib/instrumentation/github.com/gin-gonic/gin/otelgin/internal/semconvutil"
 )
 
 const (
@@ -95,7 +97,7 @@ func Middleware(service string, opts ...Option) gin.HandlerFunc {
 			span.SetAttributes(semconv.HTTPStatusCode(status))
 		}
 		if len(c.Errors) > 0 {
-			span.SetAttributes(attribute.String("gin.errors", c.Errors.String()))
+			span.RecordError(errors.New(c.Errors.String()))
 		}
 	}
 }

instrumentation/github.com/gin-gonic/gin/otelgin/test/gintrace_test.go

@@ -17,14 +17,14 @@ import (
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 
-	"go.opentelemetry.io/contrib/instrumentation/github.com/gin-gonic/gin/otelgin"
 	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/attribute"
 	"go.opentelemetry.io/otel/codes"
 	sdktrace "go.opentelemetry.io/otel/sdk/trace"
 	"go.opentelemetry.io/otel/sdk/trace/tracetest"
-
-	"go.opentelemetry.io/otel/attribute"
 	oteltrace "go.opentelemetry.io/otel/trace"
+
+	"go.opentelemetry.io/contrib/instrumentation/github.com/gin-gonic/gin/otelgin"
 )
 
 func init() {
@@ -91,6 +91,7 @@ func TestTrace200(t *testing.T) {
 	assert.Contains(t, attr, attribute.Int("http.status_code", http.StatusOK))
 	assert.Contains(t, attr, attribute.String("http.method", "GET"))
 	assert.Contains(t, attr, attribute.String("http.route", "/user/:id"))
+	assert.Empty(t, span.Events())
 }
 
 func TestError(t *testing.T) {
@@ -120,7 +121,13 @@ func TestError(t *testing.T) {
 	attr := span.Attributes()
 	assert.Contains(t, attr, attribute.String("net.host.name", "foobar"))
 	assert.Contains(t, attr, attribute.Int("http.status_code", http.StatusInternalServerError))
-	assert.Contains(t, attr, attribute.String("gin.errors", "Error #01: oh no\n"))
+
+	// verify the error event
+	events := span.Events()
+	assert.Len(t, events, 1)
+	assert.Equal(t, "exception", events[0].Name)
+	assert.Contains(t, events[0].Attributes, attribute.String("exception.type", "*errors.errorString"))
+	assert.Contains(t, events[0].Attributes, attribute.String("exception.message", "Error #01: oh no\n"))
 	// server errors set the status
 	assert.Equal(t, codes.Error, span.Status().Code)
 }