refactor(otelgin): refine span name formatting and deprecate `SpanNam…

…eFormatter` option

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

@@ -6,10 +6,11 @@
 package otelgin // import "go.opentelemetry.io/contrib/instrumentation/github.com/gin-gonic/gin/otelgin"
 
 import (
-	"fmt"
+	"net/http"
+	"slices"
+	"strings"
 
 	"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"
@@ -71,16 +72,7 @@ func Middleware(service string, opts ...Option) gin.HandlerFunc {
 			oteltrace.WithAttributes(semconv.HTTPRoute(c.FullPath())),
 			oteltrace.WithSpanKind(oteltrace.SpanKindServer),
 		}
-		var spanName string
-		if cfg.SpanNameFormatter == nil {
-			spanName = c.FullPath()
-		} else {
-			spanName = cfg.SpanNameFormatter(c.Request)
-		}
-		if spanName == "" {
-			spanName = fmt.Sprintf("HTTP %s route not found", c.Request.Method)
-		}
-		ctx, span := tracer.Start(ctx, spanName, opts...)
+		ctx, span := tracer.Start(ctx, spanNameFormatter(c), opts...)
 		defer span.End()
 
 		// pass the span through the request context
@@ -103,6 +95,26 @@ func Middleware(service string, opts ...Option) gin.HandlerFunc {
 	}
 }
 
+// spanNameFormatter is used to set span name by gin.Context.
+func spanNameFormatter(c *gin.Context) string {
+	method, path := strings.ToUpper(c.Request.Method), c.FullPath()
+	if !slices.Contains([]string{
+		http.MethodGet, http.MethodHead,
+		http.MethodPost, http.MethodPut,
+		http.MethodPatch, http.MethodDelete,
+		http.MethodConnect, http.MethodOptions,
+		http.MethodTrace,
+	}, method) {
+		method = "HTTP"
+	}
+
+	if path != "" {
+		return method + " " + path
+	}
+
+	return method
+}
+
 // HTML will trace the rendering of the template as a child of the
 // span in the given context. This is a replacement for
 // gin.Context.HTML function - it invokes the original function after

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

@@ -19,7 +19,7 @@ type config struct {
 	Propagators       propagation.TextMapPropagator
 	Filters           []Filter
 	GinFilters        []GinFilter
-	SpanNameFormatter SpanNameFormatter
+	SpanNameFormatter SpanNameFormatter // Deprecated: since 0.58.0, remove in 0.59.0.
 }
 
 // Filter is a predicate used to determine whether a given http.request should
@@ -31,6 +31,7 @@ type Filter func(*http.Request) bool
 type GinFilter func(*gin.Context) bool
 
 // SpanNameFormatter is used to set span name by http.request.
+// Deprecated: since 0.58.0, remove in 0.59.0.
 type SpanNameFormatter func(r *http.Request) string
 
 // Option specifies instrumentation configuration options.
@@ -86,8 +87,7 @@ func WithGinFilter(f ...GinFilter) Option {
 
 // WithSpanNameFormatter takes a function that will be called on every
 // request and the returned string will become the Span Name.
-func WithSpanNameFormatter(f func(r *http.Request) string) Option {
-	return optionFunc(func(c *config) {
-		c.SpanNameFormatter = f
-	})
+// Deprecated: since 0.58.0, remove in 0.59.0.
+func WithSpanNameFormatter(func(r *http.Request) string) Option {
+	return optionFunc(func(*config) {})
 }

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

@@ -157,7 +157,7 @@ func TestTrace200(t *testing.T) {
 	spans := sr.Ended()
 	require.Len(t, spans, 1)
 	span := spans[0]
-	assert.Equal(t, "/user/:id", span.Name())
+	assert.Equal(t, "GET /user/:id", span.Name())
 	assert.Equal(t, trace.SpanKindServer, span.SpanKind())
 	attr := span.Attributes()
 	assert.Contains(t, attr, attribute.String("net.host.name", "foobar"))
@@ -193,7 +193,7 @@ func TestError(t *testing.T) {
 	spans := sr.Ended()
 	require.Len(t, spans, 1)
 	span := spans[0]
-	assert.Equal(t, "/server_err", span.Name())
+	assert.Equal(t, "GET /server_err", span.Name())
 	attr := span.Attributes()
 	assert.Contains(t, attr, attribute.String("net.host.name", "foobar"))
 	assert.Contains(t, attr, attribute.Int("http.status_code", http.StatusInternalServerError))
@@ -268,8 +268,8 @@ func TestSpanName(t *testing.T) {
 		spanNameFormatter otelgin.SpanNameFormatter
 		wantSpanName      string
 	}{
-		{"/user/1", nil, "/user/:id"},
-		{"/user/1", func(r *http.Request) string { return r.URL.Path }, "/user/1"},
+		{"/user/1", nil, "GET /user/:id"},
+		{"/user/1", func(r *http.Request) string { return r.URL.Path }, "GET /user/:id"},
 	}
 	for _, tc := range testCases {
 		t.Run(tc.requestPath, func(t *testing.T) {
@@ -317,7 +317,7 @@ func TestHTTPRouteWithSpanNameFormatter(t *testing.T) {
 	spans := sr.Ended()
 	require.Len(t, spans, 1)
 	span := spans[0]
-	assert.Equal(t, "/user/123", span.Name())
+	assert.Equal(t, "GET /user/:id", span.Name())
 	assert.Equal(t, trace.SpanKindServer, span.SpanKind())
 	attr := span.Attributes()
 	assert.Contains(t, attr, attribute.String("http.method", "GET"))