fix(metrics): not report status code 200 when http client returns err…

…or (#50)

* remove status_code in metrics report when http client returns error and no response received

* add test case

* fix lint check

tracing/example_test.go

@@ -59,6 +59,10 @@ func TestMetricsExample(t *testing.T) {
 	require.NoError(t, err)
 	assert.NotNil(t, body)
 
+	// test client returns error
+	_, _, err = c.Get(context.Background(), nil, "http://localhost:39887/ping?foo=bar")
+	assert.NotNil(t, err)
+
 	// diff metrics
 	assert.NoError(t, testutil.GatherAndCompare(
 		registry, "testdata/hertz_request_metrics.txt",

tracing/middleware.go

@@ -18,16 +18,16 @@ import (
 	"context"
 	"time"
 
-	"github.com/cloudwego/hertz/pkg/common/tracer/stats"
-	"go.opentelemetry.io/otel/attribute"
-
 	"github.com/cloudwego/hertz/pkg/app"
 	"github.com/cloudwego/hertz/pkg/app/client"
 	"github.com/cloudwego/hertz/pkg/common/adaptor"
 	"github.com/cloudwego/hertz/pkg/common/hlog"
+	"github.com/cloudwego/hertz/pkg/common/tracer/stats"
 	"github.com/cloudwego/hertz/pkg/protocol"
 	"github.com/hertz-contrib/obs-opentelemetry/tracing/internal"
+	"go.opentelemetry.io/otel/attribute"
 	"go.opentelemetry.io/otel/baggage"
+	"go.opentelemetry.io/otel/codes"
 	"go.opentelemetry.io/otel/metric"
 	"go.opentelemetry.io/otel/sdk/trace"
 	semconv "go.opentelemetry.io/otel/semconv/v1.10.0"
@@ -104,12 +104,16 @@ func ClientMiddleware(opts ...Option) client.Middleware {
 			// span attributes
 			attrs := []attribute.KeyValue{
 				semconv.HTTPURLKey.String(req.URI().String()),
-				semconv.HTTPStatusCodeKey.Int(resp.StatusCode()),
 			}
-			span.SetAttributes(attrs...)
 
-			// set span status with resp status code
-			span.SetStatus(semconv.SpanStatusFromHTTPStatusCode(resp.StatusCode()))
+			if err == nil {
+				// set span status with resp status code
+				span.SetStatus(semconv.SpanStatusFromHTTPStatusCode(resp.StatusCode()))
+				attrs = append(attrs, semconv.HTTPStatusCodeKey.Int(resp.StatusCode()))
+			} else { // resp.StatusCode() is not valid when client returns error
+				span.SetStatus(codes.Error, err.Error())
+			}
+			span.SetAttributes(attrs...)
 
 			// extract metrics attr
 			metricsAttributes := extractMetricsAttributesFromSpan(span)

tracing/testdata/hertz_request_metrics.txt

@@ -1,5 +1,6 @@
 # HELP http_client_request_count_total measures the client request count total
 # TYPE http_client_request_count_total counter
+http_client_request_count_total{deployment_environment="test-env",http_host="localhost:39887",http_method="GET",http_route="/ping",otel_scope_name="github.com/hertz-contrib/obs-opentelemetry",otel_scope_version="semver:0.39.0",service_name="test-server",service_namespace="test-ns",status_code="Error"} 1
 http_client_request_count_total{deployment_environment="test-env",http_host="localhost:39888",http_method="GET",http_route="/ping",http_status_code="200",otel_scope_name="github.com/hertz-contrib/obs-opentelemetry",otel_scope_version="semver:0.39.0",service_name="test-server",service_namespace="test-ns",status_code="Unset"} 1
 # HELP http_server_request_count_total measures Incoming request count total
 # TYPE http_server_request_count_total counter