HTTP traced client panic (fixes #247)

Signed-off-by: Sotirios Mantziaris <[email protected]>

trace/http/http.go

@@ -7,7 +7,7 @@ import (
 
 	"github.com/mantzas/patron/trace"
 	"github.com/opentracing-contrib/go-stdlib/nethttp"
-	"github.com/opentracing/opentracing-go"
+	opentracing "github.com/opentracing/opentracing-go"
 	"github.com/opentracing/opentracing-go/ext"
 )
 
@@ -52,9 +52,10 @@ func (tc *TracedClient) Do(ctx context.Context, req *http.Request) (*http.Respon
 	rsp, err := tc.cl.Do(req)
 	if err != nil {
 		ext.Error.Set(ht.Span(), true)
+	} else {
+		ext.HTTPStatusCode.Set(ht.Span(), uint16(rsp.StatusCode))
 	}
 	ext.HTTPMethod.Set(ht.Span(), req.Method)
 	ext.HTTPUrl.Set(ht.Span(), req.URL.String())
-	ext.HTTPStatusCode.Set(ht.Span(), uint16(rsp.StatusCode))
 	return rsp, err
 }

trace/http/http_test.go

@@ -9,7 +9,7 @@ import (
 	"time"
 
 	"github.com/mantzas/patron/trace"
-	"github.com/opentracing/opentracing-go"
+	opentracing "github.com/opentracing/opentracing-go"
 	"github.com/opentracing/opentracing-go/mocktracer"
 	"github.com/stretchr/testify/assert"
 )
@@ -36,6 +36,28 @@ func TestTracedClient_Do(t *testing.T) {
 	assert.Equal(t, trace.HTTPOpName("Client", "GET", ts.URL), sp.OperationName)
 }
 
+func TestTracedClient_Do_Error(t *testing.T) {
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		assert.Equal(t, "true", r.Header.Get("Mockpfx-Ids-Sampled"))
+		assert.Equal(t, "46", r.Header.Get("Mockpfx-Ids-Spanid"))
+		assert.Equal(t, "43", r.Header.Get("Mockpfx-Ids-Traceid"))
+		fmt.Fprintln(w, "Hello, client")
+	}))
+	defer ts.Close()
+	mtr := mocktracer.New()
+	opentracing.SetGlobalTracer(mtr)
+	c, err := New()
+	assert.NoError(t, err)
+	req, err := http.NewRequest("GET", "", nil)
+	assert.NoError(t, err)
+	rsp, err := c.Do(context.Background(), req)
+	assert.Error(t, err)
+	assert.Nil(t, rsp)
+	sp := mtr.FinishedSpans()[0]
+	assert.NotNil(t, sp)
+	assert.Equal(t, "HTTP GET", sp.OperationName)
+}
+
 func TestNew(t *testing.T) {
 	type args struct {
 		opt OptionFunc