From 34980fac0b6ccf07950addbe8dfb7f755031d36e Mon Sep 17 00:00:00 2001
From: Dien Vo <163492606+dienvoandpadcojp@users.noreply.github.com>
Date: Fri, 27 Sep 2024 15:52:24 +0700
Subject: [PATCH] contrib/99designs/gqlgen/tracer.go: nil check response
 (#2792)

---
 contrib/99designs/gqlgen/tracer.go      | 23 ++++---
 contrib/99designs/gqlgen/tracer_test.go | 88 +++++++++++++++++++++++++
 2 files changed, 103 insertions(+), 8 deletions(-)

diff --git a/contrib/99designs/gqlgen/tracer.go b/contrib/99designs/gqlgen/tracer.go
index 66b0208c362..ffdcb0c5501 100644
--- a/contrib/99designs/gqlgen/tracer.go
+++ b/contrib/99designs/gqlgen/tracer.go
@@ -123,14 +123,21 @@ func (t *gqlTracer) InterceptOperation(ctx context.Context, next graphql.Operati
 			}
 			defer span.Finish(tracer.WithError(err))
 		}
-		query.Finish(graphqlsec.ExecutionOperationRes{
-			Data:  response.Data, // NB - This is raw data, but rather not parse it (possibly expensive).
-			Error: response.Errors,
-		})
-		req.Finish(span, graphqlsec.RequestOperationRes{
-			Data:  response.Data, // NB - This is raw data, but rather not parse it (possibly expensive).
-			Error: response.Errors,
-		})
+
+		var (
+			executionOperationRes graphqlsec.ExecutionOperationRes
+			requestOperationRes   graphqlsec.RequestOperationRes
+		)
+		if response != nil {
+			executionOperationRes.Data = response.Data
+			executionOperationRes.Error = response.Errors
+
+			requestOperationRes.Data = response.Data
+			requestOperationRes.Error = response.Errors
+		}
+
+		query.Finish(executionOperationRes)
+		req.Finish(span, requestOperationRes)
 		return response
 	}
 }
diff --git a/contrib/99designs/gqlgen/tracer_test.go b/contrib/99designs/gqlgen/tracer_test.go
index 0517aef9762..09e6eab6288 100644
--- a/contrib/99designs/gqlgen/tracer_test.go
+++ b/contrib/99designs/gqlgen/tracer_test.go
@@ -261,3 +261,91 @@ func newTestClient(t *testing.T, h *testserver.TestServer, tracer graphql.Handle
 	h.Use(tracer)
 	return client.New(h)
 }
+
+func TestInterceptOperation(t *testing.T) {
+	assertions := assert.New(t)
+	graphqlTestSrv := testserver.New()
+	c := newTestClient(t, graphqlTestSrv, NewTracer())
+
+	t.Run("intercept operation with graphQL Query", func(t *testing.T) {
+		mt := mocktracer.Start()
+		defer mt.Stop()
+
+		err := c.Post(`{ name }`, &testServerResponse{})
+		assertions.Nil(err)
+
+		allSpans := mt.FinishedSpans()
+		var root mocktracer.Span
+		var resNames []string
+		var opNames []string
+		for _, span := range allSpans {
+			if span.ParentID() == 0 {
+				root = span
+			}
+			resNames = append(resNames, span.Tag(ext.ResourceName).(string))
+			opNames = append(opNames, span.OperationName())
+			assertions.Equal("99designs/gqlgen", span.Tag(ext.Component))
+		}
+		assertions.ElementsMatch(resNames, []string{readOp, parsingOp, validationOp, "Query.name", `{ name }`})
+		assertions.ElementsMatch(opNames, []string{readOp, parsingOp, validationOp, fieldOp, "graphql.query"})
+		assertions.NotNil(root)
+		assertions.Nil(root.Tag(ext.Error))
+	})
+
+	t.Run("intercept operation with graphQL Mutation", func(t *testing.T) {
+		mt := mocktracer.Start()
+		defer mt.Stop()
+
+		err := c.Post(`mutation Name { name }`, &testServerResponse{})
+		// due to testserver.New() implementation, mutation is not supported
+		assertions.NotNil(err)
+
+		allSpans := mt.FinishedSpans()
+		var root mocktracer.Span
+		var resNames []string
+		var opNames []string
+		for _, span := range allSpans {
+			if span.ParentID() == 0 {
+				root = span
+			}
+			resNames = append(resNames, span.Tag(ext.ResourceName).(string))
+			opNames = append(opNames, span.OperationName())
+			assertions.Equal("99designs/gqlgen", span.Tag(ext.Component))
+		}
+		assertions.ElementsMatch(resNames, []string{readOp, parsingOp, validationOp, `mutation Name { name }`})
+		assertions.ElementsMatch(opNames, []string{readOp, parsingOp, validationOp, "graphql.mutation"})
+		assertions.NotNil(root)
+		assertions.NotNil(root.Tag(ext.Error))
+	})
+
+	t.Run("intercept operation with graphQL Subscription", func(t *testing.T) {
+		mt := mocktracer.Start()
+		defer mt.Stop()
+
+		go func() {
+			graphqlTestSrv.SendCompleteSubscriptionMessage()
+		}()
+
+		// using raw post because post try to access nil response's Data field
+		resp, err := c.RawPost(`subscription Name { name }`)
+		assertions.Nil(err)
+		assertions.Nil(resp)
+
+		allSpans := mt.FinishedSpans()
+		var root mocktracer.Span
+		var resNames []string
+		var opNames []string
+		for _, span := range allSpans {
+			if span.ParentID() == 0 {
+				root = span
+			}
+			resNames = append(resNames, span.Tag(ext.ResourceName).(string))
+			opNames = append(opNames, span.OperationName())
+			assertions.Equal("99designs/gqlgen", span.Tag(ext.Component))
+		}
+		assertions.ElementsMatch(resNames, []string{`subscription Name { name }`, `subscription Name { name }`, "subscription Name { name }"})
+		assertions.ElementsMatch(opNames, []string{readOp, parsingOp, validationOp})
+		assertions.NotNil(root)
+		assertions.Nil(root.Tag(ext.Error))
+	})
+}