Add ContextHandler API function to externally provided net/context.Context

handler.go

@@ -9,6 +9,7 @@ import (
 	"github.com/gorilla/schema"
 	"github.com/graphql-go/graphql"
 	"github.com/unrolled/render"
+	"golang.org/x/net/context"
 )
 
 const (
@@ -104,9 +105,9 @@ func getRequestOptions(r *http.Request) *requestOptions {
 	}
 }
 
-// ServeHTTP provides an entry point into executing graphQL queries
-func (h *Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
-
+// ContextHandler provides an entrypoint into executing graphQL queries with a
+// user-provided context.
+func (h *Handler) ContextHandler(ctx context.Context, w http.ResponseWriter, r *http.Request) {
 	// get query
 	opts := getRequestOptions(r)
 
@@ -116,13 +117,19 @@ func (h *Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 		RequestString:  opts.Query,
 		VariableValues: opts.Variables,
 		OperationName:  opts.OperationName,
+		Context:        ctx,
 	}
 	result := graphql.Do(params)
 
 	// render result
 	h.render.JSON(w, http.StatusOK, result)
 }
 
+// ServeHTTP provides an entrypoint into executing graphQL queries.
+func (h *Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	h.ContextHandler(context.Background(), w, r)
+}
+
 type Config struct {
 	Schema *graphql.Schema
 	Pretty bool

handler_test.go

@@ -14,6 +14,7 @@ import (
 	"github.com/graphql-go/graphql/testutil"
 	"github.com/graphql-go/handler"
 	"github.com/graphql-go/relay/examples/starwars" // TODO: remove this dependency
+	"golang.org/x/net/context"
 )
 
 func decodeResponse(t *testing.T, recorder *httptest.ResponseRecorder) *graphql.Result {
@@ -39,6 +40,49 @@ func executeTest(t *testing.T, h *handler.Handler, req *http.Request) (*graphql.
 	return result, resp
 }
 
+func TestContextPropagated(t *testing.T) {
+	myNameQuery := graphql.NewObject(graphql.ObjectConfig{
+		Name: "Query",
+		Fields: graphql.Fields{
+			"name": &graphql.Field{
+				Name: "name",
+				Type: graphql.String,
+				Resolve: func(p graphql.ResolveParams) (interface{}, error) {
+					return p.Context.Value("name"), nil
+				},
+			},
+		},
+	})
+	myNameSchema, err := graphql.NewSchema(graphql.SchemaConfig{myNameQuery, nil})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	expected := &graphql.Result{
+		Data: map[string]interface{}{
+			"name": "context-data",
+		},
+	}
+	queryString := `query={name}`
+	req, _ := http.NewRequest("GET", fmt.Sprintf("/graphql?%v", queryString), nil)
+
+	h := handler.New(&handler.Config{
+		Schema: &myNameSchema,
+		Pretty: true,
+	})
+
+	ctx := context.WithValue(context.Background(), "name", "context-data")
+	resp := httptest.NewRecorder()
+	h.ContextHandler(ctx, resp, req)
+	result := decodeResponse(t, resp)
+	if resp.Code != http.StatusOK {
+		t.Fatalf("unexpected server response %v", resp.Code)
+	}
+	if !reflect.DeepEqual(result, expected) {
+		t.Fatalf("wrong result, graphql result diff: %v", testutil.Diff(expected, result))
+	}
+}
+
 func TestHandler_BasicQuery(t *testing.T) {
 
 	expected := &graphql.Result{