Add AllowedMethods field to transport.Options

to enable users to specify allowed HTTP methods.

graphql/handler/transport/options.go

@@ -2,12 +2,15 @@ package transport
 
 import (
 	"net/http"
+	"strings"
 
 	"github.com/99designs/gqlgen/graphql"
 )
 
 // Options responds to http OPTIONS and HEAD requests
-type Options struct{}
+type Options struct {
+	AllowedMethods []string
+}
 
 var _ graphql.Transport = Options{}
 
@@ -18,9 +21,16 @@ func (o Options) Supports(r *http.Request) bool {
 func (o Options) Do(w http.ResponseWriter, r *http.Request, exec graphql.GraphExecutor) {
 	switch r.Method {
 	case http.MethodOptions:
-		w.Header().Set("Allow", "OPTIONS, GET, POST")
+		w.Header().Set("Allow", o.allowedMethods())
 		w.WriteHeader(http.StatusOK)
 	case http.MethodHead:
 		w.WriteHeader(http.StatusMethodNotAllowed)
 	}
 }
+
+func (o Options) allowedMethods() string {
+	if o.AllowedMethods == nil {
+		return "OPTIONS, GET, POST"
+	}
+	return strings.Join(o.AllowedMethods, ", ")
+}

graphql/handler/transport/options_test.go

@@ -4,22 +4,34 @@ import (
 	"net/http"
 	"testing"
 
+	"github.com/stretchr/testify/assert"
+
 	"github.com/99designs/gqlgen/graphql/handler/testserver"
 	"github.com/99designs/gqlgen/graphql/handler/transport"
-	"github.com/stretchr/testify/assert"
 )
 
 func TestOptions(t *testing.T) {
-	h := testserver.New()
-	h.AddTransport(transport.Options{})
-
-	t.Run("responds to options requests", func(t *testing.T) {
+	t.Run("responds to options requests with default methods", func(t *testing.T) {
+		h := testserver.New()
+		h.AddTransport(transport.Options{})
 		resp := doRequest(h, "OPTIONS", "/graphql?query={me{name}}", ``)
 		assert.Equal(t, http.StatusOK, resp.Code)
 		assert.Equal(t, "OPTIONS, GET, POST", resp.Header().Get("Allow"))
 	})
 
+	t.Run("responds to options requests with specified methods", func(t *testing.T) {
+		h := testserver.New()
+		h.AddTransport(transport.Options{
+			AllowedMethods: []string{http.MethodOptions, http.MethodPost, http.MethodHead},
+		})
+		resp := doRequest(h, "OPTIONS", "/graphql?query={me{name}}", ``)
+		assert.Equal(t, http.StatusOK, resp.Code)
+		assert.Equal(t, "OPTIONS, POST, HEAD", resp.Header().Get("Allow"))
+	})
+
 	t.Run("responds to head requests", func(t *testing.T) {
+		h := testserver.New()
+		h.AddTransport(transport.Options{})
 		resp := doRequest(h, "HEAD", "/graphql?query={me{name}}", ``)
 		assert.Equal(t, http.StatusMethodNotAllowed, resp.Code)
 	})