fix: ensure that apq alone (without persistent operations enabled) wo…

…rks (#1402)

router-tests/automatic_persisted_queries_test.go

@@ -23,6 +23,9 @@ func TestAutomaticPersistedQueries(t *testing.T) {
 
 		t.Run("Sha without query fails", func(t *testing.T) {
 			testenv.Run(t, &testenv.Config{
+				RouterOptions: []core.Option{
+					core.WithGraphApiToken(""),
+				},
 				ApqConfig: config.AutomaticPersistedQueriesConfig{
 					Enabled: true,
 				},
@@ -36,6 +39,11 @@ func TestAutomaticPersistedQueries(t *testing.T) {
 
 		t.Run("Sha with query works", func(t *testing.T) {
 			testenv.Run(t, &testenv.Config{
+				RouterOptions: []core.Option{
+					// This ensures that no CDN client for persistent operations is created, so we can verify that
+					// APQ alone (without persistent operation support setup) works as expected.
+					core.WithGraphApiToken(""),
+				},
 				ApqConfig: config.AutomaticPersistedQueriesConfig{
 					Enabled: true,
 					Cache: config.AutomaticPersistedQueriesCacheConfig{

router/internal/persistedoperation/client.go

@@ -78,6 +78,11 @@ func (c client) PersistedOperation(ctx context.Context, clientName string, sha25
 		return data, false, nil
 	}
 
+	if c.providerClient == nil {
+		// This can happen if we are using APQ client, without any persisted operation client. Otherwise, we should have a provider client and shouldn't reach here.
+		return nil, c.apqClient != nil, nil
+	}
+
 	content, _, err := c.providerClient.PersistedOperation(ctx, clientName, sha256Hash)
 	if errors.As(err, &PoNotFoundErr) && c.apqClient != nil {
 		// This could well be the first time a client is requesting an APQ operation and the query is attached to the request. Return without error here, and we'll verify the operation later.