Minor changes from self review

Signed-off-by: Matt Lord <[email protected]>

go/vt/vtctl/workflow/materializer_env_test.go

@@ -244,6 +244,8 @@ func newTestMaterializerTMClient(keyspace string, sourceShards []string, tableSe
 }
 
 func (tmc *testMaterializerTMClient) CreateVReplicationWorkflow(ctx context.Context, tablet *topodatapb.Tablet, request *tabletmanagerdatapb.CreateVReplicationWorkflowRequest) (*tabletmanagerdatapb.CreateVReplicationWorkflowResponse, error) {
+	tmc.mu.Lock()
+	defer tmc.mu.Unlock()
 	if expect := tmc.createVReplicationWorkflowRequests[tablet.Alias.Uid]; expect != nil {
 		if expect.req != nil && !proto.Equal(expect.req, request) {
 			return nil, vterrors.Errorf(vtrpcpb.Code_INVALID_ARGUMENT, "unexpected CreateVReplicationWorkflow request: got %+v, want %+v", request, expect)
@@ -257,6 +259,9 @@ func (tmc *testMaterializerTMClient) CreateVReplicationWorkflow(ctx context.Cont
 }
 
 func (tmc *testMaterializerTMClient) ReadVReplicationWorkflow(ctx context.Context, tablet *topodatapb.Tablet, request *tabletmanagerdatapb.ReadVReplicationWorkflowRequest) (*tabletmanagerdatapb.ReadVReplicationWorkflowResponse, error) {
+	tmc.mu.Lock()
+	defer tmc.mu.Unlock()
+
 	if tmc.readVReplicationWorkflow != nil {
 		return tmc.readVReplicationWorkflow(ctx, tablet, request)
 	}
@@ -310,6 +315,9 @@ func (tmc *testMaterializerTMClient) DeleteVReplicationWorkflow(ctx context.Cont
 }
 
 func (tmc *testMaterializerTMClient) GetSchema(ctx context.Context, tablet *topodatapb.Tablet, request *tabletmanagerdatapb.GetSchemaRequest) (*tabletmanagerdatapb.SchemaDefinition, error) {
+	tmc.mu.Lock()
+	defer tmc.mu.Unlock()
+
 	schemaDefn := &tabletmanagerdatapb.SchemaDefinition{}
 	for _, table := range request.Tables {
 		if table == "/.*/" {
@@ -430,6 +438,9 @@ func (tmc *testMaterializerTMClient) HasVReplicationWorkflows(ctx context.Contex
 }
 
 func (tmc *testMaterializerTMClient) ReadVReplicationWorkflows(ctx context.Context, tablet *topodatapb.Tablet, req *tabletmanagerdatapb.ReadVReplicationWorkflowsRequest) (*tabletmanagerdatapb.ReadVReplicationWorkflowsResponse, error) {
+	tmc.mu.Lock()
+	defer tmc.mu.Unlock()
+
 	workflowType := binlogdatapb.VReplicationWorkflowType_MoveTables
 	if len(req.IncludeWorkflows) > 0 {
 		for _, wf := range req.IncludeWorkflows {

go/vt/vtctl/workflow/materializer_test.go

@@ -1667,7 +1667,7 @@ func TestCreateLookupVindexTargetVSchema(t *testing.T) {
 		}
 		require.NoError(t, err)
 		// withTable is a vschema that already contains the table and thus
-		// we make not vschema changes and there's nothing to cancel.
+		// we don't make any vschema changes and there's nothing to cancel.
 		require.True(t, (cancelFunc != nil) == (tcase.targetVSchema != withTable))
 		utils.MustMatch(t, tcase.out, got, tcase.description)
 	}
@@ -2463,7 +2463,7 @@ func TestCreateLookupVindexFailures(t *testing.T) {
 			},
 			vrepExecQueries: []string{"CREATE TABLE `t1_lkp` (\n`c1` INT,\n  `keyspace_id` varbinary(128),\n  PRIMARY KEY (`c1`)\n)"},
 			createRequest: &createVReplicationWorkflowRequestResponse{
-				req: nil,
+				req: nil, // We don't care about defining it in this case
 				res: &tabletmanagerdatapb.CreateVReplicationWorkflowResponse{},
 				err: errors.New("we gots us an error"),
 			},

go/vt/vtctl/workflow/server.go

@@ -1139,7 +1139,8 @@ func (s *Server) LookupVindexCreate(ctx context.Context, req *vtctldatapb.Lookup
 	}
 
 	if err := s.ts.SaveVSchema(ctx, ms.TargetKeyspace, targetVSchema); err != nil {
-		return nil, err
+		return nil, vterrors.Wrapf(err, "failed to save updated vschema '%v' in the %s keyspace",
+			targetVSchema, ms.TargetKeyspace)
 	}
 	ms.TabletTypes = topoproto.MakeStringTypeCSV(req.TabletTypes)
 	ms.TabletSelectionPreference = req.TabletSelectionPreference
@@ -4146,6 +4147,8 @@ func (s *Server) prepareCreateLookup(ctx context.Context, workflow, keyspace str
 	}
 	materializeQuery = buf.String()
 
+	// Save a copy of the original vschema if we modify it and need to provide
+	// a cancelFunc.
 	ogTargetVSchema := targetVSchema.CloneVT()
 	targetChanged := false