corrected few nits

accessors/spanner/spannermetadataaccessor/clients/spanner_metadata_client.go

@@ -33,7 +33,7 @@ func GetOrCreateClient(ctx context.Context, dbURI string) (*sp.Client, error) {
 			spannermetadataClient, err = newClient(ctx, dbURI)
 		})
 		if err != nil {
-			return nil, fmt.Errorf("failed to create spanner database client: %v", err)
+			return nil, fmt.Errorf("failed to create spanner metadata database client: %v", err)
 		}
 		return spannermetadataClient, nil
 	}

accessors/spanner/spannermetadataaccessor/clients/spanner_metadata_client_test.go

@@ -49,8 +49,8 @@ func TestGetOrCreateClient_Basic(t *testing.T) {
 	newClient = func(ctx context.Context, database string, opts ...option.ClientOption) (*sp.Client, error) {
 		return &sp.Client{}, nil
 	}
-	c, err := GetOrCreateClient(ctx, "testURI")
-	assert.NotNil(t, c)
+	client, err := GetOrCreateClient(ctx, "testURI")
+	assert.NotNil(t, client)
 	assert.Nil(t, err)
 }
 
@@ -63,17 +63,17 @@ func TestGetOrCreateClient_OnlyOnceViaSync(t *testing.T) {
 	newClient = func(ctx context.Context, database string, opts ...option.ClientOption) (*sp.Client, error) {
 		return &sp.Client{}, nil
 	}
-	c, err := GetOrCreateClient(ctx, "testURI")
-	assert.NotNil(t, c)
+	client, err := GetOrCreateClient(ctx, "testURI")
+	assert.NotNil(t, client)
 	assert.Nil(t, err)
 	// Explicitly set the client to nil. Running GetOrCreateClient should not create a
 	// new client since sync would already be executed.
 	spannermetadataClient = nil
 	newClient = func(ctx context.Context, database string, opts ...option.ClientOption) (*sp.Client, error) {
 		return nil, fmt.Errorf("test error")
 	}
-	c, err = GetOrCreateClient(ctx, "testURI")
-	assert.Nil(t, c)
+	client, err = GetOrCreateClient(ctx, "testURI")
+	assert.Nil(t, client)
 	assert.Nil(t, err)
 }
 
@@ -110,7 +110,7 @@ func TestGetOrCreateClient_Error(t *testing.T) {
 	newClient = func(ctx context.Context, database string, opts ...option.ClientOption) (*sp.Client, error) {
 		return nil, fmt.Errorf("test error")
 	}
-	c, err := GetOrCreateClient(ctx, "testURI")
-	assert.Nil(t, c)
+	client, err := GetOrCreateClient(ctx, "testURI")
+	assert.Nil(t, client)
 	assert.NotNil(t, err)
 }

accessors/spanner/spannermetadataaccessor/spanner_metadata_accessor.go

@@ -24,16 +24,16 @@ import (
 )
 
 type SpannerMetadataAccessor interface {
-	// IsSpannerSupportedStatement checks whether the statement from Source database is supported by Spanner or not.
+	// IsSpannerSupportedStatement checks if the given statement is supported by Spanner.
 	IsSpannerSupportedStatement(SpProjectId string, SpInstanceId string, statement string, columntype string) bool
-	// isValidSpannerStatement fires query to spanner to cast statement based on spanner column type.
-	isValidSpannerStatement(db string, defaultval string, ty string) error
+	// isValidSpannerStatement queries spanner and checks if statement evaluates to a data corresponding to given type.
+	isValidSpannerStatement(db string, defaultval string, datatype string) error
 }
 
 type SpannerMetadataAccessorImpl struct{}
 
 func (spm *SpannerMetadataAccessorImpl) IsSpannerSupportedStatement(SpProjectId string, SpInstanceId string, statement string, columntype string) bool {
-	db := getSpannerUri(SpProjectId, SpInstanceId)
+	db := getSpannerMetadataDbUri(SpProjectId, SpInstanceId)
 	if SpProjectId == "" || SpInstanceId == "" {
 		return false
 	}
@@ -44,18 +44,18 @@ func (spm *SpannerMetadataAccessorImpl) IsSpannerSupportedStatement(SpProjectId
 		return true
 	}
 }
-func (spm *SpannerMetadataAccessorImpl) isValidSpannerStatement(db string, statement string, ty string) error {
+func (spm *SpannerMetadataAccessorImpl) isValidSpannerStatement(db string, statement string, datatype string) error {
 	ctx := context.Background()
 	spmClient, err := spannermetadataclient.GetOrCreateClient(ctx, db)
 	if err != nil {
 		return err
 	}
 
 	if spmClient == nil {
-		return fmt.Errorf("Client is nil")
+		return fmt.Errorf("spannerMetadataClient is nil")
 	}
 	stmt := spanner.Statement{
-		SQL: "SELECT CAST(" + statement + " AS " + ty + ") AS ConvertedDefaultval",
+		SQL: "SELECT CAST(" + statement + " AS " + datatype + ") AS statementValue",
 	}
 	iter := spmClient.Single().Query(ctx, stmt)
 	defer iter.Stop()
@@ -71,6 +71,6 @@ func (spm *SpannerMetadataAccessorImpl) isValidSpannerStatement(db string, state
 	}
 }
 
-func getSpannerUri(projectId string, instanceId string) string {
+func getSpannerMetadataDbUri(projectId string, instanceId string) string {
 	return fmt.Sprintf("projects/%s/instances/%s/databases/%s", projectId, instanceId, constants.METADATA_DB)
 }

sources/common/toddl.go

@@ -147,14 +147,17 @@ func (ss *SchemaToSpannerImpl) SchemaToSpannerDDLHelper(SpProjectId string, SpIn
 		}
 
 		defaultVal := ddl.DefaultValue{
-			IsPresent: srcCol.DefaultValue.IsPresent,
-			Value:     srcCol.DefaultValue.Value,
+			IsPresent: false,
+			Value:     "",
 		}
 
 		if srcCol.DefaultValue.IsPresent {
 			spM := spannermetadataaccessor.SpannerMetadataAccessorImpl{}
 			defaultVal.IsPresent = spM.IsSpannerSupportedStatement(SpProjectId, SpInstanceId, srcCol.DefaultValue.Value, ty.Name)
 		}
+		if defaultVal.IsPresent {
+			defaultVal.Value = srcCol.DefaultValue.Value
+		}
 
 		spColDef[srcColId] = ddl.ColumnDef{
 			Name:         colName,

spanner/ddl/ast.go

@@ -249,7 +249,7 @@ func (cd ColumnDef) PrintColumnDef(c Config) (string, string) {
 			s += " NOT NULL "
 		}
 		if cd.DefaultValue.IsPresent {
-			s += " DEFAULT (" + cd.DefaultValue.Value + ") "
+			s += " DEFAULT (CAST(" + (cd.DefaultValue.Value) + " as " +(cd.T.Name)+ ")) "
 		}
 		s += cd.AutoGen.PrintAutoGenCol()
 	}