check for partition being synced before starting errgroup

flow/activities/flowable.go

@@ -611,12 +611,6 @@ func (a *FlowableActivity) replicateQRepPartition(ctx context.Context,
 	ctx = context.WithValue(ctx, shared.FlowNameKey, config.FlowJobName)
 	logger := activity.GetLogger(ctx)
 
-	err := monitoring.UpdateStartTimeForPartition(ctx, a.CatalogPool, runUUID, partition, time.Now())
-	if err != nil {
-		a.Alerter.LogFlowError(ctx, config.FlowJobName, err)
-		return fmt.Errorf("failed to update start time for partition: %w", err)
-	}
-
 	srcConn, err := connectors.GetQRepPullConnector(ctx, config.SourcePeer)
 	if err != nil {
 		a.Alerter.LogFlowError(ctx, config.FlowJobName, err)
@@ -631,6 +625,25 @@ func (a *FlowableActivity) replicateQRepPartition(ctx context.Context,
 	}
 	defer connectors.CloseConnector(ctx, dstConn)
 
+	done, err := dstConn.IsQRepPartitionSynced(ctx, &protos.IsQRepPartitionSyncedInput{
+		FlowJobName: config.FlowJobName,
+		PartitionId: partition.PartitionId,
+	})
+	if err != nil {
+		a.Alerter.LogFlowError(ctx, config.FlowJobName, err)
+		return fmt.Errorf("failed to get fetch status of partition: %w", err)
+	}
+	if done {
+		logger.Info("no records to push for partition " + partition.PartitionId)
+		return nil
+	}
+
+	err = monitoring.UpdateStartTimeForPartition(ctx, a.CatalogPool, runUUID, partition, time.Now())
+	if err != nil {
+		a.Alerter.LogFlowError(ctx, config.FlowJobName, err)
+		return fmt.Errorf("failed to update start time for partition: %w", err)
+	}
+
 	logger.Info("replicating partition " + partition.PartitionId)
 	shutdown := utils.HeartbeatRoutine(ctx, func() string {
 		return fmt.Sprintf("syncing partition - %s: %d of %d total.", partition.PartitionId, idx, total)
@@ -705,8 +718,6 @@ func (a *FlowableActivity) replicateQRepPartition(ctx context.Context,
 		if err != nil {
 			return err
 		}
-	} else {
-		logger.Info("no records to push for partition " + partition.PartitionId)
 	}
 
 	err = monitoring.UpdateEndTimeForPartition(ctx, a.CatalogPool, runUUID, partition)

flow/connectors/bigquery/qrep.go

@@ -30,15 +30,6 @@ func (c *BigQueryConnector) SyncQRepRecords(
 		return 0, err
 	}
 
-	done, err := c.pgMetadata.IsQrepPartitionSynced(ctx, config.FlowJobName, partition.PartitionId)
-	if err != nil {
-		return 0, fmt.Errorf("failed to check if partition %s is synced: %w", partition.PartitionId, err)
-	}
-
-	if done {
-		c.logger.Info(fmt.Sprintf("Partition %s has already been synced", partition.PartitionId))
-		return 0, nil
-	}
 	c.logger.Info(fmt.Sprintf("QRep sync function called and partition existence checked for"+
 		" partition %s of destination table %s",
 		partition.PartitionId, destTable))
@@ -111,3 +102,9 @@ func (c *BigQueryConnector) SetupQRepMetadataTables(ctx context.Context, config
 
 	return nil
 }
+
+func (c *BigQueryConnector) IsQRepPartitionSynced(ctx context.Context,
+	req *protos.IsQRepPartitionSyncedInput,
+) (bool, error) {
+	return c.pgMetadata.IsQrepPartitionSynced(ctx, req.FlowJobName, req.PartitionId)
+}

flow/connectors/clickhouse/qrep.go

@@ -33,16 +33,6 @@ func (c *ClickhouseConnector) SyncQRepRecords(
 		slog.String("destinationTable", destTable),
 	)
 
-	done, err := c.isPartitionSynced(ctx, partition.PartitionId)
-	if err != nil {
-		return 0, fmt.Errorf("failed to check if partition %s is synced: %w", partition.PartitionId, err)
-	}
-
-	if done {
-		c.logger.Info("Partition has already been synced", flowLog)
-		return 0, nil
-	}
-
 	tblSchema, err := c.getTableSchema(destTable)
 	if err != nil {
 		return 0, fmt.Errorf("failed to get schema of table %s: %w", destTable, err)
@@ -96,9 +86,11 @@ func (c *ClickhouseConnector) getTableSchema(tableName string) ([]*sql.ColumnTyp
 	return columnTypes, nil
 }
 
-func (c *ClickhouseConnector) isPartitionSynced(ctx context.Context, partitionID string) (bool, error) {
+func (c *ClickhouseConnector) IsQRepPartitionSynced(ctx context.Context,
+	req *protos.IsQRepPartitionSyncedInput,
+) (bool, error) {
 	//nolint:gosec
-	queryString := fmt.Sprintf(`SELECT COUNT(*) FROM %s WHERE partitionID = '%s'`, qRepMetadataTableName, partitionID)
+	queryString := fmt.Sprintf(`SELECT COUNT(*) FROM %s WHERE partitionID = '%s'`, qRepMetadataTableName, req.PartitionId)
 
 	row := c.database.QueryRowContext(ctx, queryString)
 

flow/connectors/core.go

@@ -146,6 +146,9 @@ type QRepPullConnector interface {
 type QRepSyncConnector interface {
 	Connector
 
+	// IsQRepPartitionSynced returns true if a partition has already been synced
+	IsQRepPartitionSynced(ctx context.Context, req *protos.IsQRepPartitionSyncedInput) (bool, error)
+
 	// SetupQRepMetadataTables sets up the metadata tables for QRep.
 	SetupQRepMetadataTables(ctx context.Context, config *protos.QRepConfig) error
 
@@ -261,6 +264,7 @@ var (
 	_ QRepSyncConnector = &connbigquery.BigQueryConnector{}
 	_ QRepSyncConnector = &connsnowflake.SnowflakeConnector{}
 	_ QRepSyncConnector = &connclickhouse.ClickhouseConnector{}
+	_ QRepSyncConnector = &conns3.S3Connector{}
 
 	_ QRepConsolidateConnector = &connsnowflake.SnowflakeConnector{}
 	_ QRepConsolidateConnector = &connclickhouse.ClickhouseConnector{}

flow/connectors/postgres/qrep.go

@@ -458,15 +458,6 @@ func (c *PostgresConnector) SyncQRepRecords(
 		return 0, fmt.Errorf("table %s does not exist, used schema: %s", dstTable.Table, dstTable.Schema)
 	}
 
-	done, err := c.isPartitionSynced(ctx, partition.PartitionId)
-	if err != nil {
-		return 0, fmt.Errorf("failed to check if partition is synced: %w", err)
-	}
-
-	if done {
-		c.logger.Info(fmt.Sprintf("partition %s already synced", partition.PartitionId))
-		return 0, nil
-	}
 	c.logger.Info("SyncRecords called and initial checks complete.")
 
 	stagingTableSync := &QRepStagingTableSync{connector: c}
@@ -573,18 +564,20 @@ func BuildQuery(logger log.Logger, query string, flowJobName string) (string, er
 	return res, nil
 }
 
-// isPartitionSynced checks whether a specific partition is synced
-func (c *PostgresConnector) isPartitionSynced(ctx context.Context, partitionID string) (bool, error) {
+// IsQRepPartitionSynced checks whether a specific partition is synced
+func (c *PostgresConnector) IsQRepPartitionSynced(ctx context.Context,
+	req *protos.IsQRepPartitionSyncedInput,
+) (bool, error) {
 	// setup the query string
 	metadataTableIdentifier := pgx.Identifier{c.metadataSchema, qRepMetadataTableName}
 	queryString := fmt.Sprintf(
-		"SELECT COUNT(*)>0 FROM %s WHERE partitionID = $1;",
+		"SELECT COUNT(*)>0 FROM %s WHERE partitionID=$1;",
 		metadataTableIdentifier.Sanitize(),
 	)
 
 	// prepare and execute the query
 	var result bool
-	err := c.conn.QueryRow(ctx, queryString, partitionID).Scan(&result)
+	err := c.conn.QueryRow(ctx, queryString, req.PartitionId).Scan(&result)
 	if err != nil {
 		return false, fmt.Errorf("failed to execute query: %w", err)
 	}

flow/connectors/s3/qrep.go

@@ -81,3 +81,10 @@ func (c *S3Connector) SetupQRepMetadataTables(_ context.Context, config *protos.
 	c.logger.Info("QRep metadata setup not needed for S3.")
 	return nil
 }
+
+// S3 doesn't check if partition is already synced, but file with same name is overwritten
+func (c *S3Connector) IsQRepPartitionSynced(_ context.Context,
+	config *protos.IsQRepPartitionSyncedInput,
+) (bool, error) {
+	return false, nil
+}

flow/connectors/snowflake/qrep.go

@@ -35,16 +35,6 @@ func (c *SnowflakeConnector) SyncQRepRecords(
 	}
 	c.logger.Info("Called QRep sync function and obtained table schema", flowLog)
 
-	done, err := c.pgMetadata.IsQrepPartitionSynced(ctx, config.FlowJobName, partition.PartitionId)
-	if err != nil {
-		return 0, fmt.Errorf("failed to check if partition %s is synced: %w", partition.PartitionId, err)
-	}
-
-	if done {
-		c.logger.Info("Partition has already been synced", flowLog)
-		return 0, nil
-	}
-
 	avroSync := NewSnowflakeAvroSyncHandler(config, c)
 	return avroSync.SyncQRepRecords(ctx, config, partition, tblSchema, stream)
 }
@@ -282,3 +272,9 @@ func (c *SnowflakeConnector) dropStage(ctx context.Context, stagingPath string,
 func (c *SnowflakeConnector) getStageNameForJob(job string) string {
 	return fmt.Sprintf("%s.peerdb_stage_%s", c.rawSchema, job)
 }
+
+func (c *SnowflakeConnector) IsQRepPartitionSynced(ctx context.Context,
+	req *protos.IsQRepPartitionSyncedInput,
+) (bool, error) {
+	return c.pgMetadata.IsQrepPartitionSynced(ctx, req.FlowJobName, req.PartitionId)
+}

protos/flow.proto

@@ -380,9 +380,14 @@ message SetupFlowOutput {
   map<string, TableSchema> table_name_schema_mapping = 2;
 }
 
-message AddTablesToPublicationInput{
+message AddTablesToPublicationInput {
   string flow_job_name = 1;
   string publication_name = 2;
   repeated TableMapping additional_tables = 3;
 }
 
+message IsQRepPartitionSyncedInput {
+  string flow_job_name = 1;
+  string partition_id = 2;
+}
+