Examples with BeginTransactionEventInfo org.apache.nifi.cdc.mysql.event.BeginTransactionEventInfo used on opensource projects

Example 1 with BeginTransactionEventInfo

use of org.apache.nifi.cdc.mysql.event.BeginTransactionEventInfo in project nifi by apache.

the class CaptureChangeMySQL method outputEvents.

public void outputEvents(ProcessSession session, StateManager stateManager, ComponentLog log) throws IOException {
    RawBinlogEvent rawBinlogEvent;
    // Drain the queue
    while ((rawBinlogEvent = queue.poll()) != null && !doStop.get()) {
        Event event = rawBinlogEvent.getEvent();
        EventHeaderV4 header = event.getHeader();
        long timestamp = header.getTimestamp();
        EventType eventType = header.getEventType();
        // is filled in during the ROTATE case
        if (eventType != ROTATE && eventType != FORMAT_DESCRIPTION) {
            currentBinlogPosition = header.getPosition();
        }
        log.debug("Got message event type: {} ", new Object[] { header.getEventType().toString() });
        switch(eventType) {
            case TABLE_MAP:
                // This is sent to inform which table is about to be changed by subsequent events
                TableMapEventData data = event.getData();
                // Should we skip this table? Yes if we've specified a DB or table name pattern and they don't match
                skipTable = (databaseNamePattern != null && !databaseNamePattern.matcher(data.getDatabase()).matches()) || (tableNamePattern != null && !tableNamePattern.matcher(data.getTable()).matches());
                if (!skipTable) {
                    TableInfoCacheKey key = new TableInfoCacheKey(this.getIdentifier(), data.getDatabase(), data.getTable(), data.getTableId());
                    if (cacheClient != null) {
                        try {
                            currentTable = cacheClient.get(key, cacheKeySerializer, cacheValueDeserializer);
                        } catch (ConnectException ce) {
                            throw new IOException("Could not connect to Distributed Map Cache server to get table information", ce);
                        }
                        if (currentTable == null) {
                            // We don't have an entry for this table yet, so fetch the info from the database and populate the cache
                            try {
                                currentTable = loadTableInfo(key);
                                try {
                                    cacheClient.put(key, currentTable, cacheKeySerializer, cacheValueSerializer);
                                } catch (ConnectException ce) {
                                    throw new IOException("Could not connect to Distributed Map Cache server to put table information", ce);
                                }
                            } catch (SQLException se) {
                                // Propagate the error up, so things like rollback and logging/bulletins can be handled
                                throw new IOException(se.getMessage(), se);
                            }
                        }
                    }
                } else {
                    // Clear the current table, to force a reload next time we get a TABLE_MAP event we care about
                    currentTable = null;
                }
                break;
            case QUERY:
                QueryEventData queryEventData = event.getData();
                currentDatabase = queryEventData.getDatabase();
                String sql = queryEventData.getSql();
                // Is this the start of a transaction?
                if ("BEGIN".equals(sql)) {
                    // If we're already in a transaction, something bad happened, alert the user
                    if (inTransaction) {
                        throw new IOException("BEGIN event received while already processing a transaction. This could indicate that your binlog position is invalid.");
                    }
                    // Mark the current binlog position in case we have to rollback the transaction (if the processor is stopped, e.g.)
                    xactBinlogFile = currentBinlogFile;
                    xactBinlogPosition = currentBinlogPosition;
                    xactSequenceId = currentSequenceId.get();
                    if (includeBeginCommit && (databaseNamePattern == null || databaseNamePattern.matcher(currentDatabase).matches())) {
                        BeginTransactionEventInfo beginEvent = new BeginTransactionEventInfo(currentDatabase, timestamp, currentBinlogFile, currentBinlogPosition);
                        currentSequenceId.set(beginEventWriter.writeEvent(currentSession, transitUri, beginEvent, currentSequenceId.get(), REL_SUCCESS));
                    }
                    inTransaction = true;
                } else if ("COMMIT".equals(sql)) {
                    if (!inTransaction) {
                        throw new IOException("COMMIT event received while not processing a transaction (i.e. no corresponding BEGIN event). " + "This could indicate that your binlog position is invalid.");
                    }
                    // InnoDB generates XID events for "commit", but MyISAM generates Query events with "COMMIT", so handle that here
                    if (includeBeginCommit && (databaseNamePattern == null || databaseNamePattern.matcher(currentDatabase).matches())) {
                        CommitTransactionEventInfo commitTransactionEvent = new CommitTransactionEventInfo(currentDatabase, timestamp, currentBinlogFile, currentBinlogPosition);
                        currentSequenceId.set(commitEventWriter.writeEvent(currentSession, transitUri, commitTransactionEvent, currentSequenceId.get(), REL_SUCCESS));
                    }
                    // Commit the NiFi session
                    session.commit();
                    inTransaction = false;
                    currentTable = null;
                } else {
                    // Check for DDL events (alter table, e.g.). Normalize the query to do string matching on the type of change
                    String normalizedQuery = sql.toLowerCase().trim().replaceAll(" {2,}", " ");
                    if (normalizedQuery.startsWith("alter table") || normalizedQuery.startsWith("alter ignore table") || normalizedQuery.startsWith("create table") || normalizedQuery.startsWith("truncate table") || normalizedQuery.startsWith("rename table") || normalizedQuery.startsWith("drop table") || normalizedQuery.startsWith("drop database")) {
                        if (includeDDLEvents && (databaseNamePattern == null || databaseNamePattern.matcher(currentDatabase).matches())) {
                            // If we don't have table information, we can still use the database name
                            TableInfo ddlTableInfo = (currentTable != null) ? currentTable : new TableInfo(currentDatabase, null, null, null);
                            DDLEventInfo ddlEvent = new DDLEventInfo(ddlTableInfo, timestamp, currentBinlogFile, currentBinlogPosition, sql);
                            currentSequenceId.set(ddlEventWriter.writeEvent(currentSession, transitUri, ddlEvent, currentSequenceId.get(), REL_SUCCESS));
                        }
                        // Remove all the keys from the cache that this processor added
                        if (cacheClient != null) {
                            cacheClient.removeByPattern(this.getIdentifier() + ".*");
                        }
                        // If not in a transaction, commit the session so the DDL event(s) will be transferred
                        if (includeDDLEvents && !inTransaction) {
                            session.commit();
                        }
                    }
                }
                break;
            case XID:
                if (!inTransaction) {
                    throw new IOException("COMMIT event received while not processing a transaction (i.e. no corresponding BEGIN event). " + "This could indicate that your binlog position is invalid.");
                }
                if (includeBeginCommit && (databaseNamePattern == null || databaseNamePattern.matcher(currentDatabase).matches())) {
                    CommitTransactionEventInfo commitTransactionEvent = new CommitTransactionEventInfo(currentDatabase, timestamp, currentBinlogFile, currentBinlogPosition);
                    currentSequenceId.set(commitEventWriter.writeEvent(currentSession, transitUri, commitTransactionEvent, currentSequenceId.get(), REL_SUCCESS));
                }
                // Commit the NiFi session
                session.commit();
                inTransaction = false;
                currentTable = null;
                currentDatabase = null;
                break;
            case WRITE_ROWS:
            case EXT_WRITE_ROWS:
            case PRE_GA_WRITE_ROWS:
            case UPDATE_ROWS:
            case EXT_UPDATE_ROWS:
            case PRE_GA_UPDATE_ROWS:
            case DELETE_ROWS:
            case EXT_DELETE_ROWS:
            case PRE_GA_DELETE_ROWS:
                // If we are skipping this table, then don't emit any events related to its modification
                if (skipTable) {
                    break;
                }
                if (!inTransaction) {
                    // These events should only happen inside a transaction, warn the user otherwise
                    log.warn("Table modification event occurred outside of a transaction.");
                    break;
                }
                if (currentTable == null && cacheClient != null) {
                    // No Table Map event was processed prior to this event, which should not happen, so throw an error
                    throw new RowEventException("No table information is available for this event, cannot process further.");
                }
                if (eventType == WRITE_ROWS || eventType == EXT_WRITE_ROWS || eventType == PRE_GA_WRITE_ROWS) {
                    InsertRowsEventInfo eventInfo = new InsertRowsEventInfo(currentTable, timestamp, currentBinlogFile, currentBinlogPosition, event.getData());
                    currentSequenceId.set(insertRowsWriter.writeEvent(currentSession, transitUri, eventInfo, currentSequenceId.get(), REL_SUCCESS));
                } else if (eventType == DELETE_ROWS || eventType == EXT_DELETE_ROWS || eventType == PRE_GA_DELETE_ROWS) {
                    DeleteRowsEventInfo eventInfo = new DeleteRowsEventInfo(currentTable, timestamp, currentBinlogFile, currentBinlogPosition, event.getData());
                    currentSequenceId.set(deleteRowsWriter.writeEvent(currentSession, transitUri, eventInfo, currentSequenceId.get(), REL_SUCCESS));
                } else {
                    // Update event
                    UpdateRowsEventInfo eventInfo = new UpdateRowsEventInfo(currentTable, timestamp, currentBinlogFile, currentBinlogPosition, event.getData());
                    currentSequenceId.set(updateRowsWriter.writeEvent(currentSession, transitUri, eventInfo, currentSequenceId.get(), REL_SUCCESS));
                }
                break;
            case ROTATE:
                // Update current binlog filename
                RotateEventData rotateEventData = event.getData();
                currentBinlogFile = rotateEventData.getBinlogFilename();
                currentBinlogPosition = rotateEventData.getBinlogPosition();
                break;
            default:
                break;
        }
        // advance the position if it is not that type of event.
        if (eventType != ROTATE && eventType != FORMAT_DESCRIPTION) {
            currentBinlogPosition = header.getNextPosition();
        }
    }
}