Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.apache.nifi.cdc.mysql.processors; import com.github.shyiko.mysql.binlog.BinaryLogClient; import com.github.shyiko.mysql.binlog.event.Event; import com.github.shyiko.mysql.binlog.event.EventHeaderV4; import com.github.shyiko.mysql.binlog.event.EventType; import com.github.shyiko.mysql.binlog.event.QueryEventData; import com.github.shyiko.mysql.binlog.event.RotateEventData; import com.github.shyiko.mysql.binlog.event.TableMapEventData; import org.apache.commons.lang3.StringUtils; import org.apache.nifi.annotation.behavior.InputRequirement; import org.apache.nifi.annotation.behavior.Stateful; import org.apache.nifi.annotation.behavior.TriggerSerially; import org.apache.nifi.annotation.behavior.WritesAttribute; import org.apache.nifi.annotation.behavior.WritesAttributes; import org.apache.nifi.annotation.documentation.CapabilityDescription; import org.apache.nifi.annotation.documentation.Tags; import org.apache.nifi.annotation.lifecycle.OnShutdown; import org.apache.nifi.annotation.lifecycle.OnStopped; import org.apache.nifi.cdc.CDCException; import org.apache.nifi.cdc.event.ColumnDefinition; import org.apache.nifi.cdc.event.RowEventException; import org.apache.nifi.cdc.event.TableInfo; import org.apache.nifi.cdc.event.TableInfoCacheKey; import org.apache.nifi.cdc.event.io.EventWriter; import org.apache.nifi.cdc.mysql.event.BeginTransactionEventInfo; import org.apache.nifi.cdc.mysql.event.BinlogEventInfo; import org.apache.nifi.cdc.mysql.event.BinlogEventListener; import org.apache.nifi.cdc.mysql.event.BinlogLifecycleListener; import org.apache.nifi.cdc.mysql.event.CommitTransactionEventInfo; import org.apache.nifi.cdc.mysql.event.DeleteRowsEventInfo; import org.apache.nifi.cdc.mysql.event.InsertRowsEventInfo; import org.apache.nifi.cdc.mysql.event.RawBinlogEvent; import org.apache.nifi.cdc.mysql.event.DDLEventInfo; import org.apache.nifi.cdc.mysql.event.UpdateRowsEventInfo; import org.apache.nifi.cdc.mysql.event.io.BeginTransactionEventWriter; import org.apache.nifi.cdc.mysql.event.io.CommitTransactionEventWriter; import org.apache.nifi.cdc.mysql.event.io.DeleteRowsWriter; import org.apache.nifi.cdc.mysql.event.io.InsertRowsWriter; import org.apache.nifi.cdc.mysql.event.io.DDLEventWriter; import org.apache.nifi.cdc.mysql.event.io.UpdateRowsWriter; import org.apache.nifi.components.PropertyDescriptor; import org.apache.nifi.components.PropertyValue; import org.apache.nifi.components.state.Scope; import org.apache.nifi.components.state.StateManager; import org.apache.nifi.components.state.StateMap; import org.apache.nifi.distributed.cache.client.Deserializer; import org.apache.nifi.distributed.cache.client.DistributedMapCacheClient; import org.apache.nifi.distributed.cache.client.Serializer; import org.apache.nifi.logging.ComponentLog; import org.apache.nifi.processor.AbstractSessionFactoryProcessor; import org.apache.nifi.processor.ProcessContext; import org.apache.nifi.processor.ProcessSession; import org.apache.nifi.processor.ProcessSessionFactory; import org.apache.nifi.processor.Relationship; import org.apache.nifi.processor.exception.ProcessException; import org.apache.nifi.processor.util.StandardValidators; import org.apache.nifi.reporting.InitializationException; import org.apache.nifi.util.file.classloader.ClassLoaderUtils; import java.io.IOException; import java.net.ConnectException; import java.net.InetSocketAddress; import java.net.MalformedURLException; import java.sql.Connection; import java.sql.Driver; import java.sql.DriverManager; import java.sql.DriverPropertyInfo; import java.sql.ResultSet; import java.sql.ResultSetMetaData; import java.sql.SQLException; import java.sql.SQLFeatureNotSupportedException; import java.sql.Statement; import java.util.ArrayList; import java.util.Arrays; import java.util.Collections; import java.util.HashMap; import java.util.HashSet; import java.util.List; import java.util.Map; import java.util.Properties; import java.util.Set; import java.util.concurrent.LinkedBlockingQueue; import java.util.concurrent.TimeUnit; import java.util.concurrent.TimeoutException; import java.util.concurrent.atomic.AtomicBoolean; import java.util.concurrent.atomic.AtomicLong; import java.util.logging.Logger; import java.util.regex.Pattern; import static com.github.shyiko.mysql.binlog.event.EventType.DELETE_ROWS; import static com.github.shyiko.mysql.binlog.event.EventType.EXT_DELETE_ROWS; import static com.github.shyiko.mysql.binlog.event.EventType.EXT_WRITE_ROWS; import static com.github.shyiko.mysql.binlog.event.EventType.FORMAT_DESCRIPTION; import static com.github.shyiko.mysql.binlog.event.EventType.PRE_GA_DELETE_ROWS; import static com.github.shyiko.mysql.binlog.event.EventType.PRE_GA_WRITE_ROWS; import static com.github.shyiko.mysql.binlog.event.EventType.ROTATE; import static com.github.shyiko.mysql.binlog.event.EventType.WRITE_ROWS; /** * A processor to retrieve Change Data Capture (CDC) events and send them as flow files. */ @TriggerSerially @InputRequirement(InputRequirement.Requirement.INPUT_FORBIDDEN) @Tags({ "sql", "jdbc", "cdc", "mysql" }) @CapabilityDescription("Retrieves Change Data Capture (CDC) events from a MySQL database. CDC Events include INSERT, UPDATE, DELETE operations. Events " + "are output as individual flow files ordered by the time at which the operation occurred.") @Stateful(scopes = Scope.CLUSTER, description = "Information such as a 'pointer' to the current CDC event in the database is stored by this processor, such " + "that it can continue from the same location if restarted.") @WritesAttributes({ @WritesAttribute(attribute = EventWriter.SEQUENCE_ID_KEY, description = "A sequence identifier (i.e. strictly increasing integer value) specifying the order " + "of the CDC event flow file relative to the other event flow file(s)."), @WritesAttribute(attribute = EventWriter.CDC_EVENT_TYPE_ATTRIBUTE, description = "A string indicating the type of CDC event that occurred, including (but not limited to) " + "'begin', 'insert', 'update', 'delete', 'ddl' and 'commit'."), @WritesAttribute(attribute = "mime.type", description = "The processor outputs flow file content in JSON format, and sets the mime.type attribute to " + "application/json") }) public class CaptureChangeMySQL extends AbstractSessionFactoryProcessor { // Random invalid constant used as an indicator to not set the binlog position on the client (thereby using the latest available) private static final int DO_NOT_SET = -1000; // Relationships public static final Relationship REL_SUCCESS = new Relationship.Builder().name("success") .description("Successfully created FlowFile from SQL query result set.").build(); protected static Set<Relationship> relationships; // Properties public static final PropertyDescriptor DATABASE_NAME_PATTERN = new PropertyDescriptor.Builder() .name("capture-change-mysql-db-name-pattern").displayName("Database/Schema Name Pattern") .description( "A regular expression (regex) for matching databases (or schemas, depending on your RDBMS' terminology) against the list of CDC events. The regex must match " + "the database name as it is stored in the RDBMS. If the property is not set, the database name will not be used to filter the CDC events. " + "NOTE: DDL events, even if they affect different databases, are associated with the database used by the session to execute the DDL. " + "This means if a connection is made to one database, but the DDL is issued against another, then the connected database will be the one matched against " + "the specified pattern.") .required(false).addValidator(StandardValidators.NON_EMPTY_VALIDATOR).build(); public static final PropertyDescriptor TABLE_NAME_PATTERN = new PropertyDescriptor.Builder() .name("capture-change-mysql-name-pattern").displayName("Table Name Pattern") .description( "A regular expression (regex) for matching CDC events affecting matching tables. The regex must match the table name as it is stored in the database. " + "If the property is not set, no events will be filtered based on table name.") .required(false).addValidator(StandardValidators.NON_EMPTY_VALIDATOR).build(); public static final PropertyDescriptor CONNECT_TIMEOUT = new PropertyDescriptor.Builder() .name("capture-change-mysql-max-wait-time").displayName("Max Wait Time") .description( "The maximum amount of time allowed for a connection to be established, zero means there is effectively no limit.") .defaultValue("30 seconds").required(true).addValidator(StandardValidators.TIME_PERIOD_VALIDATOR) .expressionLanguageSupported(true).build(); public static final PropertyDescriptor HOSTS = new PropertyDescriptor.Builder() .name("capture-change-mysql-hosts").displayName("MySQL Hosts") .description( "A list of hostname/port entries corresponding to nodes in a MySQL cluster. The entries should be comma separated " + "using a colon such as host1:port,host2:port,.... For example mysql.myhost.com:3306. This processor will attempt to connect to " + "the hosts in the list in order. If one node goes down and failover is enabled for the cluster, then the processor will connect " + "to the active node (assuming its host entry is specified in this property. The default port for MySQL connections is 3306.") .required(true).expressionLanguageSupported(false) .addValidator(StandardValidators.HOSTNAME_PORT_LIST_VALIDATOR).expressionLanguageSupported(true) .build(); public static final PropertyDescriptor DRIVER_NAME = new PropertyDescriptor.Builder() .name("capture-change-mysql-driver-class").displayName("MySQL Driver Class Name") .description("The class name of the MySQL database driver class").defaultValue("com.mysql.jdbc.Driver") .required(true).addValidator(StandardValidators.NON_EMPTY_VALIDATOR).expressionLanguageSupported(true) .build(); public static final PropertyDescriptor DRIVER_LOCATION = new PropertyDescriptor.Builder() .name("capture-change-mysql-driver-locations").displayName("MySQL Driver Location(s)") .description( "Comma-separated list of files/folders and/or URLs containing the MySQL driver JAR and its dependencies (if any). " + "For example '/var/tmp/mysql-connector-java-5.1.38-bin.jar'") .defaultValue(null).required(false).addValidator(StandardValidators.createListValidator(true, true, StandardValidators.createURLorFileValidator())) .expressionLanguageSupported(true).build(); public static final PropertyDescriptor USERNAME = new PropertyDescriptor.Builder() .name("capture-change-mysql-username").displayName("Username") .description("Username to access the MySQL cluster").required(false) .addValidator(StandardValidators.NON_EMPTY_VALIDATOR).expressionLanguageSupported(true).build(); public static final PropertyDescriptor PASSWORD = new PropertyDescriptor.Builder() .name("capture-change-mysql-password").displayName("Password") .description("Password to access the MySQL cluster").required(false).sensitive(true) .addValidator(StandardValidators.NON_EMPTY_VALIDATOR).expressionLanguageSupported(true).build(); public static final PropertyDescriptor SERVER_ID = new PropertyDescriptor.Builder() .name("capture-change-mysql-server-id").displayName("Server ID") .description( "The client connecting to the MySQL replication group is actually a simplified slave (server), and the Server ID value must be unique across the whole replication " + "group (i.e. different from any other Server ID being used by any master or slave). Thus, each instance of CaptureChangeMySQL must have a Server ID unique across " + "the replication group. If the Server ID is not specified, it defaults to 65535.") .required(false).addValidator(StandardValidators.POSITIVE_LONG_VALIDATOR) .expressionLanguageSupported(true).build(); public static final PropertyDescriptor DIST_CACHE_CLIENT = new PropertyDescriptor.Builder() .name("capture-change-mysql-dist-map-cache-client").displayName("Distributed Map Cache Client") .description( "Identifies a Distributed Map Cache Client controller service to be used for keeping information about the various tables, columns, etc. " + "needed by the processor. If a client is not specified, the generated events will not include column type or name information.") .identifiesControllerService(DistributedMapCacheClient.class).required(false).build(); public static final PropertyDescriptor RETRIEVE_ALL_RECORDS = new PropertyDescriptor.Builder() .name("capture-change-mysql-retrieve-all-records").displayName("Retrieve All Records") .description( "Specifies whether to get all available CDC events, regardless of the current binlog filename and/or position. If binlog filename and position values are present " + "in the processor's State, this property's value is ignored. This allows for 4 different configurations: 1) If binlog data is available in processor State, that is used " + "to determine the start location and the value of Retrieve All Records is ignored. 2) If no binlog data is in processor State, then Retrieve All Records set to true " + "means start at the beginning of the binlog history. 3) If no binlog data is in processor State and Initial Binlog Filename/Position are not set, then " + "Retrieve All Records set to false means start at the end of the binlog history. 4) If no binlog data is in processor State and Initial Binlog Filename/Position " + "are set, then Retrieve All Records set to false means start at the specified initial binlog file/position. " + "To reset the behavior, clear the processor state (refer to the State Management section of the processor's documentation).") .required(true).allowableValues("true", "false").defaultValue("true") .addValidator(StandardValidators.BOOLEAN_VALIDATOR).build(); public static final PropertyDescriptor INCLUDE_BEGIN_COMMIT = new PropertyDescriptor.Builder() .name("capture-change-mysql-include-begin-commit").displayName("Include Begin/Commit Events") .description( "Specifies whether to emit events corresponding to a BEGIN or COMMIT event in the binary log. Set to true if the BEGIN/COMMIT events are necessary in the downstream flow, " + "otherwise set to false, which suppresses generation of these events and can increase flow performance.") .required(true).allowableValues("true", "false").defaultValue("false") .addValidator(StandardValidators.BOOLEAN_VALIDATOR).build(); public static final PropertyDescriptor INCLUDE_DDL_EVENTS = new PropertyDescriptor.Builder() .name("capture-change-mysql-include-ddl-events").displayName("Include DDL Events") .description( "Specifies whether to emit events corresponding to Data Definition Language (DDL) events such as ALTER TABLE, TRUNCATE TABLE, e.g. in the binary log. Set to true " + "if the DDL events are desired/necessary in the downstream flow, otherwise set to false, which suppresses generation of these events and can increase flow performance.") .required(true).allowableValues("true", "false").defaultValue("false") .addValidator(StandardValidators.BOOLEAN_VALIDATOR).build(); public static final PropertyDescriptor STATE_UPDATE_INTERVAL = new PropertyDescriptor.Builder() .name("capture-change-mysql-state-update-interval").displayName("State Update Interval") .description( "Indicates how often to update the processor's state with binlog file/position values. A value of zero means that state will only be updated when the processor is " + "stopped or shutdown. If at some point the processor state does not contain the desired binlog values, the last flow file emitted will contain the last observed values, " + "and the processor can be returned to that state by using the Initial Binlog File, Initial Binlog Position, and Initial Sequence ID properties.") .defaultValue("0 seconds").required(true).addValidator(StandardValidators.TIME_PERIOD_VALIDATOR) .expressionLanguageSupported(true).build(); public static final PropertyDescriptor INIT_SEQUENCE_ID = new PropertyDescriptor.Builder() .name("capture-change-mysql-init-seq-id").displayName("Initial Sequence ID") .description( "Specifies an initial sequence identifier to use if this processor's State does not have a current " + "sequence identifier. If a sequence identifier is present in the processor's State, this property is ignored. Sequence identifiers are " + "monotonically increasing integers that record the order of flow files generated by the processor. They can be used with the EnforceOrder " + "processor to guarantee ordered delivery of CDC events.") .required(false).addValidator(StandardValidators.NON_NEGATIVE_INTEGER_VALIDATOR) .expressionLanguageSupported(true).build(); public static final PropertyDescriptor INIT_BINLOG_FILENAME = new PropertyDescriptor.Builder() .name("capture-change-mysql-init-binlog-filename").displayName("Initial Binlog Filename") .description( "Specifies an initial binlog filename to use if this processor's State does not have a current binlog filename. If a filename is present " + "in the processor's State, this property is ignored. This can be used along with Initial Binlog Position to \"skip ahead\" if previous events are not desired. " + "Note that NiFi Expression Language is supported, but this property is evaluated when the processor is configured, so FlowFile attributes may not be used. Expression " + "Language is supported to enable the use of the Variable Registry and/or environment properties.") .required(false).addValidator(StandardValidators.NON_EMPTY_VALIDATOR).expressionLanguageSupported(true) .build(); public static final PropertyDescriptor INIT_BINLOG_POSITION = new PropertyDescriptor.Builder() .name("capture-change-mysql-init-binlog-position").displayName("Initial Binlog Position") .description( "Specifies an initial offset into a binlog (specified by Initial Binlog Filename) to use if this processor's State does not have a current " + "binlog filename. If a filename is present in the processor's State, this property is ignored. This can be used along with Initial Binlog Filename " + "to \"skip ahead\" if previous events are not desired. Note that NiFi Expression Language is supported, but this property is evaluated when the " + "processor is configured, so FlowFile attributes may not be used. Expression Language is supported to enable the use of the Variable Registry " + "and/or environment properties.") .required(false).addValidator(StandardValidators.NON_NEGATIVE_INTEGER_VALIDATOR) .expressionLanguageSupported(true).build(); private static List<PropertyDescriptor> propDescriptors; private volatile ProcessSession currentSession; private BinaryLogClient binlogClient; private BinlogEventListener eventListener; private BinlogLifecycleListener lifecycleListener; private volatile LinkedBlockingQueue<RawBinlogEvent> queue = new LinkedBlockingQueue<>(); private volatile String currentBinlogFile = null; private volatile long currentBinlogPosition = 4; // The following variables save the value of the binlog filename and position (and sequence id) at the beginning of a transaction. Used for rollback private volatile String xactBinlogFile = null; private volatile long xactBinlogPosition = 4; private volatile long xactSequenceId = 0; private volatile TableInfo currentTable = null; private volatile String currentDatabase = null; private volatile Pattern databaseNamePattern; private volatile Pattern tableNamePattern; private volatile boolean includeBeginCommit = false; private volatile boolean includeDDLEvents = false; private volatile boolean inTransaction = false; private volatile boolean skipTable = false; private AtomicBoolean doStop = new AtomicBoolean(false); private AtomicBoolean hasRun = new AtomicBoolean(false); private int currentHost = 0; private String transitUri = "<unknown>"; private volatile long lastStateUpdate = 0L; private volatile long stateUpdateInterval = -1L; private AtomicLong currentSequenceId = new AtomicLong(0); private volatile DistributedMapCacheClient cacheClient = null; private final Serializer<TableInfoCacheKey> cacheKeySerializer = new TableInfoCacheKey.Serializer(); private final Serializer<TableInfo> cacheValueSerializer = new TableInfo.Serializer(); private final Deserializer<TableInfo> cacheValueDeserializer = new TableInfo.Deserializer(); private Connection jdbcConnection = null; private final BeginTransactionEventWriter beginEventWriter = new BeginTransactionEventWriter(); private final CommitTransactionEventWriter commitEventWriter = new CommitTransactionEventWriter(); private final DDLEventWriter ddlEventWriter = new DDLEventWriter(); private final InsertRowsWriter insertRowsWriter = new InsertRowsWriter(); private final DeleteRowsWriter deleteRowsWriter = new DeleteRowsWriter(); private final UpdateRowsWriter updateRowsWriter = new UpdateRowsWriter(); static { final Set<Relationship> r = new HashSet<>(); r.add(REL_SUCCESS); relationships = Collections.unmodifiableSet(r); final List<PropertyDescriptor> pds = new ArrayList<>(); pds.add(HOSTS); pds.add(DRIVER_NAME); pds.add(DRIVER_LOCATION); pds.add(USERNAME); pds.add(PASSWORD); pds.add(SERVER_ID); pds.add(DATABASE_NAME_PATTERN); pds.add(TABLE_NAME_PATTERN); pds.add(CONNECT_TIMEOUT); pds.add(DIST_CACHE_CLIENT); pds.add(RETRIEVE_ALL_RECORDS); pds.add(INCLUDE_BEGIN_COMMIT); pds.add(INCLUDE_DDL_EVENTS); pds.add(STATE_UPDATE_INTERVAL); pds.add(INIT_SEQUENCE_ID); pds.add(INIT_BINLOG_FILENAME); pds.add(INIT_BINLOG_POSITION); propDescriptors = Collections.unmodifiableList(pds); } @Override public Set<Relationship> getRelationships() { return relationships; } @Override protected List<PropertyDescriptor> getSupportedPropertyDescriptors() { return propDescriptors; } public void setup(ProcessContext context) { final ComponentLog logger = getLogger(); final StateManager stateManager = context.getStateManager(); final StateMap stateMap; try { stateMap = stateManager.getState(Scope.CLUSTER); } catch (final IOException ioe) { logger.error("Failed to retrieve observed maximum values from the State Manager. Will not attempt " + "connection until this is accomplished.", ioe); context.yield(); return; } PropertyValue dbNameValue = context.getProperty(DATABASE_NAME_PATTERN); databaseNamePattern = dbNameValue.isSet() ? Pattern.compile(dbNameValue.getValue()) : null; PropertyValue tableNameValue = context.getProperty(TABLE_NAME_PATTERN); tableNamePattern = tableNameValue.isSet() ? Pattern.compile(tableNameValue.getValue()) : null; stateUpdateInterval = context.getProperty(STATE_UPDATE_INTERVAL).evaluateAttributeExpressions() .asTimePeriod(TimeUnit.MILLISECONDS); boolean getAllRecords = context.getProperty(RETRIEVE_ALL_RECORDS).asBoolean(); includeBeginCommit = context.getProperty(INCLUDE_BEGIN_COMMIT).asBoolean(); includeDDLEvents = context.getProperty(INCLUDE_DDL_EVENTS).asBoolean(); // Set current binlog filename to whatever is in State, falling back to the Retrieve All Records then Initial Binlog Filename if no State variable is present currentBinlogFile = stateMap.get(BinlogEventInfo.BINLOG_FILENAME_KEY); if (currentBinlogFile == null) { if (!getAllRecords) { if (context.getProperty(INIT_BINLOG_FILENAME).isSet()) { currentBinlogFile = context.getProperty(INIT_BINLOG_FILENAME).evaluateAttributeExpressions() .getValue(); } } else { // If we're starting from the beginning of all binlogs, the binlog filename must be the empty string (not null) currentBinlogFile = ""; } } // Set current binlog position to whatever is in State, falling back to the Retrieve All Records then Initial Binlog Filename if no State variable is present String binlogPosition = stateMap.get(BinlogEventInfo.BINLOG_POSITION_KEY); if (binlogPosition != null) { currentBinlogPosition = Long.valueOf(binlogPosition); } else if (!getAllRecords) { if (context.getProperty(INIT_BINLOG_POSITION).isSet()) { currentBinlogPosition = context.getProperty(INIT_BINLOG_POSITION).evaluateAttributeExpressions() .asLong(); } else { currentBinlogPosition = DO_NOT_SET; } } else { currentBinlogPosition = -1; } // Get current sequence ID from state String seqIdString = stateMap.get(EventWriter.SEQUENCE_ID_KEY); if (StringUtils.isEmpty(seqIdString)) { // Use Initial Sequence ID property if none is found in state PropertyValue seqIdProp = context.getProperty(INIT_SEQUENCE_ID); if (seqIdProp.isSet()) { currentSequenceId.set(seqIdProp.evaluateAttributeExpressions().asInteger()); } } else { currentSequenceId.set(Integer.parseInt(seqIdString)); } // Get reference to Distributed Cache if one exists. If it does not, no enrichment (resolution of column names, e.g.) will be performed boolean createEnrichmentConnection = false; if (context.getProperty(DIST_CACHE_CLIENT).isSet()) { cacheClient = context.getProperty(DIST_CACHE_CLIENT) .asControllerService(DistributedMapCacheClient.class); createEnrichmentConnection = true; } else { logger.warn( "No Distributed Map Cache Client is specified, so no event enrichment (resolution of column names, e.g.) will be performed."); cacheClient = null; } // Save off MySQL cluster and JDBC driver information, will be used to connect for event enrichment as well as for the binlog connector try { List<InetSocketAddress> hosts = getHosts( context.getProperty(HOSTS).evaluateAttributeExpressions().getValue()); String username = context.getProperty(USERNAME).evaluateAttributeExpressions().getValue(); String password = context.getProperty(PASSWORD).evaluateAttributeExpressions().getValue(); // BinaryLogClient expects a non-null password, so set it to the empty string if it is not provided if (password == null) { password = ""; } long connectTimeout = context.getProperty(CONNECT_TIMEOUT).evaluateAttributeExpressions() .asTimePeriod(TimeUnit.MILLISECONDS); String driverLocation = context.getProperty(DRIVER_LOCATION).evaluateAttributeExpressions().getValue(); String driverName = context.getProperty(DRIVER_NAME).evaluateAttributeExpressions().getValue(); Long serverId = context.getProperty(SERVER_ID).evaluateAttributeExpressions().asLong(); connect(hosts, username, password, serverId, createEnrichmentConnection, driverLocation, driverName, connectTimeout); } catch (IOException | IllegalStateException e) { context.yield(); binlogClient = null; throw new ProcessException(e.getMessage(), e); } } @Override public void onTrigger(ProcessContext context, ProcessSessionFactory sessionFactory) throws ProcessException { // Indicate that this processor has executed at least once, so we know whether or not the state values are valid and should be updated hasRun.set(true); ComponentLog log = getLogger(); StateManager stateManager = context.getStateManager(); // Create a client if we don't have one if (binlogClient == null) { setup(context); } // If the client has been disconnected, try to reconnect if (!binlogClient.isConnected()) { Exception e = lifecycleListener.getException(); // If there's no exception, the listener callback might not have been executed yet, so try again later. Otherwise clean up and start over next time if (e != null) { // Communications failure, disconnect and try next time log.error("Binlog connector communications failure: " + e.getMessage(), e); try { stop(stateManager); } catch (CDCException ioe) { throw new ProcessException(ioe); } } // Try again later context.yield(); return; } if (currentSession == null) { currentSession = sessionFactory.createSession(); } try { outputEvents(currentSession, stateManager, log); long now = System.currentTimeMillis(); long timeSinceLastUpdate = now - lastStateUpdate; if (stateUpdateInterval != 0 && timeSinceLastUpdate >= stateUpdateInterval) { updateState(stateManager, currentBinlogFile, currentBinlogPosition, currentSequenceId.get()); lastStateUpdate = now; } } catch (IOException ioe) { try { // Perform some processor-level "rollback", then rollback the session currentBinlogFile = xactBinlogFile == null ? "" : xactBinlogFile; currentBinlogPosition = xactBinlogPosition; currentSequenceId.set(xactSequenceId); inTransaction = false; stop(stateManager); queue.clear(); currentSession.rollback(); } catch (Exception e) { // Not much we can recover from here log.warn("Error occurred during rollback", e); } throw new ProcessException(ioe); } } @OnStopped public void onStopped(ProcessContext context) { try { stop(context.getStateManager()); } catch (CDCException ioe) { throw new ProcessException(ioe); } } @OnShutdown public void onShutdown(ProcessContext context) { try { // In case we get shutdown while still running, save off the current state, disconnect, and shut down gracefully stop(context.getStateManager()); } catch (CDCException ioe) { throw new ProcessException(ioe); } } /** * Get a list of hosts from a NiFi property, e.g. * * @param hostsString A comma-separated list of hosts (host:port,host2:port2, etc.) * @return List of InetSocketAddresses for the hosts */ private List<InetSocketAddress> getHosts(String hostsString) { if (hostsString == null) { return null; } final List<String> hostsSplit = Arrays.asList(hostsString.split(",")); List<InetSocketAddress> hostsList = new ArrayList<>(); for (String item : hostsSplit) { String[] addresses = item.split(":"); if (addresses.length != 2) { throw new ArrayIndexOutOfBoundsException("Not in host:port format"); } hostsList.add(new InetSocketAddress(addresses[0].trim(), Integer.parseInt(addresses[1].trim()))); } return hostsList; } protected void connect(List<InetSocketAddress> hosts, String username, String password, Long serverId, boolean createEnrichmentConnection, String driverLocation, String driverName, long connectTimeout) throws IOException { int connectionAttempts = 0; final int numHosts = hosts.size(); InetSocketAddress connectedHost = null; Exception lastConnectException = new Exception("Unknown connection error"); if (createEnrichmentConnection) { try { // Ensure driverLocation and driverName are correct before establishing binlog connection // to avoid failing after binlog messages are received. // Actual JDBC connection is created after binlog client gets started, because we need // the connect-able host same as the binlog client. registerDriver(driverLocation, driverName); } catch (InitializationException e) { throw new RuntimeException("Failed to register JDBC driver. Ensure MySQL Driver Location(s)" + " and MySQL Driver Class Name are configured correctly. " + e, e); } } while (connectedHost == null && connectionAttempts < numHosts) { if (binlogClient == null) { connectedHost = hosts.get(currentHost); binlogClient = createBinlogClient(connectedHost.getHostString(), connectedHost.getPort(), username, password); } // Add an event listener and lifecycle listener for binlog and client events, respectively if (eventListener == null) { eventListener = createBinlogEventListener(binlogClient, queue); } eventListener.start(); binlogClient.registerEventListener(eventListener); if (lifecycleListener == null) { lifecycleListener = createBinlogLifecycleListener(); } binlogClient.registerLifecycleListener(lifecycleListener); binlogClient.setBinlogFilename(currentBinlogFile); if (currentBinlogPosition != DO_NOT_SET) { binlogClient.setBinlogPosition(currentBinlogPosition); } if (serverId != null) { binlogClient.setServerId(serverId); } try { if (connectTimeout == 0) { connectTimeout = Long.MAX_VALUE; } binlogClient.connect(connectTimeout); transitUri = "mysql://" + connectedHost.getHostString() + ":" + connectedHost.getPort(); } catch (IOException | TimeoutException te) { // Try the next host connectedHost = null; transitUri = "<unknown>"; currentHost = (currentHost + 1) % numHosts; connectionAttempts++; lastConnectException = te; } } if (!binlogClient.isConnected()) { binlogClient = null; throw new IOException("Could not connect binlog client to any of the specified hosts due to: " + lastConnectException.getMessage(), lastConnectException); } if (createEnrichmentConnection) { try { jdbcConnection = getJdbcConnection(driverLocation, driverName, connectedHost, username, password, null); } catch (InitializationException | SQLException e) { throw new IOException( "Error creating binlog enrichment JDBC connection to any of the specified hosts", e); } } doStop.set(false); } 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(); // Advance the current binlog position. This way if no more events are received and the processor is stopped, it will resume at the event about to be processed. // We always get ROTATE and FORMAT_DESCRIPTION messages no matter where we start (even from the end), and they won't have the correct "next position" value, so only // advance the position if it is not that type of event. ROTATE events don't generate output CDC events and have the current binlog position in a special field, which // 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 current binlog position. This way if no more events are received and the processor is stopped, it will resume after the event that was just processed. // We always get ROTATE and FORMAT_DESCRIPTION messages no matter where we start (even from the end), and they won't have the correct "next position" value, so only // advance the position if it is not that type of event. if (eventType != ROTATE && eventType != FORMAT_DESCRIPTION) { currentBinlogPosition = header.getNextPosition(); } } } protected void stop(StateManager stateManager) throws CDCException { try { if (binlogClient != null) { binlogClient.disconnect(); } if (eventListener != null) { eventListener.stop(); if (binlogClient != null) { binlogClient.unregisterEventListener(eventListener); } } doStop.set(true); if (hasRun.getAndSet(false)) { updateState(stateManager, currentBinlogFile, currentBinlogPosition, currentSequenceId.get()); } currentBinlogPosition = -1; } catch (IOException e) { throw new CDCException("Error closing CDC connection", e); } finally { binlogClient = null; } } private void updateState(StateManager stateManager, String binlogFile, long binlogPosition, long sequenceId) throws IOException { // Update state with latest values if (stateManager != null) { Map<String, String> newStateMap = new HashMap<>(stateManager.getState(Scope.CLUSTER).toMap()); // Save current binlog filename and position to the state map if (binlogFile != null) { newStateMap.put(BinlogEventInfo.BINLOG_FILENAME_KEY, binlogFile); } newStateMap.put(BinlogEventInfo.BINLOG_POSITION_KEY, Long.toString(binlogPosition)); newStateMap.put(EventWriter.SEQUENCE_ID_KEY, String.valueOf(sequenceId)); stateManager.setState(newStateMap, Scope.CLUSTER); } } /** * Creates and returns a BinlogEventListener instance, associated with the specified binlog client and event queue. * * @param client A reference to a BinaryLogClient. The listener is associated with the given client, such that the listener is notified when * events are available to the given client. * @param q A queue used to communicate events between the listener and the NiFi processor thread. * @return A BinlogEventListener instance, which will be notified of events associated with the specified client */ BinlogEventListener createBinlogEventListener(BinaryLogClient client, LinkedBlockingQueue<RawBinlogEvent> q) { return new BinlogEventListener(client, q); } /** * Creates and returns a BinlogLifecycleListener instance, associated with the specified binlog client and event queue. * * @return A BinlogLifecycleListener instance, which will be notified of events associated with the specified client */ BinlogLifecycleListener createBinlogLifecycleListener() { return new BinlogLifecycleListener(); } BinaryLogClient createBinlogClient(String hostname, int port, String username, String password) { return new BinaryLogClient(hostname, port, username, password); } /** * Retrieves the column information for the specified database and table. The column information can be used to enrich CDC events coming from the RDBMS. * * @param key A TableInfoCacheKey reference, which contains the database and table names * @return A TableInfo instance with the ColumnDefinitions provided (if retrieved successfully from the database) */ protected TableInfo loadTableInfo(TableInfoCacheKey key) throws SQLException { TableInfo tableInfo = null; if (jdbcConnection != null) { try (Statement s = jdbcConnection.createStatement()) { s.execute("USE " + key.getDatabaseName()); ResultSet rs = s.executeQuery("SELECT * FROM " + key.getTableName() + " LIMIT 0"); ResultSetMetaData rsmd = rs.getMetaData(); int numCols = rsmd.getColumnCount(); List<ColumnDefinition> columnDefinitions = new ArrayList<>(); for (int i = 1; i <= numCols; i++) { // Use the column label if it exists, otherwise use the column name. We're not doing aliasing here, but it's better practice. String columnLabel = rsmd.getColumnLabel(i); columnDefinitions.add(new ColumnDefinition(rsmd.getColumnType(i), columnLabel != null ? columnLabel : rsmd.getColumnName(i))); } tableInfo = new TableInfo(key.getDatabaseName(), key.getTableName(), key.getTableId(), columnDefinitions); } } return tableInfo; } /** * using Thread.currentThread().getContextClassLoader(); will ensure that you are using the ClassLoader for you NAR. * * @throws InitializationException if there is a problem obtaining the ClassLoader */ protected Connection getJdbcConnection(String locationString, String drvName, InetSocketAddress host, String username, String password, Map<String, String> customProperties) throws InitializationException, SQLException { Properties connectionProps = new Properties(); if (customProperties != null) { connectionProps.putAll(customProperties); } connectionProps.put("user", username); connectionProps.put("password", password); return DriverManager.getConnection("jdbc:mysql://" + host.getHostString() + ":" + host.getPort(), connectionProps); } protected void registerDriver(String locationString, String drvName) throws InitializationException { if (locationString != null && locationString.length() > 0) { try { // Split and trim the entries final ClassLoader classLoader = ClassLoaderUtils.getCustomClassLoader(locationString, this.getClass().getClassLoader(), (dir, name) -> name != null && name.endsWith(".jar")); // Workaround which allows to use URLClassLoader for JDBC driver loading. // (Because the DriverManager will refuse to use a driver not loaded by the system ClassLoader.) final Class<?> clazz = Class.forName(drvName, true, classLoader); if (clazz == null) { throw new InitializationException("Can't load Database Driver " + drvName); } final Driver driver = (Driver) clazz.newInstance(); DriverManager.registerDriver(new DriverShim(driver)); } catch (final InitializationException e) { throw e; } catch (final MalformedURLException e) { throw new InitializationException("Invalid Database Driver Jar Url", e); } catch (final Exception e) { throw new InitializationException("Can't load Database Driver", e); } } } private static class DriverShim implements Driver { private Driver driver; DriverShim(Driver d) { this.driver = d; } @Override public boolean acceptsURL(String u) throws SQLException { return this.driver.acceptsURL(u); } @Override public Connection connect(String u, Properties p) throws SQLException { return this.driver.connect(u, p); } @Override public int getMajorVersion() { return this.driver.getMajorVersion(); } @Override public int getMinorVersion() { return this.driver.getMinorVersion(); } @Override public DriverPropertyInfo[] getPropertyInfo(String u, Properties p) throws SQLException { return this.driver.getPropertyInfo(u, p); } @Override public boolean jdbcCompliant() { return this.driver.jdbcCompliant(); } @Override public Logger getParentLogger() throws SQLFeatureNotSupportedException { return driver.getParentLogger(); } } }