gerdansantos commented on a change in pull request #4065: NIFI-4239 - Adding CaptureChangePostgreSQL processor to capture data changes (INSERT/UPDATE/DELETE) in PostgreSQL tables via Logical Replication. URL: https://github.com/apache/nifi/pull/4065#discussion_r383635285
########## File path: nifi-nar-bundles/nifi-cdc/nifi-cdc-postgresql-bundle/nifi-cdc-postgresql-processors/src/main/java/org/apache/nifi/cdc/postgresql/processors/CaptureChangePostgreSQL.java ########## @@ -0,0 +1,519 @@ +/* + * 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.postgresql.processors; + +import java.io.IOException; +import java.io.OutputStream; +import java.net.MalformedURLException; +import java.nio.charset.StandardCharsets; +import java.sql.Connection; +import java.sql.Driver; +import java.sql.DriverManager; +import java.sql.DriverPropertyInfo; +import java.sql.SQLException; +import java.sql.SQLFeatureNotSupportedException; +import java.util.ArrayList; +import java.util.Collections; +import java.util.HashMap; +import java.util.HashSet; +import java.util.LinkedList; +import java.util.List; +import java.util.Map; +import java.util.Properties; +import java.util.Set; +import java.util.concurrent.atomic.AtomicBoolean; +import java.util.logging.Logger; + +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.OnScheduled; +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.postgresql.pgEasyReplication.ConnectionManager; +import org.apache.nifi.cdc.postgresql.pgEasyReplication.PGEasyReplication; +import org.apache.nifi.cdc.postgresql.pgEasyReplication.Event; +import org.apache.nifi.components.PropertyDescriptor; +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.expression.ExpressionLanguageScope; +import org.apache.nifi.flowfile.FlowFile; +import org.apache.nifi.logging.ComponentLog; +import org.apache.nifi.processor.AbstractProcessor; +import org.apache.nifi.processor.ProcessContext; +import org.apache.nifi.processor.ProcessSession; +import org.apache.nifi.processor.ProcessorInitializationContext; +import org.apache.nifi.processor.Relationship; +import org.apache.nifi.processor.exception.ProcessException; +import org.apache.nifi.processor.io.OutputStreamCallback; +import org.apache.nifi.processor.util.StandardValidators; +import org.apache.nifi.reporting.InitializationException; +import org.apache.nifi.util.file.classloader.ClassLoaderUtils; + +/** + * 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", "postgresql" }) +@CapabilityDescription("Retrieves Change Data Capture (CDC) events from a PostgreSQL database. CDC Events include INSERT, UPDATE, DELETE operations. Events " + + "are output as individual flow files ordered by the time at which the operation occurred. This processor use a replication connection to stream data and sql connection to snapshot.") +@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 = "last.lsn.received", description = "A Log Sequence Number (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 = "mime.type", description = "The processor outputs flow file content in JSON format, and sets the mime.type attribute to " + "application/json") }) + +public class CaptureChangePostgreSQL extends AbstractProcessor { + // Relationships + public static final Relationship REL_SUCCESS = new Relationship.Builder().name("success").description("Successfully created FlowFile from CDC event.").build(); + // Properties + public static final PropertyDescriptor HOST = new PropertyDescriptor.Builder() + .name("cdc-postgresql-host") + .displayName("PostgreSQL Host") + .description("A list of hostname/port entries corresponding to nodes in a PostgreSQL cluster. The entries should be comma separated " + + "using a colon such as host1:port,host2:port,.... For example postgresql.myhost.com:5432. 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 PostgreSQL connections is 5432.") + .required(true) + .addValidator(StandardValidators.NON_EMPTY_VALIDATOR) + .build(); + + public static final PropertyDescriptor DRIVER_NAME = new PropertyDescriptor.Builder() + .name("cdc-postgresql-driver-class") + .displayName("PostgreSQL Driver Class Name") + .description("The class name of the PostgreSQL database driver class") + .defaultValue("org.postgresql.Driver") + .required(true) + .addValidator(StandardValidators.NON_EMPTY_VALIDATOR) + .expressionLanguageSupported(ExpressionLanguageScope.VARIABLE_REGISTRY) + .build(); + + public static final PropertyDescriptor DRIVER_LOCATION = new PropertyDescriptor.Builder() + .name("cdc-postgresql-driver-locations") + .displayName("PostgreSQL Driver Location(s)") + .description("Comma-separated list of files/folders and/or URLs containing the PostgreSQL driver JAR and its dependencies (if any)." + + "For example '/var/tmp/postgresql-42.2.9.jar'") + .defaultValue(null) + .required(false) + .addValidator(StandardValidators.createListValidator(true, true, StandardValidators.createURLorFileValidator())) + .expressionLanguageSupported(ExpressionLanguageScope.VARIABLE_REGISTRY) + .build(); + + public static final PropertyDescriptor DATABASE_NAME = new PropertyDescriptor.Builder() + .name("cdc-postgresql-database") + .displayName("Database") + .description("Specifies the name of the database to connect to.") + .required(true) + .addValidator(StandardValidators.NON_EMPTY_VALIDATOR).build(); + + public static final PropertyDescriptor USERNAME = new PropertyDescriptor.Builder() + .name("cdc-postgresql-user") + .displayName("Username") + .description("Username to access PostgreSQL cluster.") + .required(true) + .addValidator(StandardValidators.NON_EMPTY_VALIDATOR) + .build(); + + public static final PropertyDescriptor PASSWORD = new PropertyDescriptor.Builder() + .name("cdc-postgresql-password") + .displayName("Password") + .description("Password to access PostgreSQL cluster.") + .required(false) + .sensitive(true) + .addValidator(StandardValidators.NON_EMPTY_VALIDATOR) + .build(); + + public static final PropertyDescriptor PUBLICATION = new PropertyDescriptor.Builder() + .name("cdc-postgresql-publication") + .displayName("Publication") + .description("PostgreSQL publication name. A publication is essentially a group of tables whose data changes are intended to be replicated through logical replication.") + .required(true) + .addValidator(StandardValidators.NON_EMPTY_VALIDATOR) + .build(); + + public static final PropertyDescriptor SLOT_NAME = new PropertyDescriptor.Builder() + .name("cdc-postgresql-slot-name") + .displayName("Slot Name") + .description("A unique, cluster-wide identifier for the replication slot") + .required(true) + .addValidator(StandardValidators.NON_EMPTY_VALIDATOR) + .build(); + + public static final PropertyDescriptor SNAPSHOT = new PropertyDescriptor.Builder() + .name("cdc-postgresql-snapshot") + .displayName("Make Snapshot") + .description("The initial data in existing subscribed tables are snapshotted and copied in a parallel instance of a special kind of apply " + + "process. This process will create its own temporary replication slot and copy the existing data. Once existing data is copied, " + + "the worker enters synchronization mode, which ensures that the table is brought up to a synchronized state with the main apply " + + "process by streaming any changes that happened during the initial data copy using standard logical replication. Once the " + + "synchronization is done, the control of the replication of the table is given back to the main apply process where the replication " + "continues as normal.") + .required(true) + .allowableValues("true", "false") + .defaultValue("false") + .addValidator(StandardValidators.BOOLEAN_VALIDATOR) + .build(); + + public static final PropertyDescriptor INCLUDE_BEGIN_COMMIT = new PropertyDescriptor.Builder() + .name("cdc-postgresql-include-begin-commit") + .displayName("Include Begin/Commit Events") + .description("Specifies whether to emit events corresponding to a BEGIN or COMMIT event. 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 INIT_LSN = new PropertyDescriptor.Builder() + .name("cdc-postgresql-init-lsn") + .displayName("Initial Log Sequence Number - LSN") + .description("Specifies an initial Log Sequence Number - LSN to use if this processor's State does not have a current " + + "sequence identifier. If a Log Sequence Number - LSN is present in the processor's State, this property is ignored. Log Sequence Number - LSN 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.POSITIVE_LONG_VALIDATOR) + .build(); + + public static final PropertyDescriptor DROP_SLOT_IF_EXISTS = new PropertyDescriptor.Builder() + .name("cdc-postgresql-drop-slot-if-exists") + .displayName("Drop If Exists Replication Slot") + .description("The initial data in existing subscribed tables are snapshotted and copied in a parallel instance of a special kind of apply " + + "process. This process will create its own temporary replication slot and copy the existing data. Once existing data is copied, " + + "the worker enters synchronization mode, which ensures that the table is brought up to a synchronized state with the main apply " + + "process by streaming any changes that happened during the initial data copy using standard logical replication. Once the " + + "synchronization is done, the control of the replication of the table is given back to the main apply process where the replication " + "continues as normal.") + .required(true) + .allowableValues("true", "false") + .defaultValue("false") + .addValidator(StandardValidators.BOOLEAN_VALIDATOR) + .build(); + + private List<PropertyDescriptor> descriptors; + private Set<Relationship> relationships; + + // Attribute keys + public static final String MIME_TYPE_ATTRIBUTE = "mime.type"; Review comment: Done. ``` +import org.apache.nifi.flowfile.attributes.CoreAttributes; // Attribute keys - public static final String MIME_TYPE_ATTRIBUTE = "mime.type"; -flowFile = session.putAttribute(flowFile, MIME_TYPE_ATTRIBUTE, MIME_TYPE_VALUE); +flowFile = session.putAttribute(flowFile, CoreAttributes.MIME_TYPE.key(), MIME_TYPE_VALUE); ``` ---------------------------------------------------------------- This is an automated message from the Apache Git Service. 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