Github user rmetzger commented on a diff in the pull request: https://github.com/apache/flink/pull/1580#discussion_r52022185 --- Diff: flink-streaming-connectors/flink-connector-redis/src/main/java/org/apache/flink/streaming/connectors/redis/RedisSink.java --- @@ -0,0 +1,160 @@ +/* + * 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.flink.streaming.connectors.redis; + +import org.apache.flink.configuration.Configuration; +import org.apache.flink.streaming.api.functions.sink.RichSinkFunction; +import org.apache.flink.streaming.util.serialization.SerializationSchema; + +import redis.clients.jedis.Jedis; +import redis.clients.jedis.JedisPool; +import redis.clients.jedis.JedisPoolConfig; +import redis.clients.jedis.Protocol; +import redis.clients.jedis.exceptions.JedisException; + +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import com.google.common.base.Preconditions; + +/** + * A sink that delivers data to a Redis channel using the Jedis client. + * + * <p> + * When creating the sink {@code host, port, schema} must be specified or else it will throw + * {@link NullPointerException} + * + * * <p> + * Example: + * + * <pre>{@code + * new RedisSink<String>(host, port, schema) + * }</pre> + * + * @param <IN> Type of the elements emitted by this sink + */ +public class RedisSink<IN> extends RichSinkFunction<IN> { + + private static final long serialVersionUID = 1L; + private static final Logger LOG = LoggerFactory.getLogger(RedisSink.class); + + private static final int DEFAULT_TIMEOUT = 2000; + + private String host; + private int port; + private String channel; + private int timeOut; + private int soTimeOut; + private int database; + private String password; + private String clientName; + + private SerializationSchema<IN> schema; + private transient JedisPoolConfig poolConfig; + private transient JedisPool jedisPool; + + /** + * Creates a new RedisSink. For passing custom connection Pool config, please use the constructor + * {@link RedisSink#RedisSink(String, int, String, SerializationSchema, int, int, String, int, String, + * JedisPoolConfig poolConfig)}, + * @param host Redis Host name to connect to + * @param port Redis instance Port + * @param channel The channel to which data will be published + * @param schema A {@link SerializationSchema} for turning the java object to bytes. + */ + public RedisSink(String host, int port, String channel, SerializationSchema<IN> schema) { + this(host, port, channel, schema, DEFAULT_TIMEOUT, DEFAULT_TIMEOUT, null, Protocol.DEFAULT_DATABASE, null, null); + } + + /** + * Creates a new RedisSink. + * @param host Redis Host name to connect to + * @param port Redis instance Port + * @param channel The channel to which data will be published + * @param schema A {@link SerializationSchema} for turning the java object to bytes. + * @param timeOut Connection Timeout in millisecond + * @param soTimeOut Socket Timeout in millisecond. Sets Socket::SO_TIMEOUT + * @param password Password for Redis Server + * @param database Select the DB with having the specified zero-based numeric index + * @param clientName Assigns a name to the current connection using CLIENT SETNAME command + * @param poolConfig Custom jedis connection pool configuration + */ + public RedisSink(String host, int port, String channel, SerializationSchema<IN> schema, int timeOut, + int soTimeOut, String password, int database, String clientName, JedisPoolConfig poolConfig) { + + Preconditions.checkNotNull(host, "Redis host name should not be Null"); + Preconditions.checkNotNull(channel, "Redis Channel name can not be null"); + Preconditions.checkNotNull(schema, "SerializationSchema should not be Null"); + + this.host = host; + this.port = port; + this.channel = channel; + this.schema = schema; + this.timeOut = timeOut; + this.soTimeOut = soTimeOut; + this.password = password; + this.database = database; + this.clientName = clientName; + this.poolConfig = poolConfig; + } + + /** + * Called when new data arrives to the sink, and forwards it to Redis channel. + * + * @param value The incoming data + */ + @Override + public void invoke(IN value) throws Exception { + try (Jedis jedis = jedisPool.getResource()) { + byte[] msg = schema.serialize(value); + jedis.publish(channel.getBytes(), msg); + } catch (Exception e) { + if (LOG.isErrorEnabled()) { + LOG.error("Cannot send Redis message {}", channel); --- End diff -- You should log the exception as well! It would be helpful to add a flag which controls the error behavior. Some users want their system to fail with an exception if its unable to deliver a message (Flink's fault tolerance would restart the job and retry!)
--- If your project is set up for it, you can reply to this email and have your reply appear on GitHub as well. If your project does not have this feature enabled and wishes so, or if the feature is enabled but not working, please contact infrastructure at infrastruct...@apache.org or file a JIRA ticket with INFRA. ---