| /* |
| * 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.rya.test.kafka; |
| |
| import static java.util.Objects.requireNonNull; |
| |
| import java.util.ArrayList; |
| import java.util.List; |
| import java.util.Properties; |
| import java.util.UUID; |
| |
| import org.apache.kafka.clients.consumer.Consumer; |
| import org.apache.kafka.clients.consumer.ConsumerConfig; |
| import org.apache.kafka.clients.consumer.ConsumerRecord; |
| import org.apache.kafka.clients.consumer.KafkaConsumer; |
| import org.apache.kafka.clients.producer.KafkaProducer; |
| import org.apache.kafka.clients.producer.Producer; |
| import org.apache.kafka.clients.producer.ProducerConfig; |
| import org.apache.kafka.common.serialization.Deserializer; |
| import org.apache.kafka.common.serialization.Serializer; |
| |
| import edu.umd.cs.findbugs.annotations.DefaultAnnotation; |
| import edu.umd.cs.findbugs.annotations.NonNull; |
| |
| /** |
| * A set of utility functions that are useful when writing tests against a Kafka instance. |
| */ |
| @DefaultAnnotation(NonNull.class) |
| public final class KafkaTestUtil { |
| |
| private KafkaTestUtil() { } |
| |
| /** |
| * Create a {@link Producer} that is able to write to a topic that is hosted within an embedded instance of Kafka. |
| * |
| * @param kafka - The Kafka rule used to connect to the embedded Kafka instance. (not null) |
| * @param keySerializerClass - Serializes the keys. (not null) |
| * @param valueSerializerClass - Serializes the values. (not null) |
| * @return A {@link Producer} that can be used to write records to a topic. |
| */ |
| public static <K, V> Producer<K, V> makeProducer( |
| final KafkaTestInstanceRule kafka, |
| final Class<? extends Serializer<K>> keySerializerClass, |
| final Class<? extends Serializer<V>> valueSerializerClass) { |
| requireNonNull(kafka); |
| requireNonNull(keySerializerClass); |
| requireNonNull(valueSerializerClass); |
| |
| final Properties props = kafka.createBootstrapServerConfig(); |
| props.setProperty(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG, keySerializerClass.getName()); |
| props.setProperty(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG, valueSerializerClass.getName()); |
| return new KafkaProducer<>(props); |
| } |
| |
| /** |
| * Create a {@link Consumer} that has a unique group ID and reads everything from a topic that is hosted within an |
| * embedded instance of Kafka starting at the earliest point by default. |
| * |
| * @param kafka - The Kafka rule used to connect to the embedded Kafka instance. (not null) |
| * @param keyDeserializerClass - Deserializes the keys. (not null) |
| * @param valueDeserializerClass - Deserializes the values. (not null) |
| * @return A {@link Consumer} that can be used to read records from a topic. |
| */ |
| public static <K, V> Consumer<K, V> fromStartConsumer( |
| final KafkaTestInstanceRule kafka, |
| final Class<? extends Deserializer<K>> keyDeserializerClass, |
| final Class<? extends Deserializer<V>> valueDeserializerClass) { |
| requireNonNull(kafka); |
| requireNonNull(keyDeserializerClass); |
| requireNonNull(valueDeserializerClass); |
| |
| final Properties props = kafka.createBootstrapServerConfig(); |
| props.setProperty(ConsumerConfig.GROUP_ID_CONFIG, UUID.randomUUID().toString()); |
| props.setProperty(ConsumerConfig.CLIENT_ID_CONFIG, UUID.randomUUID().toString()); |
| props.setProperty(ConsumerConfig.AUTO_OFFSET_RESET_CONFIG, "earliest"); |
| props.setProperty(ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, keyDeserializerClass.getName()); |
| props.setProperty(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, valueDeserializerClass.getName()); |
| return new KafkaConsumer<>(props); |
| } |
| |
| /** |
| * Polls a {@link Consumer} until it has either polled too many times without hitting the target number |
| * of results, or it hits the target number of results. |
| * |
| * @param pollMs - How long each poll could take. |
| * @param pollIterations - The maximum number of polls that will be attempted. |
| * @param targetSize - The number of results to read before stopping. |
| * @param consumer - The consumer that will be polled. |
| * @return The results that were read from the consumer. |
| * @throws Exception If the poll failed. |
| */ |
| public static <K, V> List<V> pollForResults( |
| final int pollMs, |
| final int pollIterations, |
| final int targetSize, |
| final Consumer<K, V> consumer) throws Exception { |
| requireNonNull(consumer); |
| |
| final List<V> values = new ArrayList<>(); |
| |
| int i = 0; |
| while(values.size() < targetSize && i < pollIterations) { |
| for(final ConsumerRecord<K, V> record : consumer.poll(pollMs)) { |
| values.add( record.value() ); |
| } |
| i++; |
| } |
| |
| return values; |
| } |
| } |