org.apache.samza.system.kinesis.descriptors.KinesisInputDescriptor.java Source code

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Here is the source code for org.apache.samza.system.kinesis.descriptors.KinesisInputDescriptor.java

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/*
 * 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.samza.system.kinesis.descriptors;

import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import java.util.Optional;

import org.apache.commons.lang3.StringUtils;
import org.apache.samza.serializers.KVSerde;
import org.apache.samza.serializers.NoOpSerde;
import org.apache.samza.serializers.Serde;
import org.apache.samza.system.descriptors.InputDescriptor;
import org.apache.samza.system.descriptors.SystemDescriptor;
import org.apache.samza.system.kinesis.KinesisConfig;

/**
 * A {@link KinesisInputDescriptor} can be used for specifying Samza and Kinesis specific properties of Kinesis
 * input streams.
 * <p>
 * Use {@link KinesisSystemDescriptor#getInputDescriptor} to obtain an instance of this descriptor.
 * <p>
 * Stream properties provided in configuration override corresponding properties specified using a descriptor.
 *
 * @param <StreamMessageType> type of messages in this stream
 */
public class KinesisInputDescriptor<StreamMessageType>
        extends InputDescriptor<StreamMessageType, KinesisInputDescriptor<StreamMessageType>> {
    private Optional<String> accessKey = Optional.empty();
    private Optional<String> secretKey = Optional.empty();
    private Optional<String> region = Optional.empty();
    private Map<String, String> kclConfig = Collections.emptyMap();

    /**
     * Constructs an {@link InputDescriptor} instance.
     *
     * @param streamId id of the stream
     * @param valueSerde serde the values in the messages in the stream
     * @param systemDescriptor system descriptor this stream descriptor was obtained from
     */
    <T> KinesisInputDescriptor(String streamId, Serde<T> valueSerde, SystemDescriptor systemDescriptor) {
        super(streamId, KVSerde.of(new NoOpSerde<>(), valueSerde), systemDescriptor, null);
    }

    /**
     * Kinesis region for the system stream.
     * @param region Kinesis region
     * @return this input descriptor
     */
    public KinesisInputDescriptor<StreamMessageType> withRegion(String region) {
        this.region = Optional.ofNullable(StringUtils.stripToNull(region));
        return this;
    }

    /**
     * Kinesis access key name for the system stream.
     * @param accessKey Kinesis access key name
     * @return this input descriptor
     */
    public KinesisInputDescriptor<StreamMessageType> withAccessKey(String accessKey) {
        this.accessKey = Optional.ofNullable(StringUtils.stripToNull(accessKey));
        return this;
    }

    /**
     * Kinesis secret key name for the system stream.
     * @param secretKey Kinesis secret key
     * @return this input descriptor
     */
    public KinesisInputDescriptor<StreamMessageType> withSecretKey(String secretKey) {
        this.secretKey = Optional.ofNullable(StringUtils.stripToNull(secretKey));
        return this;
    }

    /**
     * KCL (Kinesis Client Library) config for the system stream. This is not required by default.
     * @param kclConfig A map of specified KCL configs
     * @return this input descriptor
     */
    public KinesisInputDescriptor<StreamMessageType> withKCLConfig(Map<String, String> kclConfig) {
        this.kclConfig = kclConfig;
        return this;
    }

    @Override
    public Map<String, String> toConfig() {
        Map<String, String> config = new HashMap<>(super.toConfig());

        String systemName = getSystemName();
        String streamId = getStreamId();
        String clientConfigPrefix = String.format(KinesisConfig.CONFIG_STREAM_KINESIS_CLIENT_LIB_CONFIG, systemName,
                streamId);

        region.ifPresent(
                val -> config.put(String.format(KinesisConfig.CONFIG_STREAM_REGION, systemName, streamId), val));
        accessKey.ifPresent(val -> config
                .put(String.format(KinesisConfig.CONFIG_STREAM_ACCESS_KEY, systemName, streamId), val));
        secretKey.ifPresent(val -> config
                .put(String.format(KinesisConfig.CONFIG_STREAM_SECRET_KEY, systemName, streamId), val));
        kclConfig.forEach((k, v) -> config.put(clientConfigPrefix + k, v));

        return config;
    }
}