src/main/java/org/apache/rocketmq/flink/source/table/RocketMQScanTableSource.java

/*
 * 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.rocketmq.flink.source.table;

import org.apache.rocketmq.flink.legacy.RocketMQConfig;
import org.apache.rocketmq.flink.legacy.RocketMQSourceFunction;
import org.apache.rocketmq.flink.legacy.common.serialization.KeyValueDeserializationSchema;
import org.apache.rocketmq.flink.legacy.common.serialization.RowKeyValueDeserializationSchema;
import org.apache.rocketmq.flink.source.RocketMQSource;
import org.apache.rocketmq.flink.source.reader.deserializer.BytesMessage;
import org.apache.rocketmq.flink.source.reader.deserializer.RocketMQDeserializationSchema;
import org.apache.rocketmq.flink.source.reader.deserializer.RocketMQRowDeserializationSchema;
import org.apache.rocketmq.flink.source.reader.deserializer.RowDeserializationSchema.MetadataConverter;

import org.apache.flink.table.api.DataTypes;
import org.apache.flink.table.api.TableSchema;
import org.apache.flink.table.connector.ChangelogMode;
import org.apache.flink.table.connector.source.DynamicTableSource;
import org.apache.flink.table.connector.source.ScanTableSource;
import org.apache.flink.table.connector.source.SourceFunctionProvider;
import org.apache.flink.table.connector.source.SourceProvider;
import org.apache.flink.table.connector.source.abilities.SupportsReadingMetadata;
import org.apache.flink.table.data.RowData;
import org.apache.flink.table.data.StringData;
import org.apache.flink.table.descriptors.DescriptorProperties;
import org.apache.flink.table.types.DataType;

import java.util.Collections;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Properties;
import java.util.stream.Stream;

import static org.apache.flink.api.connector.source.Boundedness.BOUNDED;
import static org.apache.flink.api.connector.source.Boundedness.CONTINUOUS_UNBOUNDED;

/** Defines the scan table source of RocketMQ. */
public class RocketMQScanTableSource implements ScanTableSource, SupportsReadingMetadata {

    private final DescriptorProperties properties;
    private final TableSchema schema;

    private final String consumerOffsetMode;
    private final long consumerOffsetTimestamp;

    private final String topic;
    private final String consumerGroup;
    private final String nameServerAddress;
    private final String tag;
    private final String sql;

    private final String accessKey;
    private final String secretKey;

    private final long stopInMs;
    private final long partitionDiscoveryIntervalMs;
    private final long startMessageOffset;
    private final long startTime;
    private final boolean useNewApi;

    private List<String> metadataKeys;

    public RocketMQScanTableSource(
            DescriptorProperties properties,
            TableSchema schema,
            String topic,
            String consumerGroup,
            String nameServerAddress,
            String accessKey,
            String secretKey,
            String tag,
            String sql,
            long stopInMs,
            long startMessageOffset,
            long startTime,
            long partitionDiscoveryIntervalMs,
            String consumerOffsetMode,
            long consumerOffsetTimestamp,
            boolean useNewApi) {
        this.properties = properties;
        this.schema = schema;
        this.topic = topic;
        this.consumerGroup = consumerGroup;
        this.nameServerAddress = nameServerAddress;
        this.accessKey = accessKey;
        this.secretKey = secretKey;
        this.tag = tag;
        this.sql = sql;
        this.stopInMs = stopInMs;
        this.startMessageOffset = startMessageOffset;
        this.startTime = startTime;
        this.partitionDiscoveryIntervalMs = partitionDiscoveryIntervalMs;
        this.useNewApi = useNewApi;
        this.metadataKeys = Collections.emptyList();
        this.consumerOffsetMode = consumerOffsetMode;
        this.consumerOffsetTimestamp = consumerOffsetTimestamp;
    }

    @Override
    public ChangelogMode getChangelogMode() {
        return ChangelogMode.insertOnly();
    }

    @Override
    public ScanRuntimeProvider getScanRuntimeProvider(ScanContext scanContext) {
        if (useNewApi) {
            return SourceProvider.of(
                    new RocketMQSource<>(
                            topic,
                            consumerGroup,
                            nameServerAddress,
                            accessKey,
                            secretKey,
                            tag,
                            sql,
                            stopInMs,
                            startTime,
                            startMessageOffset < 0 ? 0 : startMessageOffset,
                            partitionDiscoveryIntervalMs,
                            isBounded() ? BOUNDED : CONTINUOUS_UNBOUNDED,
                            createRocketMQDeserializationSchema(),
                            consumerOffsetMode,
                            consumerOffsetTimestamp));
        } else {
            return SourceFunctionProvider.of(
                    new RocketMQSourceFunction<>(
                            createKeyValueDeserializationSchema(), getConsumerProps()),
                    isBounded());
        }
    }

    @Override
    public Map<String, DataType> listReadableMetadata() {
        final Map<String, DataType> metadataMap = new LinkedHashMap<>();
        Stream.of(ReadableMetadata.values())
                .forEachOrdered(m -> metadataMap.putIfAbsent(m.key, m.dataType));
        return metadataMap;
    }

    @Override
    public void applyReadableMetadata(List<String> metadataKeys, DataType producedDataType) {
        this.metadataKeys = metadataKeys;
    }

    @Override
    public DynamicTableSource copy() {
        RocketMQScanTableSource tableSource =
                new RocketMQScanTableSource(
                        properties,
                        schema,
                        topic,
                        consumerGroup,
                        nameServerAddress,
                        accessKey,
                        secretKey,
                        tag,
                        sql,
                        stopInMs,
                        startMessageOffset,
                        startTime,
                        partitionDiscoveryIntervalMs,
                        consumerOffsetMode,
                        consumerOffsetTimestamp,
                        useNewApi);
        tableSource.metadataKeys = metadataKeys;
        return tableSource;
    }

    @Override
    public String asSummaryString() {
        return RocketMQScanTableSource.class.getName();
    }

    private RocketMQDeserializationSchema<RowData> createRocketMQDeserializationSchema() {
        final MetadataConverter[] metadataConverters =
                metadataKeys.stream()
                        .map(
                                k ->
                                        Stream.of(ReadableMetadata.values())
                                                .filter(rm -> rm.key.equals(k))
                                                .findFirst()
                                                .orElseThrow(IllegalStateException::new))
                        .map(m -> m.converter)
                        .toArray(MetadataConverter[]::new);
        return new RocketMQRowDeserializationSchema(
                schema, properties.asMap(), metadataKeys.size() > 0, metadataConverters);
    }

    private boolean isBounded() {
        return stopInMs != Long.MAX_VALUE;
    }

    private KeyValueDeserializationSchema<RowData> createKeyValueDeserializationSchema() {
        return new RowKeyValueDeserializationSchema.Builder()
                .setProperties(properties.asMap())
                .setTableSchema(schema)
                .build();
    }

    private Properties getConsumerProps() {
        Properties consumerProps = new Properties();
        consumerProps.setProperty(RocketMQConfig.CONSUMER_TOPIC, topic);
        consumerProps.setProperty(RocketMQConfig.CONSUMER_GROUP, consumerGroup);
        consumerProps.setProperty(RocketMQConfig.NAME_SERVER_ADDR, nameServerAddress);
        consumerProps.setProperty(RocketMQConfig.CONSUMER_TAG, tag);
        consumerProps.setProperty(RocketMQConfig.CONSUMER_SQL, sql);
        consumerProps.setProperty(
                RocketMQConfig.CONSUMER_START_MESSAGE_OFFSET, String.valueOf(startMessageOffset));
        consumerProps.setProperty(RocketMQConfig.ACCESS_KEY, accessKey);
        consumerProps.setProperty(RocketMQConfig.SECRET_KEY, secretKey);
        return consumerProps;
    }

    // --------------------------------------------------------------------------------------------
    // Metadata handling
    // --------------------------------------------------------------------------------------------

    enum ReadableMetadata {
        TOPIC(
                "topic",
                DataTypes.STRING().notNull(),
                new MetadataConverter() {
                    private static final long serialVersionUID = 1L;

                    @Override
                    public Object read(BytesMessage message) {
                        return StringData.fromString(
                                String.valueOf(message.getProperty("__topic__")));
                    }
                });

        final String key;

        final DataType dataType;

        final MetadataConverter converter;

        ReadableMetadata(String key, DataType dataType, MetadataConverter converter) {
            this.key = key;
            this.dataType = dataType;
            this.converter = converter;
        }
    }
}