co.cask.cdap.data.stream.service.upload.FileContentWriterFactory.java Source code

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Here is the source code for co.cask.cdap.data.stream.service.upload.FileContentWriterFactory.java

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/*
 * Copyright  2015 Cask Data, Inc.
 *
 * Licensed 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 co.cask.cdap.data.stream.service.upload;

import co.cask.cdap.data.stream.service.ConcurrentStreamWriter;
import co.cask.cdap.data2.transaction.stream.StreamConfig;
import co.cask.cdap.proto.Id;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.Maps;
import org.apache.twill.filesystem.Location;

import java.io.IOException;
import java.util.Map;

/**
 * A {@link ContentWriterFactory} that creates {@link ContentWriter} that will
 * write events to file directly.
 */
public final class FileContentWriterFactory implements ContentWriterFactory {

    private final StreamConfig streamConfig;
    private final ConcurrentStreamWriter streamWriter;
    private final Map<String, String> headers;
    private final Location streamTmpLocation;

    public FileContentWriterFactory(StreamConfig streamConfig, ConcurrentStreamWriter streamWriter,
            Map<String, String> headers) throws IOException {
        this.streamConfig = streamConfig;
        this.streamWriter = streamWriter;
        this.headers = ImmutableMap.copyOf(headers);

        Location location = streamConfig.getLocation();
        if (location == null) {
            // Should never happen
            throw new IllegalArgumentException("Unknown stream location for stream " + streamConfig.getStreamId());
        }
        this.streamTmpLocation = location.append("tmp");
    }

    @Override
    public Id.Stream getStream() {
        return streamConfig.getStreamId();
    }

    @Override
    public ContentWriter create(Map<String, String> headers) throws IOException {
        Map<String, String> allHeaders = Maps.newHashMap(this.headers);
        allHeaders.putAll(headers);
        Location uploadDir = streamTmpLocation.append("upload")
                .getTempFile(Long.toString(System.currentTimeMillis()));
        uploadDir.mkdirs();
        return new FileContentWriter(streamConfig, streamWriter, uploadDir, allHeaders);
    }
}