src/main/java/org/apache/flume/http/source/BLOBHandler.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.flume.http.source;

import java.io.InputStream;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.apache.commons.io.IOUtils;
import org.apache.commons.io.output.ByteArrayOutputStream;
import org.apache.flume.Context;
import org.apache.flume.Event;
import org.apache.flume.conf.LogPrivacyUtil;
import org.apache.flume.event.EventBuilder;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.google.common.base.Preconditions;

import jakarta.servlet.http.HttpServletRequest;

/**
 *
 * BLOBHandler for HTTPSource that accepts any binary stream of data as event.
 *
 */
public class BLOBHandler implements HTTPSourceHandler {

    private static final Logger LOG = LoggerFactory.getLogger(BLOBHandler.class);

    private String commaSeparatedHeaders;

    private String[] mandatoryHeaders;

    public static final String MANDATORY_PARAMETERS = "mandatoryParameters";

    public static final String DEFAULT_MANDATORY_PARAMETERS = "";

    public static final String PARAMETER_SEPARATOR = ",";

    /**
     * {@inheritDoc}
     */
    @SuppressWarnings("unchecked")
    @Override
    public List<Event> getEvents(HttpServletRequest request) throws Exception {
        Map<String, String> headers = new HashMap<String, String>();

        InputStream inputStream = request.getInputStream();

        Map<String, String[]> parameters = request.getParameterMap();
        for (String parameter : parameters.keySet()) {
            String value = parameters.get(parameter)[0];
            if (LOG.isDebugEnabled() && LogPrivacyUtil.allowLogRawData()) {
                LOG.debug("Setting Header [Key, Value] as [{},{}] ", parameter, value);
            }
            headers.put(parameter, value);
        }

        for (String header : mandatoryHeaders) {
            Preconditions.checkArgument(
                    headers.containsKey(header), "Please specify " + header + " parameter in the request.");
        }

        ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
        try {
            IOUtils.copy(inputStream, outputStream);
            LOG.debug("Building an Event with stream of size -- {}", outputStream.size());
            Event event = EventBuilder.withBody(outputStream.toByteArray(), headers);
            event.setHeaders(headers);
            List<Event> eventList = new ArrayList<Event>();
            eventList.add(event);
            return eventList;
        } finally {
            outputStream.close();
            inputStream.close();
        }
    }

    @Override
    public void configure(Context context) {
        this.commaSeparatedHeaders = context.getString(MANDATORY_PARAMETERS, DEFAULT_MANDATORY_PARAMETERS);
        this.mandatoryHeaders = commaSeparatedHeaders.split(PARAMETER_SEPARATOR);
    }
}