QueryResponseTransformerProducer.java

/**
 * Copyright (c) Codice Foundation
 * <p>
 * This is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser
 * General Public License as published by the Free Software Foundation, either version 3 of the
 * License, or any later version.
 * <p>
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
 * even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details. A copy of the GNU Lesser General Public License
 * is distributed along with this program and can be found at
 * <http://www.gnu.org/licenses/lgpl.html>.
 */
package ddf.camel.component.catalog.queryresponsetransformer;

import java.io.Serializable;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;

import javax.activation.MimeType;
import javax.activation.MimeTypeParseException;

import org.apache.camel.Message;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import ddf.camel.component.catalog.CatalogEndpoint;
import ddf.camel.component.catalog.transformer.TransformerProducer;
import ddf.catalog.operation.SourceResponse;
import ddf.catalog.transform.CatalogTransformerException;
import ddf.catalog.transform.QueryResponseTransformer;
import ddf.mime.MimeTypeToTransformerMapper;

/**
 * Producer for the custom Camel CatalogComponent. This {@link org.apache.camel.Producer} would map
 * to a Camel <to> route node with a URI like <code>catalog:queryresponsetransformer</code>
 *
 * @author William Miller, Lockheed Martin
 * @author ddf.isgs@lmco.com
 *
 */
public class QueryResponseTransformerProducer extends TransformerProducer {
    private static final transient Logger LOGGER = LoggerFactory.getLogger(
            QueryResponseTransformerProducer.class);

    /**
     * Constructs the {@link Producer} for the custom Camel CatalogComponent. This producer would
     * map to a Camel <to> route node with a URI like <code>catalog:queryresponsetransformer</code>
     *
     * @param endpoint
     *            the Camel endpoint that created this consumer
     */
    public QueryResponseTransformerProducer(CatalogEndpoint endpoint) {
        super(endpoint);
    }

    protected Object transform(Message in, Object obj, String mimeType, String transformerId,
            MimeTypeToTransformerMapper mapper)
            throws MimeTypeParseException, CatalogTransformerException {
        // Look up the QueryResponseTransformer for the request's mime type.
        // If a transformer is found, then transform the request's payload into a BinaryContent
        // Otherwise, throw an exception.
        MimeType derivedMimeType = new MimeType(mimeType);

        if (transformerId != null) {
            derivedMimeType = new MimeType(
                    mimeType + ";" + MimeTypeToTransformerMapper.ID_KEY + "=" + transformerId);
        }

        List<QueryResponseTransformer> matches = mapper.findMatches(QueryResponseTransformer.class,
                derivedMimeType);
        Object binaryContent = null;

        if (matches != null && matches.size() == 1) {
            Map<String, Serializable> arguments = new HashMap<String, Serializable>();
            for (Entry<String, Object> entry : in.getHeaders()
                    .entrySet()) {
                if (entry.getValue() instanceof Serializable) {
                    arguments.put(entry.getKey(), (Serializable) entry.getValue());
                }
            }

            LOGGER.debug("Found a matching QueryResponseTransformer for [{}]", transformerId);
            QueryResponseTransformer transformer = matches.get(0);
            SourceResponse srcResp = in.getBody(SourceResponse.class);
            if (null != srcResp) {
                binaryContent = transformer.transform(srcResp, arguments);
            }
        } else {
            LOGGER.debug("Did not find an QueryResponseTransformer for [{}]", transformerId);
            throw new CatalogTransformerException(
                    "Did not find an QueryResponseTransformer for [" + transformerId + "]");
        }
        return binaryContent;
    }

}