org.grycap.gpf4med.DocumentFetcher.java Source code

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Here is the source code for org.grycap.gpf4med.DocumentFetcher.java

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/*
 * Copyright 2013 Institute for Molecular Imaging Instrumentation (I3M)
 * 
 * Licensed under the EUPL, Version 1.1 or - as soon they will be approved by 
 * the European Commission - subsequent versions of the EUPL (the "Licence");
 * You may not use this work except in compliance with the Licence.
 * You may obtain a copy of the Licence at:
 * 
 *   http://ec.europa.eu/idabc/eupl
 * 
 * Unless required by applicable law or agreed to in writing, software 
 * distributed under the Licence is distributed on an "AS IS" basis,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the Licence for the specific language governing permissions and 
 * limitations under the Licence.
 * 
 * This product combines work with different licenses. See the "NOTICE" text
 * file for details on the various modules and licenses.
 * The "NOTICE" text file is part of the distribution. Any derivative works
 * that you distribute must include a readable copy of the "NOTICE" text file.
 */

package org.grycap.gpf4med;

import static com.google.common.base.Preconditions.checkArgument;

import java.io.File;
import java.net.URI;
import java.net.URL;

import org.apache.commons.io.FileUtils;
import org.grycap.gpf4med.DownloadService.DownloadConfiguration;
import org.grycap.gpf4med.conf.ConfigurationManager;
import org.grycap.gpf4med.exec.PostProcessTask;
import org.grycap.gpf4med.util.NamingUtils;
import org.grycap.gpf4med.util.URLUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.util.concurrent.SimpleTimeLimiter;

/**
 * Fetches documents from remote repositories. This class uses a cached thread pool, which over-performs 
 * for most cases. See {@link SimpleTimeLimiter} for a comprehensive explanation.
 * @author Erik Torres <ertorser@upv.es>
 *
 */
public enum DocumentFetcher {

    INSTANCE;

    private final static Logger LOGGER = LoggerFactory.getLogger(DocumentFetcher.class);

    public static final int CONNECTION_TIMEOUT_MILLIS = 60000; // 1 minutes
    public static final int READ_TIMEOUT_MILLIS = 180000; // 3 minutes
    public static final int RETRIES = 3;
    public static final double TIMEOUT_INCREMENT_PERCENTAGE = 0.5d;

    private DocumentFetcher() {
    }

    public void fecth(final ImmutableList<URL> urls) {
        checkArgument(urls != null, "Uninitialized URLs");
        final ImmutableMap.Builder<URI, File> pendingBuilder = new ImmutableMap.Builder<URI, File>();
        try {
            final File cacheDir = new File(ConfigurationManager.INSTANCE.getLocalCacheDir(), "reports");
            final ImmutableMap.Builder<URI, File> requestBuilder = new ImmutableMap.Builder<URI, File>();
            for (final URL url : urls) {
                try {
                    if (URLUtils.isRemoteProtocol(url)) {
                        final URI source = url.toURI().normalize();
                        final File destination = new File(cacheDir,
                                NamingUtils.genSafeFilename(new String[] { source.toString() }, null, ".xml"));
                        requestBuilder.put(source, destination);
                    } else if (URLUtils.isFileProtocol(url)) {
                        FileQueue.INSTANCE.add(FileUtils.toFile(url));
                    } else {
                        FileQueue.INSTANCE.failed(1);
                        LOGGER.warn("Ignoring unsupported URL: " + url.toString());
                    }
                } catch (Exception e2) {
                    FileQueue.INSTANCE.failed();
                }
            }
            final DownloadConfiguration downloadConfig = new DownloadConfiguration(CONNECTION_TIMEOUT_MILLIS,
                    READ_TIMEOUT_MILLIS, RETRIES, TIMEOUT_INCREMENT_PERCENTAGE);
            final ImmutableMap<URI, File> pending = new DownloadService().download(requestBuilder.build(), null,
                    downloadConfig, ConfigurationManager.INSTANCE.getFileEncryptionProvider(),
                    new PostProcessTask<File>() {
                        @Override
                        public void apply(final File object) {
                            FileQueue.INSTANCE.add(object);
                        }
                    });
            if (pending != null) {
                pendingBuilder.putAll(pending);
            }
        } catch (Exception e) {
            final ImmutableMap<URI, File> pending = pendingBuilder.build();
            if (pending != null && pending.size() > 0) {
                FileQueue.INSTANCE.failed(pending.size());
            }
        }
    }

}