marytts.tools.install.LicenseRegistry Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of marytts-runtime Show documentation
The newest version!
/**
 * Copyright 2009 DFKI GmbH.
 * All Rights Reserved.  Use is subject to license terms.
 *
 * This file is part of MARY TTS.
 *
 * MARY TTS 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, version 3 of the License.
 *
 * 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.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program.  If not, see .
 *
 */

package marytts.tools.install;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.HashMap;
import java.util.Map;
import java.util.StringTokenizer;

import org.apache.commons.io.IOUtils;

/**
 * A central book-keeping place for the licenses referenced by installable components. Licenses are identified by their URL and
 * kept in local files if they have been "used" before. A license gets "used" in particular when the user attempts to download a
 * component goverened by that license.
 * 
 * @author marc
 *
 */
public class LicenseRegistry {

	private static Map remote2local = null;

	/**
	 * For the license identified by the given URL, return the URL of a local file providing the same content as the given URL. If
	 * the license has not been downloaded yet, it will be now.
	 * 
	 * @param licenseURL
	 *            the remote URL of the license, serving as the license's identifier.
	 * @return the URL of a local file from which the license text can be read even if there is no internet connection.
	 */
	public static URL getLicense(URL licenseURL) {
		long startT = System.currentTimeMillis();
		if (remote2local == null) {
			loadLocalLicenses();
		}
		assert remote2local != null;
		if (!remote2local.containsKey(licenseURL)) {
			downloadLicense(licenseURL);
		}
		String localFilename = remote2local.get(licenseURL);
		File downloadDir = new File(System.getProperty("mary.downloadDir", "."));
		File localFile = new File(downloadDir, localFilename);
		try {
			URL localURL = localFile.toURI().toURL();
			System.out.println("Lookup took " + (System.currentTimeMillis() - startT) + " ms");
			return localURL;
		} catch (MalformedURLException e) {
			System.err.println("Cannot create URL from local file " + localFile.getAbsolutePath());
			e.printStackTrace();
		}
		return null;
	}

	private static void loadLocalLicenses() {
		remote2local = new HashMap();
		File downloadDir = new File(System.getProperty("mary.downloadDir", "."));
		File licenseIndexFile = new File(downloadDir, "license-index.txt");
		if (!licenseIndexFile.canRead()) {
			return; // nothing to load
		}
		try (BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream(licenseIndexFile), "UTF-8"))) {
			// Each line in licenseIndexFile is expected to be a pair of local file name (relative to downloadDir) and URL string,
			// separated by a | (pipe) character.

			String line;
			while ((line = br.readLine()) != null) {
				line = line.trim();
				StringTokenizer st = new StringTokenizer(line, "|");
				if (!st.hasMoreTokens()) {
					continue; // skip empty lines
				}
				String localFilename = st.nextToken().trim();
				if (!st.hasMoreTokens()) {
					continue; // skip lines that don't contain a |
				}
				String remoteURLString = st.nextToken().trim();
				File localLicenseFile = new File(downloadDir, localFilename);
				if (!localLicenseFile.canRead()) {
					System.err.println("License index file " + licenseIndexFile.getAbsolutePath() + " refers to license file "
							+ localLicenseFile.getAbsolutePath() + ", but that file cannot be read. Skipping.");
					continue;
				}
				URL remoteURL = new URL(remoteURLString);
				remote2local.put(remoteURL, localFilename);
			}
		} catch (IOException e) {
			System.err.println("Problem reading local license index file " + licenseIndexFile.getAbsolutePath() + ":");
			e.printStackTrace();
		}
	}

	private static void downloadLicense(URL licenseURL) {

		assert remote2local != null;
		File downloadDir = new File(System.getProperty("mary.downloadDir", "."));
		String filename = licenseURL.toString().replace('/', '_').replace(':', '_');
		File licenseFile = new File(downloadDir, filename);
		System.out.println("Downloading license from " + licenseURL.toString());
		try (FileOutputStream out = new FileOutputStream(licenseFile); InputStream in = licenseURL.openStream()) {
			IOUtils.copy(in, out);
		} catch (IOException e) {
			System.err.println("Cannot download license from " + licenseURL.toString());
			e.printStackTrace();
		}

		// Now we need to update remote2local and write an updated license-index.txt:
		remote2local.put(licenseURL, filename);
		saveIndex();

	}

	private static void saveIndex() {
		assert remote2local != null;
		File downloadDir = new File(System.getProperty("mary.downloadDir", "."));
		File licenseIndexFile = new File(downloadDir, "license-index.txt");
		try (PrintWriter pw = new PrintWriter(new OutputStreamWriter(new FileOutputStream(licenseIndexFile), "UTF-8"))) {
			for (URL remote : remote2local.keySet()) {
				pw.println(remote2local.get(remote) + "|" + remote.toString());
			}
		} catch (IOException e) {
			System.err.println("Problem updating the index file " + licenseIndexFile.getAbsolutePath());
			e.printStackTrace();
		}

	}

}