WebDownloadUtils.java

/*******************************************************************************
 * Copyright (c) 2009, 2010 SpringSource, a divison of VMware, Inc.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     SpringSource, a division of VMware, Inc. - initial API and implementation
 *******************************************************************************/
package org.eclipse.virgo.ide.runtime.internal.core.utils;

import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.util.Date;

import org.apache.commons.httpclient.Credentials;
import org.apache.commons.httpclient.Header;
import org.apache.commons.httpclient.HostConfiguration;
import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.NTCredentials;
import org.apache.commons.httpclient.UsernamePasswordCredentials;
import org.apache.commons.httpclient.auth.AuthScope;
import org.apache.commons.httpclient.methods.GetMethod;
import org.apache.commons.httpclient.util.DateUtil;
import org.eclipse.core.net.proxy.IProxyData;
import org.eclipse.core.net.proxy.IProxyService;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.Status;
import org.eclipse.virgo.ide.runtime.core.ServerCorePlugin;
import org.osgi.framework.ServiceReference;


/**
 * Utility to download files using Apache HTTPClient with using Eclipse's proxy service.
 * @author Christian Dupuis
 * @since 1.0.0
 */
public class WebDownloadUtils {

	private static final int CONNNECT_TIMEOUT = 60000;

	private static final int HTTP_PORT = 80;

	private static final int SOCKET_TIMEOUT = 60000;

	private static Credentials getCredentials(IProxyData proxyData, String host) {
		int i = proxyData.getUserId().indexOf("\\");
		if (i > 0 && i < proxyData.getUserId().length() - 1) {
			return new NTCredentials(proxyData.getUserId().substring(i + 1), proxyData.getPassword(), host, proxyData
					.getUserId().substring(0, i));
		}
		else {
			return new UsernamePasswordCredentials(proxyData.getUserId(), proxyData.getPassword());
		}
	}

	private static String getHost(String repositoryUrl) {
		String result = repositoryUrl;
		int colonSlashSlash = repositoryUrl.indexOf("://");

		if (colonSlashSlash >= 0) {
			result = repositoryUrl.substring(colonSlashSlash + 3);
		}

		int colonPort = result.indexOf(':');
		int requestPath = result.indexOf('/');

		int substringEnd;

		// minimum positive, or string length
		if (colonPort > 0 && requestPath > 0) {
			substringEnd = Math.min(colonPort, requestPath);
		}
		else if (colonPort > 0) {
			substringEnd = colonPort;
		}
		else if (requestPath > 0) {
			substringEnd = requestPath;
		}
		else {
			substringEnd = result.length();
		}

		return result.substring(0, substringEnd);
	}

	public static Date getLastModifiedDate(String url, IProgressMonitor monitor) {
		GetMethod method = null;
		BufferedInputStream bis = null;
		FileOutputStream fos = null;
		try {
			if (monitor.isCanceled()) {
				return null;
			}
			HttpClient client = new HttpClient();
			method = new GetMethod(url);
			method.setFollowRedirects(true);

			HostConfiguration hostConfiguration = new HostConfiguration();
			hostConfiguration.setHost(getHost(url), HTTP_PORT, "http");

			configureHttpClientProxy(url, client, hostConfiguration);

			client.getHttpConnectionManager().getParams().setSoTimeout(SOCKET_TIMEOUT);
			client.getHttpConnectionManager().getParams().setConnectionTimeout(CONNNECT_TIMEOUT);

			// Execute the GET method
			int statusCode = client.executeMethod(hostConfiguration, method);
			if (statusCode == 200) {

				if (monitor.isCanceled()) {
					return null;
				}

				Header lastModified = method.getResponseHeader("Last-Modified");
				if (lastModified != null) {
					return DateUtil.parseDate(lastModified.getValue());
				}
			}
		}
		catch (Exception e) {
		}
		finally {
			try {
				if (method != null) {
					method.releaseConnection();
				}
			}
			catch (Exception e2) {
			}
			try {
				if (bis != null) {
					bis.close();
				}
			}
			catch (Exception e2) {
			}
			try {
				if (fos != null) {
					fos.close();
				}
			}
			catch (Exception e2) {
			}
		}
		return null;
	}

	public static File downloadFile(String url, File outputPath, IProgressMonitor monitor) {
		GetMethod method = null;
		BufferedInputStream bis = null;
		FileOutputStream fos = null;
		File outputFile = null;
		try {
			if (monitor.isCanceled()) {
				return null;
			}
			HttpClient client = new HttpClient();
			method = new GetMethod(url);
			method.setFollowRedirects(true);

			HostConfiguration hostConfiguration = new HostConfiguration();
			hostConfiguration.setHost(getHost(url), HTTP_PORT, "http");

			configureHttpClientProxy(url, client, hostConfiguration);

			client.getHttpConnectionManager().getParams().setSoTimeout(SOCKET_TIMEOUT);
			client.getHttpConnectionManager().getParams().setConnectionTimeout(CONNNECT_TIMEOUT);

			// Execute the GET method
			int statusCode = client.executeMethod(hostConfiguration, method);
			if (statusCode == 200) {

				int ix = method.getPath().lastIndexOf('/');
				String fileName = method.getPath().substring(ix + 1);
				monitor.subTask("Downloading file '" + fileName + "'");

				if (monitor.isCanceled()) {
					return null;
				}

				Header[] header = method.getResponseHeaders("content-length");
				long totalBytes = Long.valueOf(header[0].getValue());

				InputStream is = method.getResponseBodyAsStream();
				bis = new BufferedInputStream(is);
				outputFile = new File(outputPath, fileName);
				fos = new FileOutputStream(outputFile);
				long bytesRead = 0;
				byte[] bytes = new byte[8192];
				int count = bis.read(bytes);
				while (count != -1 && count <= 8192) {
					if (monitor.isCanceled()) {
						return null;
					}
					bytesRead = bytesRead + count;
					float percent = (Float.valueOf(bytesRead) / Float.valueOf(totalBytes)) * 100;
					monitor.subTask("Downloading file '" + fileName + "': " + bytesRead + "bytes/" + totalBytes
							+ "bytes (" + Math.round(percent) + "%)");
					fos.write(bytes, 0, count);
					count = bis.read(bytes);
				}
				if (count != -1) {
					fos.write(bytes, 0, count);
				}
			}

			return outputFile;
		}
		catch (Exception e) {
			ServerCorePlugin.getDefault().getLog().log(
					new Status(Status.ERROR, ServerCorePlugin.PLUGIN_ID, 1, "Error downloading bundle/library", e));
		}
		finally {
			try {
				if (method != null) {
					method.releaseConnection();
				}
			}
			catch (Exception e2) {
			}
			try {
				if (bis != null) {
					bis.close();
				}
			}
			catch (Exception e2) {
			}
			try {
				if (fos != null) {
					fos.close();
				}
			}
			catch (Exception e2) {
			}
		}

		return null;
	}

	private static void configureHttpClientProxy(String url, HttpClient client, HostConfiguration hostConfiguration) {
		ServiceReference services = ServerCorePlugin.getDefault().getBundle().getBundleContext().getServiceReference(
				IProxyService.class.getName());
		if (services != null) {
			IProxyService proxyService = (IProxyService) ServerCorePlugin.getDefault().getBundle().getBundleContext()
					.getService(services);
			IProxyData proxyData = proxyService.getProxyDataForHost(getHost(url), IProxyData.HTTP_PROXY_TYPE);
			if (proxyService.isProxiesEnabled() && proxyData != null) {
				hostConfiguration.setProxy(proxyData.getHost(), proxyData.getPort());
			}
			if (proxyData != null && proxyData.isRequiresAuthentication()) {
				client.getState().setProxyCredentials(AuthScope.ANY, getCredentials(proxyData, getHost(url)));
			}
		}
	}

}