/*
* 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.tools.ant.taskdefs;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLConnection;
import java.util.Date;
import org.apache.tools.ant.BuildException;
import org.apache.tools.ant.Project;
import org.apache.tools.ant.Task;
import org.apache.tools.ant.types.Mapper;
import org.apache.tools.ant.types.Resource;
import org.apache.tools.ant.types.ResourceCollection;
import org.apache.tools.ant.types.resources.Resources;
import org.apache.tools.ant.types.resources.URLProvider;
import org.apache.tools.ant.types.resources.URLResource;
import org.apache.tools.ant.util.FileNameMapper;
import org.apache.tools.ant.util.FileUtils;
/**
* Gets a particular file from a URL source.
* Options include verbose reporting, timestamp based fetches and controlling
* actions on failures. NB: access through a firewall only works if the whole
* Java runtime is correctly configured.
*
* @since Ant 1.1
*
* @ant.task category="network"
*/
public class Get extends Task {
private static final int NUMBER_RETRIES = 3;
private static final int DOTS_PER_LINE = 50;
private static final int BIG_BUFFER_SIZE = 100 * 1024;
private static final FileUtils FILE_UTILS = FileUtils.getFileUtils();
private static final int REDIRECT_LIMIT = 25;
// HttpURLConnection doesn't have a constant for this in Java5 and
// what it calls HTTP_MOVED_TEMP would better be FOUND
private static final int HTTP_MOVED_TEMP = 307;
private static final String HTTP = "http";
private static final String HTTPS = "https";
private Resources sources = new Resources();
private File destination; // required
private boolean verbose = false;
private boolean useTimestamp = false; //off by default
private boolean ignoreErrors = false;
private String uname = null;
private String pword = null;
private long maxTime = 0;
private int numberRetries = NUMBER_RETRIES;
private boolean skipExisting = false;
private boolean httpUseCaches = true; // on by default
private Mapper mapperElement = null;
/**
* Does the work.
*
* @exception BuildException Thrown in unrecoverable error.
*/
public void execute() throws BuildException {
checkAttributes();
for (Resource r : sources) {
URLProvider up = r.as(URLProvider.class);
URL source = up.getURL();
File dest = destination;
if (destination.isDirectory()) {
if (mapperElement == null) {
String path = source.getPath();
if (path.endsWith("/")) {
path = path.substring(0, path.length() - 1);
}
int slash = path.lastIndexOf("/");
if (slash > -1) {
path = path.substring(slash + 1);
}
dest = new File(destination, path);
} else {
FileNameMapper mapper = mapperElement.getImplementation();
String[] d = mapper.mapFileName(source.toString());
if (d == null) {
log("skipping " + r + " - mapper can't handle it",
Project.MSG_WARN);
continue;
} else if (d.length == 0) {
log("skipping " + r + " - mapper returns no file name",
Project.MSG_WARN);
continue;
} else if (d.length > 1) {
log("skipping " + r + " - mapper returns multiple file"
+ " names", Project.MSG_WARN);
continue;
}
dest = new File(destination, d[0]);
}
}
//set up logging
int logLevel = Project.MSG_INFO;
DownloadProgress progress = null;
if (verbose) {
progress = new VerboseProgress(System.out);
}
//execute the get
try {
doGet(source, dest, logLevel, progress);
} catch (IOException ioe) {
log("Error getting " + source + " to " + dest);
if (!ignoreErrors) {
throw new BuildException(ioe, getLocation());
}
}
}
}
/**
* make a get request, with the supplied progress and logging info.
* All the other config parameters are set at the task level,
* source, dest, ignoreErrors, etc.
* @param logLevel level to log at, see {@link Project#log(String, int)}
* @param progress progress callback; null for no-callbacks
* @return true for a successful download, false otherwise.
* The return value is only relevant when {@link #ignoreErrors} is true, as
* when false all failures raise BuildExceptions.
* @throws IOException for network trouble
* @throws BuildException for argument errors, or other trouble when ignoreErrors
* is false.
* @deprecated only gets the first configured resource
*/
public boolean doGet(int logLevel, DownloadProgress progress)
throws IOException {
checkAttributes();
for (Resource r : sources) {
URLProvider up = r.as(URLProvider.class);
URL source = up.getURL();
return doGet(source, destination, logLevel, progress);
}
/*NOTREACHED*/
return false;
}
/**
* make a get request, with the supplied progress and logging info.
*
* All the other config parameters like ignoreErrors are set at
* the task level.
* @param source the URL to get
* @param dest the target file
* @param logLevel level to log at, see {@link Project#log(String, int)}
* @param progress progress callback; null for no-callbacks
* @return true for a successful download, false otherwise.
* The return value is only relevant when {@link #ignoreErrors} is true, as
* when false all failures raise BuildExceptions.
* @throws IOException for network trouble
* @throws BuildException for argument errors, or other trouble when ignoreErrors
* is false.
* @since Ant 1.8.0
*/
public boolean doGet(URL source, File dest, int logLevel,
DownloadProgress progress)
throws IOException {
if (dest.exists() && skipExisting) {
log("Destination already exists (skipping): "
+ dest.getAbsolutePath(), logLevel);
return true;
}
//dont do any progress, unless asked
if (progress == null) {
progress = new NullProgress();
}
log("Getting: " + source, logLevel);
log("To: " + dest.getAbsolutePath(), logLevel);
//set the timestamp to the file date.
long timestamp = 0;
boolean hasTimestamp = false;
if (useTimestamp && dest.exists()) {
timestamp = dest.lastModified();
if (verbose) {
Date t = new Date(timestamp);
log("local file date : " + t.toString(), logLevel);
}
hasTimestamp = true;
}
GetThread getThread = new GetThread(source, dest,
hasTimestamp, timestamp, progress,
logLevel);
getThread.setDaemon(true);
getProject().registerThreadTask(getThread, this);
getThread.start();
try {
getThread.join(maxTime * 1000);
} catch (InterruptedException ie) {
log("interrupted waiting for GET to finish",
Project.MSG_VERBOSE);
}
if (getThread.isAlive()) {
String msg = "The GET operation took longer than " + maxTime
+ " seconds, stopping it.";
if (ignoreErrors) {
log(msg);
}
getThread.closeStreams();
if (!ignoreErrors) {
throw new BuildException(msg);
}
return false;
}
return getThread.wasSuccessful();
}
/**
* Check the attributes.
*/
private void checkAttributes() {
if (sources.size() == 0) {
throw new BuildException("at least one source is required",
getLocation());
}
for (Resource r : sources) {
URLProvider up = r.as(URLProvider.class);
if (up == null) {
throw new BuildException("Only URLProvider resources are"
+ " supported", getLocation());
}
}
if (destination == null) {
throw new BuildException("dest attribute is required", getLocation());
}
if (destination.exists() && sources.size() > 1
&& !destination.isDirectory()) {
throw new BuildException("The specified destination is not a"
+ " directory",
getLocation());
}
if (destination.exists() && !destination.canWrite()) {
throw new BuildException("Can't write to "
+ destination.getAbsolutePath(),
getLocation());
}
if (sources.size() > 1 && !destination.exists()) {
destination.mkdirs();
}
}
/**
* Set an URL to get.
*
* @param u URL for the file.
*/
public void setSrc(URL u) {
add(new URLResource(u));
}
/**
* Adds URLs to get.
* @since Ant 1.8.0
*/
public void add(ResourceCollection rc) {
sources.add(rc);
}
/**
* Where to copy the source file.
*
* @param dest Path to file.
*/
public void setDest(File dest) {
this.destination = dest;
}
/**
* If true, show verbose progress information.
*
* @param v if "true" then be verbose
*/
public void setVerbose(boolean v) {
verbose = v;
}
/**
* If true, log errors but do not treat as fatal.
*
* @param v if "true" then don't report download errors up to ant
*/
public void setIgnoreErrors(boolean v) {
ignoreErrors = v;
}
/**
* If true, conditionally download a file based on the timestamp
* of the local copy.
*
* <p>In this situation, the if-modified-since header is set so
* that the file is only fetched if it is newer than the local
* file (or there is no local file) This flag is only valid on
* HTTP connections, it is ignored in other cases. When the flag
* is set, the local copy of the downloaded file will also have
* its timestamp set to the remote file time.</p>
*
* <p>Note that remote files of date 1/1/1970 (GMT) are treated as
* 'no timestamp', and web servers often serve files with a
* timestamp in the future by replacing their timestamp with that
* of the current time. Also, inter-computer clock differences can
* cause no end of grief.</p>
* @param v "true" to enable file time fetching
*/
public void setUseTimestamp(boolean v) {
useTimestamp = v;
}
/**
* Username for basic auth.
*
* @param u username for authentication
*/
public void setUsername(String u) {
this.uname = u;
}
/**
* password for the basic authentication.
*
* @param p password for authentication
*/
public void setPassword(String p) {
this.pword = p;
}
/**
* The time in seconds the download is allowed to take before
* being terminated.
*
* @since Ant 1.8.0
*/
public void setMaxTime(long maxTime) {
this.maxTime = maxTime;
}
/**
* The number of retries to attempt upon error, defaults to 3.
*
* @param r retry count
*
* @since Ant 1.8.0
*/
public void setRetries(int r) {
this.numberRetries = r;
}
/**
* Skip files that already exist locally.
*
* @param s "true" to skip existing destination files
*
* @since Ant 1.8.0
*/
public void setSkipExisting(boolean s) {
this.skipExisting = s;
}
/**
* HTTP connections only - control caching on the
* HttpUrlConnection: httpConnection.setUseCaches(); if false, do
* not allow caching on the HttpUrlConnection.
*
* <p>Defaults to true (allow caching, which is also the
* HttpUrlConnection default value.</p>
*
* @since Ant 1.8.0
*/
public void setHttpUseCaches(boolean httpUseCache) {
this.httpUseCaches = httpUseCache;
}
/**
* Define the mapper to map source to destination files.
* @return a mapper to be configured.
* @exception BuildException if more than one mapper is defined.
* @since Ant 1.8.0
*/
public Mapper createMapper() throws BuildException {
if (mapperElement != null) {
throw new BuildException("Cannot define more than one mapper",
getLocation());
}
mapperElement = new Mapper(getProject());
return mapperElement;
}
/**
* Add a nested filenamemapper.
* @param fileNameMapper the mapper to add.
* @since Ant 1.8.0
*/
public void add(FileNameMapper fileNameMapper) {
createMapper().add(fileNameMapper);
}
/**
* Provide this for Backward Compatibility.
*/
protected static class Base64Converter
extends org.apache.tools.ant.util.Base64Converter {
}
/**
* Interface implemented for reporting
* progress of downloading.
*/
public interface DownloadProgress {
/**
* begin a download
*/
void beginDownload();
/**
* tick handler
*
*/
void onTick();
/**
* end a download
*/
void endDownload();
}
/**
* do nothing with progress info
*/
public static class NullProgress implements DownloadProgress {
/**
* begin a download
*/
public void beginDownload() {
}
/**
* tick handler
*
*/
public void onTick() {
}
/**
* end a download
*/
public void endDownload() {
}
}
/**
* verbose progress system prints to some output stream
*/
public static class VerboseProgress implements DownloadProgress {
private int dots = 0;
// CheckStyle:VisibilityModifier OFF - bc
PrintStream out;
// CheckStyle:VisibilityModifier ON
/**
* Construct a verbose progress reporter.
* @param out the output stream.
*/
public VerboseProgress(PrintStream out) {
this.out = out;
}
/**
* begin a download
*/
public void beginDownload() {
dots = 0;
}
/**
* tick handler
*
*/
public void onTick() {
out.print(".");
if (dots++ > DOTS_PER_LINE) {
out.flush();
dots = 0;
}
}
/**
* end a download
*/
public void endDownload() {
out.println();
out.flush();
}
}
private class GetThread extends Thread {
private final URL source;
private final File dest;
private final boolean hasTimestamp;
private final long timestamp;
private final DownloadProgress progress;
private final int logLevel;
private boolean success = false;
private IOException ioexception = null;
private BuildException exception = null;
private InputStream is = null;
private OutputStream os = null;
private URLConnection connection;
private int redirections = 0;
GetThread(URL source, File dest,
boolean h, long t, DownloadProgress p, int l) {
this.source = source;
this.dest = dest;
hasTimestamp = h;
timestamp = t;
progress = p;
logLevel = l;
}
public void run() {
try {
success = get();
} catch (IOException ioex) {
ioexception = ioex;
} catch (BuildException bex) {
exception = bex;
}
}
private boolean get() throws IOException, BuildException {
connection = openConnection(source);
if (connection == null)
{
return false;
}
boolean downloadSucceeded = downloadFile();
//if (and only if) the use file time option is set, then
//the saved file now has its timestamp set to that of the
//downloaded file
if (downloadSucceeded && useTimestamp) {
updateTimeStamp();
}
return downloadSucceeded;
}
private boolean redirectionAllowed(URL aSource, URL aDest) {
if (!(aSource.getProtocol().equals(aDest.getProtocol()) || (HTTP
.equals(aSource.getProtocol()) && HTTPS.equals(aDest
.getProtocol())))) {
String message = "Redirection detected from "
+ aSource.getProtocol() + " to " + aDest.getProtocol()
+ ". Protocol switch unsafe, not allowed.";
if (ignoreErrors) {
log(message, logLevel);
return false;
} else {
throw new BuildException(message);
}
}
redirections++;
if (redirections > REDIRECT_LIMIT) {
String message = "More than " + REDIRECT_LIMIT
+ " times redirected, giving up";
if (ignoreErrors) {
log(message, logLevel);
return false;
} else {
throw new BuildException(message);
}
}
return true;
}
private URLConnection openConnection(URL aSource) throws IOException {
// set up the URL connection
URLConnection connection = aSource.openConnection();
// modify the headers
// NB: things like user authentication could go in here too.
if (hasTimestamp) {
connection.setIfModifiedSince(timestamp);
}
// prepare Java 1.1 style credentials
if (uname != null || pword != null) {
String up = uname + ":" + pword;
String encoding;
// we do not use the sun impl for portability,
// and always use our own implementation for consistent
// testing
Base64Converter encoder = new Base64Converter();
encoding = encoder.encode(up.getBytes());
connection.setRequestProperty("Authorization", "Basic "
+ encoding);
}
if (connection instanceof HttpURLConnection) {
((HttpURLConnection) connection)
.setInstanceFollowRedirects(false);
((HttpURLConnection) connection)
.setUseCaches(httpUseCaches);
}
// connect to the remote site (may take some time)
try {
connection.connect();
} catch (NullPointerException e) {
//bad URLs can trigger NPEs in some JVMs
throw new BuildException("Failed to parse " + source.toString(), e);
}
// First check on a 301 / 302 (moved) response (HTTP only)
if (connection instanceof HttpURLConnection) {
HttpURLConnection httpConnection = (HttpURLConnection) connection;
int responseCode = httpConnection.getResponseCode();
if (responseCode == HttpURLConnection.HTTP_MOVED_PERM ||
responseCode == HttpURLConnection.HTTP_MOVED_TEMP ||
responseCode == HttpURLConnection.HTTP_SEE_OTHER ||
responseCode == HTTP_MOVED_TEMP)
{
String newLocation = httpConnection.getHeaderField("Location");
String message = aSource
+ (responseCode == HttpURLConnection.HTTP_MOVED_PERM ? " permanently"
: "") + " moved to " + newLocation;
log(message, logLevel);
URL newURL = new URL(aSource, newLocation);
if (!redirectionAllowed(aSource, newURL))
{
return null;
}
return openConnection(newURL);
}
// next test for a 304 result (HTTP only)
long lastModified = httpConnection.getLastModified();
if (responseCode == HttpURLConnection.HTTP_NOT_MODIFIED
|| (lastModified != 0 && hasTimestamp && timestamp >= lastModified)) {
// not modified so no file download. just return
// instead and trace out something so the user
// doesn't think that the download happened when it
// didn't
log("Not modified - so not downloaded", logLevel);
return null;
}
// test for 401 result (HTTP only)
if (responseCode == HttpURLConnection.HTTP_UNAUTHORIZED) {
String message = "HTTP Authorization failure";
if (ignoreErrors) {
log(message, logLevel);
return null;
} else {
throw new BuildException(message);
}
}
}
//REVISIT: at this point even non HTTP connections may
//support the if-modified-since behaviour -we just check
//the date of the content and skip the write if it is not
//newer. Some protocols (FTP) don't include dates, of
//course.
return connection;
}
private boolean downloadFile()
throws FileNotFoundException, IOException {
for (int i = 0; i < numberRetries; i++) {
// this three attempt trick is to get round quirks in different
// Java implementations. Some of them take a few goes to bind
// property; we ignore the first couple of such failures.
try {
is = connection.getInputStream();
break;
} catch (IOException ex) {
log("Error opening connection " + ex, logLevel);
}
}
if (is == null) {
log("Can't get " + source + " to " + dest, logLevel);
if (ignoreErrors) {
return false;
}
throw new BuildException("Can't get " + source + " to " + dest,
getLocation());
}
os = new FileOutputStream(dest);
progress.beginDownload();
boolean finished = false;
try {
byte[] buffer = new byte[BIG_BUFFER_SIZE];
int length;
while (!isInterrupted() && (length = is.read(buffer)) >= 0) {
os.write(buffer, 0, length);
progress.onTick();
}
finished = !isInterrupted();
} finally {
FileUtils.close(os);
FileUtils.close(is);
// we have started to (over)write dest, but failed.
// Try to delete the garbage we'd otherwise leave
// behind.
if (!finished) {
dest.delete();
}
}
progress.endDownload();
return true;
}
private void updateTimeStamp() {
long remoteTimestamp = connection.getLastModified();
if (verbose) {
Date t = new Date(remoteTimestamp);
log("last modified = " + t.toString()
+ ((remoteTimestamp == 0)
? " - using current time instead"
: ""), logLevel);
}
if (remoteTimestamp != 0) {
FILE_UTILS.setFileLastModified(dest, remoteTimestamp);
}
}
/**
* Has the download completed successfully?
*
* <p>Re-throws any exception caught during executaion.</p>
*/
boolean wasSuccessful() throws IOException, BuildException {
if (ioexception != null) {
throw ioexception;
}
if (exception != null) {
throw exception;
}
return success;
}
/**
* Closes streams, interrupts the download, may delete the
* output file.
*/
void closeStreams() {
interrupt();
FileUtils.close(os);
FileUtils.close(is);
if (!success && dest.exists()) {
dest.delete();
}
}
}
}