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/*
* This file is part of the Heritrix web crawler (crawler.archive.org).
*
* Licensed to the Internet Archive (IA) by one or more individual
* contributors.
*
* The IA 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.archive.io;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;
import org.archive.io.arc.ARCReaderFactory;
import org.archive.io.warc.WARCReaderFactory;
import org.archive.net.md5.Md5URLConnection;
import org.archive.net.rsync.RsyncURLConnection;
import org.archive.url.UsableURI;
import org.archive.util.FileUtils;
/**
* Factory that returns an Archive file Reader.
* Returns Readers for ARCs or WARCs.
* @author stack
* @version $Date$ $Revision$
*/
public class ArchiveReaderFactory implements ArchiveFileConstants {
// Static block to enable S3 URLs
static {
if (System.getProperty("java.protocol.handler.pkgs") != null) {
System.setProperty("java.protocol.handler.pkgs",
System.getProperty("java.protocol.handler.pkgs")
+ "|" + "org.archive.net");
} else {
System.setProperty("java.protocol.handler.pkgs", "org.archive.net");
}
}
private static final ArchiveReaderFactory factory =
new ArchiveReaderFactory();
/**
* Shutdown any public access to default constructor.
*/
protected ArchiveReaderFactory() {
super();
}
/**
* Get an Archive file Reader on passed path or url.
* Does primitive heuristic figuring if path or URL.
* @param arcFileOrUrl File path or URL pointing at an Archive file.
* @return An Archive file Reader.
* @throws IOException
* @throws MalformedURLException
* @throws IOException
*/
public static ArchiveReader get(final String arcFileOrUrl)
throws MalformedURLException, IOException {
return ArchiveReaderFactory.factory.getArchiveReader(arcFileOrUrl);
}
protected ArchiveReader getArchiveReader(final String arcFileOrUrl)
throws MalformedURLException, IOException {
return getArchiveReader(arcFileOrUrl, 0);
}
protected ArchiveReader getArchiveReader(final String arcFileOrUrl,
final long offset)
throws MalformedURLException, IOException {
return UsableURI.hasScheme(arcFileOrUrl) && arcFileOrUrl.indexOf(":")>1?
get(new URL(arcFileOrUrl), offset):
get(new File(arcFileOrUrl), offset);
}
/**
* @param f An Archive file to read.
* @return An ArchiveReader
* @throws IOException
*/
public static ArchiveReader get(final File f) throws IOException {
return ArchiveReaderFactory.factory.getArchiveReader(f);
}
protected ArchiveReader getArchiveReader(final File f)
throws IOException {
return getArchiveReader(f, 0);
}
/**
* @param f An Archive file to read.
* @param offset Have returned Reader set to start reading at this offset.
* @return An ArchiveReader
* @throws IOException
*/
public static ArchiveReader get(final File f, final long offset)
throws IOException {
return ArchiveReaderFactory.factory.getArchiveReader(f, offset);
}
protected ArchiveReader getArchiveReader(final File f,
final long offset)
throws IOException {
if (ARCReaderFactory.isARCSuffix(f.getName())) {
return ARCReaderFactory.get(f, true, offset);
} else if (WARCReaderFactory.isWARCSuffix(f.getName())) {
return WARCReaderFactory.get(f, offset);
}
throw new IOException("Unknown file extension (Not ARC nor WARC): "
+ f.getName());
}
/**
* Wrap a Reader around passed Stream.
* @param s Identifying String for this Stream used in error messages.
* Must be a string that ends with the name of the file we're to put
* an ArchiveReader on. This code looks at file endings to figure
* whether to return an ARC or WARC reader.
* @param is Stream. Stream will be wrapped with implementation of
* RepositionableStream unless already supported.
* @param atFirstRecord Are we at first Record?
* @return ArchiveReader.
* @throws IOException
*/
public static ArchiveReader get(final String s, final InputStream is,
final boolean atFirstRecord)
throws IOException {
return ArchiveReaderFactory.factory.getArchiveReader(s, is,
atFirstRecord);
}
protected ArchiveReader getArchiveReader(final String id,
final InputStream is, final boolean atFirstRecord)
throws IOException {
final InputStream stream = is;
if (ARCReaderFactory.isARCSuffix(id)) {
return ARCReaderFactory.get(id, stream, atFirstRecord);
} else if (WARCReaderFactory.isWARCSuffix(id)) {
return WARCReaderFactory.get(id, stream, atFirstRecord);
}
throw new IOException("Unknown extension (Not ARC nor WARC): " + id);
}
/**
* Get an Archive Reader aligned at offset.
* This version of get will not bring the file local but will try to
* stream across the net making an HTTP 1.1 Range request on remote
* http server (RFC1435 Section 14.35).
* @param u HTTP URL for an Archive file.
* @param offset Offset into file at which to start fetching.
* @return An ArchiveReader aligned at offset.
* @throws IOException
*/
public static ArchiveReader get(final URL u, final long offset)
throws IOException {
return ArchiveReaderFactory.factory.getArchiveReader(u, offset);
}
protected ArchiveReader getArchiveReader(final URL f, final long offset)
throws IOException {
// Get URL connection.
URLConnection connection = f.openConnection();
if (connection instanceof HttpURLConnection) {
addUserAgent((HttpURLConnection)connection);
}
if (offset != 0) {
// Use a Range request (Assumes HTTP 1.1 on other end). If
// length >= 0, add open-ended range header to the request. Else,
// because end-byte is inclusive, subtract 1.
connection.addRequestProperty("Range", "bytes=" + offset + "-");
// TODO: should actually verify that server respected 'Range' request
// (spec allows them to ignore; 206 response or Content-Range header
// should be present if Range satisfied; multipart/byteranges could be
// a problem).
}
return getArchiveReader(f.toString(), connection.getInputStream(), (offset == 0));
}
/**
* Get an ARCReader.
* Pulls the ARC local into whereever the System Property
* java.io.tmpdir points. It then hands back an ARCReader that
* points at this local copy. A close on this ARCReader instance will
* remove the local copy.
* @param u An URL that points at an ARC.
* @return An ARCReader.
* @throws IOException
*/
public static ArchiveReader get(final URL u)
throws IOException {
return ArchiveReaderFactory.factory.getArchiveReader(u);
}
protected ArchiveReader getArchiveReader(final URL u)
throws IOException {
// If url represents a local file then return file it points to.
if (u.getPath() != null) {
// TODO: Add scheme check and host check.
File f = new File(u.getPath());
if (f.exists()) {
return get(f, 0);
}
}
String scheme = u.getProtocol();
if (scheme.startsWith("http") || scheme.equals("s3")) {
// Try streaming if http or s3 URLs rather than copying local
// and then reading (Passing an offset will get us an Reader
// that wraps a Stream).
return get(u, 0);
}
return makeARCLocal(u.openConnection());
}
protected ArchiveReader makeARCLocal(final URLConnection connection)
throws IOException {
File localFile = null;
if (connection instanceof HttpURLConnection) {
// If http url connection, bring down the resource local.
String p = connection.getURL().getPath();
int index = p.lastIndexOf('/');
if (index >= 0) {
// Name file for the file we're making local.
localFile = File.createTempFile("",p.substring(index + 1));
if (localFile.exists()) {
// If file of same name already exists in TMPDIR, then
// clean it up (Assuming only reason a file of same name in
// TMPDIR is because we failed a previous download).
localFile.delete();
}
} else {
localFile = File.createTempFile(ArchiveReader.class.getName(),
".tmp");
}
addUserAgent((HttpURLConnection)connection);
connection.connect();
try {
FileUtils.readFullyToFile(connection.getInputStream(), localFile);
} catch (IOException ioe) {
localFile.delete();
throw ioe;
}
} else if (connection instanceof RsyncURLConnection) {
// Then, connect and this will create a local file.
// See implementation of the rsync handler.
connection.connect();
localFile = ((RsyncURLConnection)connection).getFile();
} else if (connection instanceof Md5URLConnection) {
// Then, connect and this will create a local file.
// See implementation of the md5 handler.
connection.connect();
localFile = ((Md5URLConnection)connection).getFile();
} else {
throw new UnsupportedOperationException("No support for " +
connection);
}
ArchiveReader reader = null;
try {
reader = get(localFile, 0);
} catch (IOException e) {
localFile.delete();
throw e;
}
// Return a delegate that does cleanup of downloaded file on close.
return reader.getDeleteFileOnCloseReader(localFile);
}
protected void addUserAgent(final HttpURLConnection connection) {
connection.addRequestProperty("User-Agent", this.getClass().getName());
}
/**
* @param f File to test.
* @return True if f is compressed.
* @throws IOException
*/
protected boolean isCompressed(final File f) throws IOException {
return f.getName().toLowerCase().
endsWith(DOT_COMPRESSED_FILE_EXTENSION);
}
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