/**
* 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.hadoop.hdfs;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.net.ConnectException;
import java.net.HttpURLConnection;
import java.net.InetSocketAddress;
import java.net.URI;
import java.net.URISyntaxException;
import java.net.URL;
import java.security.PrivilegedExceptionAction;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Collection;
import java.util.TimeZone;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.ContentSummary;
import org.apache.hadoop.fs.DelegationTokenRenewer;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FSDataOutputStream;
import org.apache.hadoop.fs.FileChecksum;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.MD5MD5CRC32FileChecksum;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.fs.permission.FsPermission;
import org.apache.hadoop.hdfs.security.token.delegation.DelegationTokenIdentifier;
import org.apache.hadoop.hdfs.security.token.delegation.DelegationTokenSelector;
import org.apache.hadoop.hdfs.server.common.JspHelper;
import org.apache.hadoop.hdfs.tools.DelegationTokenFetcher;
import org.apache.hadoop.hdfs.web.URLUtils;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.ipc.RemoteException;
import org.apache.hadoop.net.NetUtils;
import org.apache.hadoop.security.Credentials;
import org.apache.hadoop.security.SecurityUtil;
import org.apache.hadoop.security.UserGroupInformation;
import org.apache.hadoop.security.token.Token;
import org.apache.hadoop.security.token.TokenIdentifier;
import org.apache.hadoop.security.token.TokenRenewer;
import org.apache.hadoop.security.token.delegation.AbstractDelegationTokenSelector;
import org.apache.hadoop.util.Progressable;
import org.apache.hadoop.util.ServletUtil;
import org.xml.sax.Attributes;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
import org.xml.sax.helpers.DefaultHandler;
import org.xml.sax.helpers.XMLReaderFactory;
/**
* An implementation of a protocol for accessing filesystems over HTTP.
* The following implementation provides a limited, read-only interface
* to a filesystem over HTTP.
* @see org.apache.hadoop.hdfs.server.namenode.ListPathsServlet
* @see org.apache.hadoop.hdfs.server.namenode.FileDataServlet
*/
@InterfaceAudience.Private
@InterfaceStability.Evolving
public class HftpFileSystem extends FileSystem
implements DelegationTokenRenewer.Renewable {
static {
HttpURLConnection.setFollowRedirects(true);
}
public static final Text TOKEN_KIND = new Text("HFTP delegation");
protected UserGroupInformation ugi;
private URI hftpURI;
protected URI nnUri;
public static final String HFTP_TIMEZONE = "UTC";
public static final String HFTP_DATE_FORMAT = "yyyy-MM-dd'T'HH:mm:ssZ";
private Token<?> delegationToken;
private Token<?> renewToken;
private static final HftpDelegationTokenSelector hftpTokenSelector =
new HftpDelegationTokenSelector();
private DelegationTokenRenewer dtRenewer = null;
private synchronized void addRenewAction(final HftpFileSystem hftpFs) {
if (dtRenewer == null) {
dtRenewer = DelegationTokenRenewer.getInstance();
}
dtRenewer.addRenewAction(hftpFs);
}
public static final SimpleDateFormat getDateFormat() {
final SimpleDateFormat df = new SimpleDateFormat(HFTP_DATE_FORMAT);
df.setTimeZone(TimeZone.getTimeZone(HFTP_TIMEZONE));
return df;
}
protected static final ThreadLocal<SimpleDateFormat> df =
new ThreadLocal<SimpleDateFormat>() {
@Override
protected SimpleDateFormat initialValue() {
return getDateFormat();
}
};
@Override
protected int getDefaultPort() {
return getConf().getInt(DFSConfigKeys.DFS_NAMENODE_HTTP_PORT_KEY,
DFSConfigKeys.DFS_NAMENODE_HTTP_PORT_DEFAULT);
}
/**
* We generate the address with one of the following ports, in
* order of preference.
* 1. Port from the hftp URI e.g. hftp://namenode:4000/ will return 4000.
* 2. Port configured via DFS_NAMENODE_HTTP_PORT_KEY
* 3. DFS_NAMENODE_HTTP_PORT_DEFAULT i.e. 50070.
*
* @param uri
* @return
*/
protected InetSocketAddress getNamenodeAddr(URI uri) {
// use authority so user supplied uri can override port
return NetUtils.createSocketAddr(uri.getAuthority(), getDefaultPort());
}
protected URI getNamenodeUri(URI uri) {
return DFSUtil.createUri(getUnderlyingProtocol(), getNamenodeAddr(uri));
}
/**
* See the documentation of {@Link #getNamenodeAddr(URI)} for the logic
* behind selecting the canonical service name.
* @return
*/
@Override
public String getCanonicalServiceName() {
return SecurityUtil.buildTokenService(nnUri).toString();
}
@Override
protected URI canonicalizeUri(URI uri) {
return NetUtils.getCanonicalUri(uri, getDefaultPort());
}
/**
* Return the protocol scheme for the FileSystem.
* <p/>
*
* @return <code>hftp</code>
*/
@Override
public String getScheme() {
return "hftp";
}
@Override
public void initialize(final URI name, final Configuration conf)
throws IOException {
super.initialize(name, conf);
setConf(conf);
this.ugi = UserGroupInformation.getCurrentUser();
this.nnUri = getNamenodeUri(name);
try {
this.hftpURI = new URI(name.getScheme(), name.getAuthority(),
null, null, null);
} catch (URISyntaxException e) {
throw new IllegalArgumentException(e);
}
if (UserGroupInformation.isSecurityEnabled()) {
initDelegationToken();
}
}
protected void initDelegationToken() throws IOException {
// look for hftp token, then try hdfs
Token<?> token = selectDelegationToken(ugi);
// if we don't already have a token, go get one over https
boolean createdToken = false;
if (token == null) {
token = getDelegationToken(null);
createdToken = (token != null);
}
// we already had a token or getDelegationToken() didn't fail.
if (token != null) {
setDelegationToken(token);
if (createdToken) {
addRenewAction(this);
LOG.debug("Created new DT for " + token.getService());
} else {
LOG.debug("Found existing DT for " + token.getService());
}
}
}
protected Token<DelegationTokenIdentifier> selectDelegationToken(
UserGroupInformation ugi) {
return hftpTokenSelector.selectToken(nnUri, ugi.getTokens(), getConf());
}
@Override
public Token<?> getRenewToken() {
return renewToken;
}
/**
* Return the underlying protocol that is used to talk to the namenode.
*/
protected String getUnderlyingProtocol() {
return "http";
}
@Override
public synchronized <T extends TokenIdentifier> void setDelegationToken(Token<T> token) {
renewToken = token;
// emulate the 203 usage of the tokens
// by setting the kind and service as if they were hdfs tokens
delegationToken = new Token<T>(token);
// NOTE: the remote nn must be configured to use hdfs
delegationToken.setKind(DelegationTokenIdentifier.HDFS_DELEGATION_KIND);
// no need to change service because we aren't exactly sure what it
// should be. we can guess, but it might be wrong if the local conf
// value is incorrect. the service is a client side field, so the remote
// end does not care about the value
}
@Override
public synchronized Token<?> getDelegationToken(final String renewer
) throws IOException {
try {
//Renew TGT if needed
ugi.checkTGTAndReloginFromKeytab();
return ugi.doAs(new PrivilegedExceptionAction<Token<?>>() {
@Override
public Token<?> run() throws IOException {
final String nnHttpUrl = nnUri.toString();
Credentials c;
try {
c = DelegationTokenFetcher.getDTfromRemote(nnHttpUrl, renewer);
} catch (IOException e) {
if (e.getCause() instanceof ConnectException) {
LOG.warn("Couldn't connect to " + nnHttpUrl +
", assuming security is disabled");
return null;
}
if (LOG.isDebugEnabled()) {
LOG.debug("Exception getting delegation token", e);
}
throw e;
}
for (Token<? extends TokenIdentifier> t : c.getAllTokens()) {
if(LOG.isDebugEnabled()) {
LOG.debug("Got dt for " + getUri() + ";t.service="
+t.getService());
}
return t;
}
return null;
}
});
} catch (InterruptedException e) {
throw new RuntimeException(e);
}
}
@Override
public URI getUri() {
return hftpURI;
}
/**
* Return a URL pointing to given path on the namenode.
*
* @param path to obtain the URL for
* @param query string to append to the path
* @return namenode URL referring to the given path
* @throws IOException on error constructing the URL
*/
protected URL getNamenodeURL(String path, String query) throws IOException {
final URL url = new URL(getUnderlyingProtocol(), nnUri.getHost(),
nnUri.getPort(), path + '?' + query);
if (LOG.isTraceEnabled()) {
LOG.trace("url=" + url);
}
return url;
}
/**
* Get encoded UGI parameter string for a URL.
*
* @return user_shortname,group1,group2...
*/
private String getEncodedUgiParameter() {
StringBuilder ugiParamenter = new StringBuilder(
ServletUtil.encodeQueryValue(ugi.getShortUserName()));
for(String g: ugi.getGroupNames()) {
ugiParamenter.append(",");
ugiParamenter.append(ServletUtil.encodeQueryValue(g));
}
return ugiParamenter.toString();
}
/**
* Open an HTTP connection to the namenode to read file data and metadata.
* @param path The path component of the URL
* @param query The query component of the URL
*/
protected HttpURLConnection openConnection(String path, String query)
throws IOException {
query = addDelegationTokenParam(query);
final URL url = getNamenodeURL(path, query);
final HttpURLConnection connection =
(HttpURLConnection)URLUtils.openConnection(url);
connection.setRequestMethod("GET");
connection.connect();
return connection;
}
protected String addDelegationTokenParam(String query) throws IOException {
String tokenString = null;
if (UserGroupInformation.isSecurityEnabled()) {
synchronized (this) {
if (delegationToken != null) {
tokenString = delegationToken.encodeToUrlString();
return (query + JspHelper.getDelegationTokenUrlParam(tokenString));
}
}
}
return query;
}
static class RangeHeaderUrlOpener extends ByteRangeInputStream.URLOpener {
RangeHeaderUrlOpener(final URL url) {
super(url);
}
protected HttpURLConnection openConnection() throws IOException {
return (HttpURLConnection)URLUtils.openConnection(url);
}
/** Use HTTP Range header for specifying offset. */
@Override
protected HttpURLConnection connect(final long offset,
final boolean resolved) throws IOException {
final HttpURLConnection conn = openConnection();
conn.setRequestMethod("GET");
if (offset != 0L) {
conn.setRequestProperty("Range", "bytes=" + offset + "-");
}
conn.connect();
//Expects HTTP_OK or HTTP_PARTIAL response codes.
final int code = conn.getResponseCode();
if (offset != 0L && code != HttpURLConnection.HTTP_PARTIAL) {
throw new IOException("HTTP_PARTIAL expected, received " + code);
} else if (offset == 0L && code != HttpURLConnection.HTTP_OK) {
throw new IOException("HTTP_OK expected, received " + code);
}
return conn;
}
}
static class RangeHeaderInputStream extends ByteRangeInputStream {
RangeHeaderInputStream(RangeHeaderUrlOpener o, RangeHeaderUrlOpener r) {
super(o, r);
}
RangeHeaderInputStream(final URL url) {
this(new RangeHeaderUrlOpener(url), new RangeHeaderUrlOpener(null));
}
@Override
protected URL getResolvedUrl(final HttpURLConnection connection) {
return connection.getURL();
}
}
@Override
public FSDataInputStream open(Path f, int buffersize) throws IOException {
f = f.makeQualified(getUri(), getWorkingDirectory());
String path = "/data" + ServletUtil.encodePath(f.toUri().getPath());
String query = addDelegationTokenParam("ugi=" + getEncodedUgiParameter());
URL u = getNamenodeURL(path, query);
return new FSDataInputStream(new RangeHeaderInputStream(u));
}
@Override
public void close() throws IOException {
super.close();
if (dtRenewer != null) {
dtRenewer.removeRenewAction(this); // blocks
}
}
/** Class to parse and store a listing reply from the server. */
class LsParser extends DefaultHandler {
ArrayList<FileStatus> fslist = new ArrayList<FileStatus>();
@Override
public void startElement(String ns, String localname, String qname,
Attributes attrs) throws SAXException {
if ("listing".equals(qname)) return;
if (!"file".equals(qname) && !"directory".equals(qname)) {
if (RemoteException.class.getSimpleName().equals(qname)) {
throw new SAXException(RemoteException.valueOf(attrs));
}
throw new SAXException("Unrecognized entry: " + qname);
}
long modif;
long atime = 0;
try {
final SimpleDateFormat ldf = df.get();
modif = ldf.parse(attrs.getValue("modified")).getTime();
String astr = attrs.getValue("accesstime");
if (astr != null) {
atime = ldf.parse(astr).getTime();
}
} catch (ParseException e) { throw new SAXException(e); }
FileStatus fs = "file".equals(qname)
? new FileStatus(
Long.valueOf(attrs.getValue("size")).longValue(), false,
Short.valueOf(attrs.getValue("replication")).shortValue(),
Long.valueOf(attrs.getValue("blocksize")).longValue(),
modif, atime, FsPermission.valueOf(attrs.getValue("permission")),
attrs.getValue("owner"), attrs.getValue("group"),
HftpFileSystem.this.makeQualified(
new Path(getUri().toString(), attrs.getValue("path"))))
: new FileStatus(0L, true, 0, 0L,
modif, atime, FsPermission.valueOf(attrs.getValue("permission")),
attrs.getValue("owner"), attrs.getValue("group"),
HftpFileSystem.this.makeQualified(
new Path(getUri().toString(), attrs.getValue("path"))));
fslist.add(fs);
}
private void fetchList(String path, boolean recur) throws IOException {
try {
XMLReader xr = XMLReaderFactory.createXMLReader();
xr.setContentHandler(this);
HttpURLConnection connection = openConnection(
"/listPaths" + ServletUtil.encodePath(path),
"ugi=" + getEncodedUgiParameter() + (recur ? "&recursive=yes" : ""));
InputStream resp = connection.getInputStream();
xr.parse(new InputSource(resp));
} catch(SAXException e) {
final Exception embedded = e.getException();
if (embedded != null && embedded instanceof IOException) {
throw (IOException)embedded;
}
throw new IOException("invalid xml directory content", e);
}
}
public FileStatus getFileStatus(Path f) throws IOException {
fetchList(f.toUri().getPath(), false);
if (fslist.size() == 0) {
throw new FileNotFoundException("File does not exist: " + f);
}
return fslist.get(0);
}
public FileStatus[] listStatus(Path f, boolean recur) throws IOException {
fetchList(f.toUri().getPath(), recur);
if (fslist.size() > 0 && (fslist.size() != 1 || fslist.get(0).isDirectory())) {
fslist.remove(0);
}
return fslist.toArray(new FileStatus[0]);
}
public FileStatus[] listStatus(Path f) throws IOException {
return listStatus(f, false);
}
}
@Override
public FileStatus[] listStatus(Path f) throws IOException {
LsParser lsparser = new LsParser();
return lsparser.listStatus(f);
}
@Override
public FileStatus getFileStatus(Path f) throws IOException {
LsParser lsparser = new LsParser();
return lsparser.getFileStatus(f);
}
private class ChecksumParser extends DefaultHandler {
private FileChecksum filechecksum;
@Override
public void startElement(String ns, String localname, String qname,
Attributes attrs) throws SAXException {
if (!MD5MD5CRC32FileChecksum.class.getName().equals(qname)) {
if (RemoteException.class.getSimpleName().equals(qname)) {
throw new SAXException(RemoteException.valueOf(attrs));
}
throw new SAXException("Unrecognized entry: " + qname);
}
filechecksum = MD5MD5CRC32FileChecksum.valueOf(attrs);
}
private FileChecksum getFileChecksum(String f) throws IOException {
final HttpURLConnection connection = openConnection(
"/fileChecksum" + ServletUtil.encodePath(f),
"ugi=" + getEncodedUgiParameter());
try {
final XMLReader xr = XMLReaderFactory.createXMLReader();
xr.setContentHandler(this);
xr.parse(new InputSource(connection.getInputStream()));
} catch(SAXException e) {
final Exception embedded = e.getException();
if (embedded != null && embedded instanceof IOException) {
throw (IOException)embedded;
}
throw new IOException("invalid xml directory content", e);
} finally {
connection.disconnect();
}
return filechecksum;
}
}
@Override
public FileChecksum getFileChecksum(Path f) throws IOException {
final String s = makeQualified(f).toUri().getPath();
return new ChecksumParser().getFileChecksum(s);
}
@Override
public Path getWorkingDirectory() {
return new Path("/").makeQualified(getUri(), null);
}
@Override
public void setWorkingDirectory(Path f) { }
/** This optional operation is not yet supported. */
@Override
public FSDataOutputStream append(Path f, int bufferSize,
Progressable progress) throws IOException {
throw new IOException("Not supported");
}
@Override
public FSDataOutputStream create(Path f, FsPermission permission,
boolean overwrite, int bufferSize, short replication,
long blockSize, Progressable progress) throws IOException {
throw new IOException("Not supported");
}
@Override
public boolean rename(Path src, Path dst) throws IOException {
throw new IOException("Not supported");
}
@Override
public boolean delete(Path f, boolean recursive) throws IOException {
throw new IOException("Not supported");
}
@Override
public boolean mkdirs(Path f, FsPermission permission) throws IOException {
throw new IOException("Not supported");
}
/**
* A parser for parsing {@link ContentSummary} xml.
*/
private class ContentSummaryParser extends DefaultHandler {
private ContentSummary contentsummary;
@Override
public void startElement(String ns, String localname, String qname,
Attributes attrs) throws SAXException {
if (!ContentSummary.class.getName().equals(qname)) {
if (RemoteException.class.getSimpleName().equals(qname)) {
throw new SAXException(RemoteException.valueOf(attrs));
}
throw new SAXException("Unrecognized entry: " + qname);
}
contentsummary = toContentSummary(attrs);
}
/**
* Connect to the name node and get content summary.
* @param path The path
* @return The content summary for the path.
* @throws IOException
*/
private ContentSummary getContentSummary(String path) throws IOException {
final HttpURLConnection connection = openConnection(
"/contentSummary" + ServletUtil.encodePath(path),
"ugi=" + getEncodedUgiParameter());
InputStream in = null;
try {
in = connection.getInputStream();
final XMLReader xr = XMLReaderFactory.createXMLReader();
xr.setContentHandler(this);
xr.parse(new InputSource(in));
} catch(FileNotFoundException fnfe) {
//the server may not support getContentSummary
return null;
} catch(SAXException saxe) {
final Exception embedded = saxe.getException();
if (embedded != null && embedded instanceof IOException) {
throw (IOException)embedded;
}
throw new IOException("Invalid xml format", saxe);
} finally {
if (in != null) {
in.close();
}
connection.disconnect();
}
return contentsummary;
}
}
/** Return the object represented in the attributes. */
private static ContentSummary toContentSummary(Attributes attrs
) throws SAXException {
final String length = attrs.getValue("length");
final String fileCount = attrs.getValue("fileCount");
final String directoryCount = attrs.getValue("directoryCount");
final String quota = attrs.getValue("quota");
final String spaceConsumed = attrs.getValue("spaceConsumed");
final String spaceQuota = attrs.getValue("spaceQuota");
if (length == null
|| fileCount == null
|| directoryCount == null
|| quota == null
|| spaceConsumed == null
|| spaceQuota == null) {
return null;
}
try {
return new ContentSummary(
Long.parseLong(length),
Long.parseLong(fileCount),
Long.parseLong(directoryCount),
Long.parseLong(quota),
Long.parseLong(spaceConsumed),
Long.parseLong(spaceQuota));
} catch(Exception e) {
throw new SAXException("Invalid attributes: length=" + length
+ ", fileCount=" + fileCount
+ ", directoryCount=" + directoryCount
+ ", quota=" + quota
+ ", spaceConsumed=" + spaceConsumed
+ ", spaceQuota=" + spaceQuota, e);
}
}
@Override
public ContentSummary getContentSummary(Path f) throws IOException {
final String s = makeQualified(f).toUri().getPath();
final ContentSummary cs = new ContentSummaryParser().getContentSummary(s);
return cs != null? cs: super.getContentSummary(f);
}
@InterfaceAudience.Private
public static class TokenManager extends TokenRenewer {
@Override
public boolean handleKind(Text kind) {
return kind.equals(TOKEN_KIND);
}
@Override
public boolean isManaged(Token<?> token) throws IOException {
return true;
}
protected String getUnderlyingProtocol() {
return "http";
}
@SuppressWarnings("unchecked")
@Override
public long renew(Token<?> token,
Configuration conf) throws IOException {
// update the kerberos credentials, if they are coming from a keytab
UserGroupInformation.getLoginUser().checkTGTAndReloginFromKeytab();
InetSocketAddress serviceAddr = SecurityUtil.getTokenServiceAddr(token);
return
DelegationTokenFetcher.renewDelegationToken
(DFSUtil.createUri(getUnderlyingProtocol(), serviceAddr).toString(),
(Token<DelegationTokenIdentifier>) token);
}
@SuppressWarnings("unchecked")
@Override
public void cancel(Token<?> token,
Configuration conf) throws IOException {
// update the kerberos credentials, if they are coming from a keytab
UserGroupInformation.getLoginUser().checkTGTAndReloginFromKeytab();
InetSocketAddress serviceAddr = SecurityUtil.getTokenServiceAddr(token);
DelegationTokenFetcher.cancelDelegationToken
(DFSUtil.createUri(getUnderlyingProtocol(), serviceAddr).toString(),
(Token<DelegationTokenIdentifier>) token);
}
}
private static class HftpDelegationTokenSelector
extends AbstractDelegationTokenSelector<DelegationTokenIdentifier> {
private static final DelegationTokenSelector hdfsTokenSelector =
new DelegationTokenSelector();
public HftpDelegationTokenSelector() {
super(TOKEN_KIND);
}
Token<DelegationTokenIdentifier> selectToken(URI nnUri,
Collection<Token<?>> tokens, Configuration conf) {
Token<DelegationTokenIdentifier> token =
selectToken(SecurityUtil.buildTokenService(nnUri), tokens);
if (token == null) {
// try to get a HDFS token
token = hdfsTokenSelector.selectToken(nnUri, tokens, conf);
}
return token;
}
}
}