/*
* 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.flink.runtime.webmonitor.files;
/*****************************************************************************
* This code is based on the "HttpStaticFileServerHandler" from the
* Netty project's HTTP server example.
*
* See http://netty.io and
* https://github.com/netty/netty/blob/4.0/example/src/main/java/io/netty/example/http/file/HttpStaticFileServerHandler.java
*****************************************************************************/
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelHandler;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.DefaultFileRegion;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.handler.codec.http.DefaultFullHttpResponse;
import io.netty.handler.codec.http.DefaultHttpResponse;
import io.netty.handler.codec.http.FullHttpResponse;
import io.netty.handler.codec.http.HttpChunkedInput;
import io.netty.handler.codec.http.HttpHeaders;
import io.netty.handler.codec.http.HttpRequest;
import io.netty.handler.codec.http.HttpResponse;
import io.netty.handler.codec.http.HttpResponseStatus;
import io.netty.handler.codec.http.LastHttpContent;
import io.netty.handler.codec.http.router.KeepAliveWrite;
import io.netty.handler.codec.http.router.Routed;
import io.netty.handler.ssl.SslHandler;
import io.netty.handler.stream.ChunkedFile;
import io.netty.util.CharsetUtil;
import org.apache.flink.runtime.instance.ActorGateway;
import org.apache.flink.runtime.webmonitor.JobManagerRetriever;
import org.apache.flink.runtime.webmonitor.handlers.HandlerRedirectUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import scala.Option;
import scala.Tuple2;
import scala.concurrent.Await;
import scala.concurrent.Future;
import scala.concurrent.duration.FiniteDuration;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.RandomAccessFile;
import java.net.URI;
import java.net.URISyntaxException;
import java.net.URL;
import java.nio.file.Files;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;
import java.util.Locale;
import java.util.TimeZone;
import static io.netty.handler.codec.http.HttpHeaders.Names.CACHE_CONTROL;
import static io.netty.handler.codec.http.HttpHeaders.Names.CONNECTION;
import static io.netty.handler.codec.http.HttpHeaders.Names.CONTENT_TYPE;
import static io.netty.handler.codec.http.HttpHeaders.Names.DATE;
import static io.netty.handler.codec.http.HttpHeaders.Names.EXPIRES;
import static io.netty.handler.codec.http.HttpHeaders.Names.IF_MODIFIED_SINCE;
import static io.netty.handler.codec.http.HttpHeaders.Names.LAST_MODIFIED;
import static io.netty.handler.codec.http.HttpResponseStatus.INTERNAL_SERVER_ERROR;
import static io.netty.handler.codec.http.HttpResponseStatus.NOT_FOUND;
import static io.netty.handler.codec.http.HttpResponseStatus.NOT_MODIFIED;
import static io.netty.handler.codec.http.HttpResponseStatus.OK;
import static io.netty.handler.codec.http.HttpVersion.HTTP_1_1;
import static org.apache.flink.util.Preconditions.checkNotNull;
/**
* Simple file server handler that serves requests to web frontend's static files, such as
* HTML, CSS, or JS files.
*
* <p>This code is based on the "HttpStaticFileServerHandler" from the Netty project's HTTP server
* example.</p>
*/
@ChannelHandler.Sharable
public class StaticFileServerHandler extends SimpleChannelInboundHandler<Routed> {
/** Default logger, if none is specified */
private static final Logger DEFAULT_LOGGER = LoggerFactory.getLogger(StaticFileServerHandler.class);
/** Timezone in which this server answers its "if-modified" requests */
private static final TimeZone GMT_TIMEZONE = TimeZone.getTimeZone("GMT");
/** Date format for HTTP */
public static final String HTTP_DATE_FORMAT = "EEE, dd MMM yyyy HH:mm:ss zzz";
/** Be default, we allow files to be cached for 5 minutes */
private static final int HTTP_CACHE_SECONDS = 300;
// ------------------------------------------------------------------------
/** JobManager retriever */
private final JobManagerRetriever retriever;
private final Future<String> localJobManagerAddressFuture;
private final FiniteDuration timeout;
/** The path in which the static documents are */
private final File rootPath;
/** Whether the web service has https enabled */
private final boolean httpsEnabled;
/** The log for all error reporting */
private final Logger logger;
private String localJobManagerAddress;
public StaticFileServerHandler(
JobManagerRetriever retriever,
Future<String> localJobManagerAddressPromise,
FiniteDuration timeout,
File rootPath,
boolean httpsEnabled) throws IOException {
this(retriever, localJobManagerAddressPromise, timeout, rootPath, httpsEnabled, DEFAULT_LOGGER);
}
public StaticFileServerHandler(
JobManagerRetriever retriever,
Future<String> localJobManagerAddressFuture,
FiniteDuration timeout,
File rootPath,
boolean httpsEnabled,
Logger logger) throws IOException {
this.retriever = checkNotNull(retriever);
this.localJobManagerAddressFuture = checkNotNull(localJobManagerAddressFuture);
this.timeout = checkNotNull(timeout);
this.rootPath = checkNotNull(rootPath).getCanonicalFile();
this.httpsEnabled = httpsEnabled;
this.logger = checkNotNull(logger);
}
// ------------------------------------------------------------------------
// Responses to requests
// ------------------------------------------------------------------------
@Override
public void channelRead0(ChannelHandlerContext ctx, Routed routed) throws Exception {
if (localJobManagerAddressFuture.isCompleted()) {
if (localJobManagerAddress == null) {
localJobManagerAddress = Await.result(localJobManagerAddressFuture, timeout);
}
final HttpRequest request = routed.request();
String requestPath = routed.path();
// make sure we request the "index.html" in case there is a directory request
if (requestPath.endsWith("/")) {
requestPath = requestPath + "index.html";
}
// in case the files being accessed are logs or stdout files, find appropriate paths.
if (requestPath.equals("/jobmanager/log") || requestPath.equals("/jobmanager/stdout")) {
requestPath = "";
}
Option<Tuple2<ActorGateway, Integer>> jobManager = retriever.getJobManagerGatewayAndWebPort();
if (jobManager.isDefined()) {
// Redirect to leader if necessary
String redirectAddress = HandlerRedirectUtils.getRedirectAddress(
localJobManagerAddress, jobManager.get());
if (redirectAddress != null) {
HttpResponse redirect = HandlerRedirectUtils.getRedirectResponse(
redirectAddress, requestPath, httpsEnabled);
KeepAliveWrite.flush(ctx, routed.request(), redirect);
}
else {
respondAsLeader(ctx, request, requestPath);
}
}
else {
KeepAliveWrite.flush(ctx, routed.request(), HandlerRedirectUtils.getUnavailableResponse());
}
} else {
KeepAliveWrite.flush(ctx, routed.request(), HandlerRedirectUtils.getUnavailableResponse());
}
}
/**
* Response when running with leading JobManager.
*/
private void respondAsLeader(ChannelHandlerContext ctx, HttpRequest request, String requestPath)
throws IOException, ParseException, URISyntaxException {
// convert to absolute path
final File file = new File(rootPath, requestPath);
if (!file.exists()) {
// file does not exist. Try to load it with the classloader
ClassLoader cl = StaticFileServerHandler.class.getClassLoader();
try(InputStream resourceStream = cl.getResourceAsStream("web" + requestPath)) {
boolean success = false;
try {
if (resourceStream != null) {
URL root = cl.getResource("web");
URL requested = cl.getResource("web" + requestPath);
if (root != null && requested != null) {
URI rootURI = new URI(root.getPath()).normalize();
URI requestedURI = new URI(requested.getPath()).normalize();
// Check that we don't load anything from outside of the
// expected scope.
if (!rootURI.relativize(requestedURI).equals(requestedURI)) {
logger.debug("Loading missing file from classloader: {}", requestPath);
// ensure that directory to file exists.
file.getParentFile().mkdirs();
Files.copy(resourceStream, file.toPath());
success = true;
}
}
}
} catch (Throwable t) {
logger.error("error while responding", t);
} finally {
if (!success) {
logger.debug("Unable to load requested file {} from classloader", requestPath);
sendError(ctx, NOT_FOUND);
return;
}
}
}
}
if (!file.exists() || file.isHidden() || file.isDirectory() || !file.isFile()) {
sendError(ctx, NOT_FOUND);
return;
}
if (!file.getCanonicalFile().toPath().startsWith(rootPath.toPath())) {
sendError(ctx, NOT_FOUND);
return;
}
// cache validation
final String ifModifiedSince = request.headers().get(IF_MODIFIED_SINCE);
if (ifModifiedSince != null && !ifModifiedSince.isEmpty()) {
SimpleDateFormat dateFormatter = new SimpleDateFormat(HTTP_DATE_FORMAT, Locale.US);
Date ifModifiedSinceDate = dateFormatter.parse(ifModifiedSince);
// Only compare up to the second because the datetime format we send to the client
// does not have milliseconds
long ifModifiedSinceDateSeconds = ifModifiedSinceDate.getTime() / 1000;
long fileLastModifiedSeconds = file.lastModified() / 1000;
if (ifModifiedSinceDateSeconds == fileLastModifiedSeconds) {
if (logger.isDebugEnabled()) {
logger.debug("Responding 'NOT MODIFIED' for file '" + file.getAbsolutePath() + '\'');
}
sendNotModified(ctx);
return;
}
}
if (logger.isDebugEnabled()) {
logger.debug("Responding with file '" + file.getAbsolutePath() + '\'');
}
// Don't need to close this manually. Netty's DefaultFileRegion will take care of it.
final RandomAccessFile raf;
try {
raf = new RandomAccessFile(file, "r");
}
catch (FileNotFoundException e) {
sendError(ctx, NOT_FOUND);
return;
}
try {
long fileLength = raf.length();
HttpResponse response = new DefaultHttpResponse(HTTP_1_1, OK);
setContentTypeHeader(response, file);
// since the log and out files are rapidly changing, we don't want to browser to cache them
if (!(requestPath.contains("log") || requestPath.contains("out"))) {
setDateAndCacheHeaders(response, file);
}
if (HttpHeaders.isKeepAlive(request)) {
response.headers().set(CONNECTION, HttpHeaders.Values.KEEP_ALIVE);
}
HttpHeaders.setContentLength(response, fileLength);
// write the initial line and the header.
ctx.write(response);
// write the content.
ChannelFuture lastContentFuture;
if (ctx.pipeline().get(SslHandler.class) == null) {
ctx.write(new DefaultFileRegion(raf.getChannel(), 0, fileLength), ctx.newProgressivePromise());
lastContentFuture = ctx.writeAndFlush(LastHttpContent.EMPTY_LAST_CONTENT);
} else {
lastContentFuture = ctx.writeAndFlush(new HttpChunkedInput(new ChunkedFile(raf, 0, fileLength, 8192)),
ctx.newProgressivePromise());
// HttpChunkedInput will write the end marker (LastHttpContent) for us.
}
// close the connection, if no keep-alive is needed
if (!HttpHeaders.isKeepAlive(request)) {
lastContentFuture.addListener(ChannelFutureListener.CLOSE);
}
} catch (Exception e) {
raf.close();
logger.error("Failed to serve file.", e);
sendError(ctx, INTERNAL_SERVER_ERROR);
}
}
@Override
public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {
if (ctx.channel().isActive()) {
logger.error("Caught exception", cause);
sendError(ctx, INTERNAL_SERVER_ERROR);
}
}
// ------------------------------------------------------------------------
// Utilities to encode headers and responses
// ------------------------------------------------------------------------
/**
* Writes a simple error response message.
*
* @param ctx The channel context to write the response to.
* @param status The response status.
*/
public static void sendError(ChannelHandlerContext ctx, HttpResponseStatus status) {
FullHttpResponse response = new DefaultFullHttpResponse(
HTTP_1_1, status, Unpooled.copiedBuffer("Failure: " + status + "\r\n", CharsetUtil.UTF_8));
response.headers().set(CONTENT_TYPE, "text/plain; charset=UTF-8");
// close the connection as soon as the error message is sent.
ctx.writeAndFlush(response).addListener(ChannelFutureListener.CLOSE);
}
/**
* Send the "304 Not Modified" response. This response can be used when the
* file timestamp is the same as what the browser is sending up.
*
* @param ctx The channel context to write the response to.
*/
public static void sendNotModified(ChannelHandlerContext ctx) {
FullHttpResponse response = new DefaultFullHttpResponse(HTTP_1_1, NOT_MODIFIED);
setDateHeader(response);
// close the connection as soon as the error message is sent.
ctx.writeAndFlush(response).addListener(ChannelFutureListener.CLOSE);
}
/**
* Sets the "date" header for the HTTP response.
*
* @param response HTTP response
*/
public static void setDateHeader(FullHttpResponse response) {
SimpleDateFormat dateFormatter = new SimpleDateFormat(HTTP_DATE_FORMAT, Locale.US);
dateFormatter.setTimeZone(GMT_TIMEZONE);
Calendar time = new GregorianCalendar();
response.headers().set(DATE, dateFormatter.format(time.getTime()));
}
/**
* Sets the "date" and "cache" headers for the HTTP Response.
*
* @param response The HTTP response object.
* @param fileToCache File to extract the modification timestamp from.
*/
public static void setDateAndCacheHeaders(HttpResponse response, File fileToCache) {
SimpleDateFormat dateFormatter = new SimpleDateFormat(HTTP_DATE_FORMAT, Locale.US);
dateFormatter.setTimeZone(GMT_TIMEZONE);
// date header
Calendar time = new GregorianCalendar();
response.headers().set(DATE, dateFormatter.format(time.getTime()));
// cache headers
time.add(Calendar.SECOND, HTTP_CACHE_SECONDS);
response.headers().set(EXPIRES, dateFormatter.format(time.getTime()));
response.headers().set(CACHE_CONTROL, "private, max-age=" + HTTP_CACHE_SECONDS);
response.headers().set(LAST_MODIFIED, dateFormatter.format(new Date(fileToCache.lastModified())));
}
/**
* Sets the content type header for the HTTP Response.
*
* @param response HTTP response
* @param file file to extract content type
*/
public static void setContentTypeHeader(HttpResponse response, File file) {
String mimeType = MimeTypes.getMimeTypeForFileName(file.getName());
String mimeFinal = mimeType != null ? mimeType : MimeTypes.getDefaultMimeType();
response.headers().set(CONTENT_TYPE, mimeFinal);
}
}