/*
* 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.history;
/*****************************************************************************
* 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.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.DefaultHttpResponse;
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.LastHttpContent;
import io.netty.handler.codec.http.router.Routed;
import io.netty.handler.ssl.SslHandler;
import io.netty.handler.stream.ChunkedFile;
import org.apache.flink.runtime.webmonitor.files.StaticFileServerHandler;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
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.URL;
import java.nio.file.Files;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Locale;
import static io.netty.handler.codec.http.HttpHeaders.Names.CONNECTION;
import static io.netty.handler.codec.http.HttpHeaders.Names.IF_MODIFIED_SINCE;
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.OK;
import static io.netty.handler.codec.http.HttpVersion.HTTP_1_1;
import static org.apache.flink.util.Preconditions.checkNotNull;
/**
* Simple file server handler used by the {@link HistoryServer} that serves requests to web frontend's static files,
* such as HTML, CSS, JS or JSON files.
*
* This code is based on the "HttpStaticFileServerHandler" from the Netty project's HTTP server
* example.
*
* This class is a copy of the {@link StaticFileServerHandler}. The differences are that the request path is
* modified to end on ".json" if it does not have a filename extension; when "index.html" is requested we load
* "index_hs.html" instead to inject the modified HistoryServer WebInterface and that the caching of the "/joboverview"
* page is prevented.
*/
@ChannelHandler.Sharable
public class HistoryServerStaticFileServerHandler extends SimpleChannelInboundHandler<Routed> {
/** Default logger, if none is specified */
private static final Logger LOG = LoggerFactory.getLogger(HistoryServerStaticFileServerHandler.class);
// ------------------------------------------------------------------------
/** The path in which the static documents are */
private final File rootPath;
public HistoryServerStaticFileServerHandler(File rootPath) throws IOException {
this.rootPath = checkNotNull(rootPath).getCanonicalFile();
}
// ------------------------------------------------------------------------
// Responses to requests
// ------------------------------------------------------------------------
@Override
public void channelRead0(ChannelHandlerContext ctx, Routed routed) throws Exception {
String requestPath = routed.path();
respondWithFile(ctx, routed.request(), requestPath);
}
/**
* Response when running with leading JobManager.
*/
private void respondWithFile(ChannelHandlerContext ctx, HttpRequest request, String requestPath)
throws IOException, ParseException {
// make sure we request the "index.html" in case there is a directory request
if (requestPath.endsWith("/")) {
requestPath = requestPath + "index.html";
}
if (!requestPath.contains(".")) { // we assume that the path ends in either .html or .js
requestPath = requestPath + ".json";
}
// 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 = HistoryServerStaticFileServerHandler.class.getClassLoader();
String pathToLoad = requestPath.replace("index.html", "index_hs.html");
try (InputStream resourceStream = cl.getResourceAsStream("web" + pathToLoad)) {
boolean success = false;
try {
if (resourceStream != null) {
URL root = cl.getResource("web");
URL requested = cl.getResource("web" + pathToLoad);
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)) {
LOG.debug("Loading missing file from classloader: {}", pathToLoad);
// ensure that directory to file exists.
file.getParentFile().mkdirs();
Files.copy(resourceStream, file.toPath());
success = true;
}
}
}
} catch (Throwable t) {
LOG.error("error while responding", t);
} finally {
if (!success) {
LOG.debug("Unable to load requested file {} from classloader", pathToLoad);
StaticFileServerHandler.sendError(ctx, NOT_FOUND);
return;
}
}
}
}
if (!file.exists() || file.isHidden() || file.isDirectory() || !file.isFile()) {
StaticFileServerHandler.sendError(ctx, NOT_FOUND);
return;
}
if (!file.getCanonicalFile().toPath().startsWith(rootPath.toPath())) {
StaticFileServerHandler.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(StaticFileServerHandler.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 (LOG.isDebugEnabled()) {
LOG.debug("Responding 'NOT MODIFIED' for file '" + file.getAbsolutePath() + '\'');
}
StaticFileServerHandler.sendNotModified(ctx);
return;
}
}
if (LOG.isDebugEnabled()) {
LOG.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) {
StaticFileServerHandler.sendError(ctx, NOT_FOUND);
return;
}
try {
long fileLength = raf.length();
HttpResponse response = new DefaultHttpResponse(HTTP_1_1, OK);
StaticFileServerHandler.setContentTypeHeader(response, file);
// the job overview should be updated as soon as possible
if (!requestPath.equals("/joboverview.json")) {
StaticFileServerHandler.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();
LOG.error("Failed to serve file.", e);
StaticFileServerHandler.sendError(ctx, INTERNAL_SERVER_ERROR);
}
}
@Override
public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {
if (ctx.channel().isActive()) {
LOG.error("Caught exception", cause);
StaticFileServerHandler.sendError(ctx, INTERNAL_SERVER_ERROR);
}
}
}