/*
* 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;
/*****************************************************************************
* This code is based on the "HttpUploadServerHandler" from the
* Netty project's HTTP server example.
*
* See http://netty.io and
* https://github.com/netty/netty/blob/netty-4.0.31.Final/example/src/main/java/io/netty/example/http/upload/HttpUploadServerHandler.java
*****************************************************************************/
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelHandler;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.handler.codec.http.DefaultFullHttpResponse;
import io.netty.handler.codec.http.HttpContent;
import io.netty.handler.codec.http.HttpHeaders;
import io.netty.handler.codec.http.HttpMethod;
import io.netty.handler.codec.http.HttpObject;
import io.netty.handler.codec.http.HttpRequest;
import io.netty.handler.codec.http.HttpResponseStatus;
import io.netty.handler.codec.http.HttpVersion;
import io.netty.handler.codec.http.LastHttpContent;
import io.netty.handler.codec.http.QueryStringDecoder;
import io.netty.handler.codec.http.QueryStringEncoder;
import io.netty.handler.codec.http.multipart.DefaultHttpDataFactory;
import io.netty.handler.codec.http.multipart.DiskFileUpload;
import io.netty.handler.codec.http.multipart.HttpDataFactory;
import io.netty.handler.codec.http.multipart.HttpPostRequestDecoder;
import io.netty.handler.codec.http.multipart.HttpPostRequestDecoder.EndOfDataDecoderException;
import io.netty.handler.codec.http.multipart.InterfaceHttpData;
import io.netty.handler.codec.http.multipart.InterfaceHttpData.HttpDataType;
import org.apache.flink.configuration.ConfigConstants;
import org.apache.flink.util.ExceptionUtils;
import java.io.File;
import java.io.IOException;
import java.nio.charset.Charset;
import java.util.UUID;
/**
* Simple code which handles all HTTP requests from the user, and passes them to the Router
* handler directly if they do not involve file upload requests.
* If a file is required to be uploaded, it handles the upload, and in the http request to the
* next handler, passes the name of the file to the next handler.
*/
@ChannelHandler.Sharable
public class HttpRequestHandler extends SimpleChannelInboundHandler<HttpObject> {
private static final Charset ENCODING = ConfigConstants.DEFAULT_CHARSET;
/** A decoder factory that always stores POST chunks on disk */
private static final HttpDataFactory DATA_FACTORY = new DefaultHttpDataFactory(true);
private final File tmpDir;
private HttpRequest currentRequest;
private HttpPostRequestDecoder currentDecoder;
private String currentRequestPath;
public HttpRequestHandler(File tmpDir) {
this.tmpDir = tmpDir;
}
@Override
public void channelUnregistered(ChannelHandlerContext ctx) throws Exception {
if (currentDecoder != null) {
currentDecoder.cleanFiles();
}
}
@Override
public void channelRead0(ChannelHandlerContext ctx, HttpObject msg) {
try {
if (msg instanceof HttpRequest) {
currentRequest = (HttpRequest) msg;
currentRequestPath = null;
if (currentDecoder != null) {
currentDecoder.destroy();
currentDecoder = null;
}
if (currentRequest.getMethod() == HttpMethod.GET || currentRequest.getMethod() == HttpMethod.DELETE) {
// directly delegate to the router
ctx.fireChannelRead(currentRequest);
}
else if (currentRequest.getMethod() == HttpMethod.POST) {
// POST comes in multiple objects. First the request, then the contents
// keep the request and path for the remaining objects of the POST request
currentRequestPath = new QueryStringDecoder(currentRequest.getUri(), ENCODING).path();
currentDecoder = new HttpPostRequestDecoder(DATA_FACTORY, currentRequest, ENCODING);
}
else {
throw new IOException("Unsupported HTTP method: " + currentRequest.getMethod().name());
}
}
else if (currentDecoder != null && msg instanceof HttpContent) {
// received new chunk, give it to the current decoder
HttpContent chunk = (HttpContent) msg;
currentDecoder.offer(chunk);
try {
while (currentDecoder.hasNext()) {
InterfaceHttpData data = currentDecoder.next();
// IF SOMETHING EVER NEEDS POST PARAMETERS, THIS WILL BE THE PLACE TO HANDLE IT
// all fields values will be passed with type Attribute.
if (data.getHttpDataType() == HttpDataType.FileUpload) {
DiskFileUpload file = (DiskFileUpload) data;
if (file.isCompleted()) {
String name = file.getFilename();
File target = new File(tmpDir, UUID.randomUUID() + "_" + name);
file.renameTo(target);
QueryStringEncoder encoder = new QueryStringEncoder(currentRequestPath);
encoder.addParam("filepath", target.getAbsolutePath());
encoder.addParam("filename", name);
currentRequest.setUri(encoder.toString());
}
}
data.release();
}
}
catch (EndOfDataDecoderException ignored) {}
if (chunk instanceof LastHttpContent) {
HttpRequest request = currentRequest;
currentRequest = null;
currentRequestPath = null;
currentDecoder.destroy();
currentDecoder = null;
// fire next channel handler
ctx.fireChannelRead(request);
}
}
}
catch (Throwable t) {
currentRequest = null;
currentRequestPath = null;
if (currentDecoder != null) {
currentDecoder.destroy();
currentDecoder = null;
}
if (ctx.channel().isActive()) {
byte[] bytes = ExceptionUtils.stringifyException(t).getBytes(ENCODING);
DefaultFullHttpResponse response = new DefaultFullHttpResponse(
HttpVersion.HTTP_1_1, HttpResponseStatus.INTERNAL_SERVER_ERROR,
Unpooled.wrappedBuffer(bytes));
response.headers().set(HttpHeaders.Names.CONTENT_TYPE, "text/plain");
response.headers().set(HttpHeaders.Names.CONTENT_LENGTH, response.content().readableBytes());
ctx.writeAndFlush(response);
}
}
}
}