esens.wp6.ibmJmsBackend.log4http.HttpLogServerHandler.java Source code

Introduction

Here is the source code for esens.wp6.ibmJmsBackend.log4http.HttpLogServerHandler.java

Source

/*
 * Copyright 2013 The Netty Project
 *
 * The Netty Project 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 esens.wp6.ibmJmsBackend.log4http;

import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelHandlerAdapter;
import io.netty.channel.ChannelHandlerContext;
import io.netty.handler.codec.http.DefaultFullHttpResponse;
import io.netty.handler.codec.http.FullHttpResponse;
import io.netty.handler.codec.http.HttpHeaderUtil;
import io.netty.handler.codec.http.HttpHeaderValues;
import io.netty.handler.codec.http.HttpRequest;
import org.apache.log4j.Logger;

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.io.StringWriter;

import static io.netty.handler.codec.http.HttpHeaderNames.*;
import static io.netty.handler.codec.http.HttpResponseStatus.*;
import static io.netty.handler.codec.http.HttpVersion.*;

public class HttpLogServerHandler extends ChannelHandlerAdapter {
    private static final Logger LOGGER = Logger.getLogger(HttpLogServerHandler.class);

    @Override
    public void channelReadComplete(ChannelHandlerContext ctx) {
        ctx.flush();
    }

    @Override
    public void channelRead(ChannelHandlerContext ctx, Object msg) {
        if (msg instanceof HttpRequest) {
            HttpRequest req = (HttpRequest) msg;

            if (HttpHeaderUtil.is100ContinueExpected(req)) {
                ctx.write(new DefaultFullHttpResponse(HTTP_1_1, CONTINUE));
            }
            boolean keepAlive = HttpHeaderUtil.isKeepAlive(req);
            System.out.println(req.uri());

            //get number of lines to show from the request uri.

            String lines = "-n 500"; //pull last 500 lines as default
            if (req.uri().equals("/")) {
                //all lines
            } else {
                try {
                    lines = "-n " + Integer.parseInt(req.uri().substring(1));
                } catch (NumberFormatException ex) {

                }
            }
            //LOGGER.debug("# of lines to tail \"" + lines + "\"");
            /**
             * *********** DOES NOT WORK ON WINDOWS because uses tail command
             */
            StringWriter sw = new StringWriter();
            PrintWriter pw = new PrintWriter(sw);
            try {
                final Process exec = Runtime.getRuntime().exec("tail " + lines + " logs/ibm-jms-backend.log");

                BufferedReader br = new BufferedReader(new InputStreamReader(exec.getInputStream()));

                String line = null;

                while ((line = br.readLine()) != null) {
                    pw.println(line);
                }
            } catch (Exception ex) {
                LOGGER.error("Couldn't run tail, are you using Windows (smirk)");
                pw.println("Couldn't run tail, are you using Windows (smirk)");
                LOGGER.error(ex.getMessage(), ex);
                ex.printStackTrace(pw);
            }

            FullHttpResponse response = new DefaultFullHttpResponse(HTTP_1_1, OK,
                    Unpooled.wrappedBuffer(sw.toString().getBytes()));
            response.headers().set(CONTENT_TYPE, "text/plain");
            response.headers().setInt(CONTENT_LENGTH, response.content().readableBytes());

            if (!keepAlive) {
                ctx.write(response).addListener(ChannelFutureListener.CLOSE);
            } else {
                response.headers().set(CONNECTION, HttpHeaderValues.KEEP_ALIVE);
                ctx.write(response);
            }
        }
    }

    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {
        cause.printStackTrace();
        ctx.close();
    }
}