Java tutorial
/** 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 com.heliosapm.streams.metrichub.tsdbplugin; import java.io.File; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.RandomAccessFile; import java.net.URL; import java.nio.charset.Charset; import java.util.Enumeration; import java.util.List; import java.util.Map; import java.util.concurrent.TimeUnit; import java.util.jar.JarEntry; import java.util.jar.JarFile; import org.apache.logging.log4j.LogManager; import org.apache.logging.log4j.Logger; import org.jboss.netty.buffer.ChannelBuffer; import org.jboss.netty.buffer.ChannelBuffers; import org.jboss.netty.buffer.DirectChannelBufferFactory; import org.jboss.netty.buffer.HeapChannelBufferFactory; import org.jboss.netty.buffer.ReadOnlyChannelBuffer; import org.jboss.netty.channel.Channel; import org.jboss.netty.channel.ChannelFuture; import org.jboss.netty.channel.ChannelFutureListener; import org.jboss.netty.channel.DefaultFileRegion; import org.jboss.netty.handler.codec.http.DefaultHttpResponse; import org.jboss.netty.handler.codec.http.HttpHeaders; import org.jboss.netty.handler.codec.http.HttpResponseStatus; import org.jboss.netty.handler.codec.http.HttpVersion; import com.codahale.metrics.Timer; import com.heliosapm.streams.metrichub.HubManager; import com.heliosapm.streams.metrichub.MetricsMetaAPI; import com.heliosapm.utils.buffer.BufferManager; import com.heliosapm.utils.mime.MimeTypeManager; import com.stumbleupon.async.Deferred; import io.netty.buffer.ByteBuf; import net.opentsdb.core.TSDB; import net.opentsdb.stats.StatsCollector; import net.opentsdb.tsd.HttpRpcPlugin; import net.opentsdb.tsd.HttpRpcPluginQuery; /** * <p>Title: MetricsAPIHttpPlugin</p> * <p>Description: Initilizes the MetricsAPI service and registers handlers to serve the metrics api UI content.</p> * @author Whitehead (nwhitehead AT heliosdev DOT org) * <p><code>com.heliosapm.streams.metrichub.tsdbplugin.MetricsAPIHttpPlugin</code></p> */ public class MetricsAPIHttpPlugin extends HttpRpcPlugin { /** Instance logger */ private final Logger log = LogManager.getLogger(getClass()); /** The metric manager for this plugin */ protected final PluginMetricManager metricManager = new PluginMetricManager(getClass().getSimpleName()); /** Timer for statci content serves */ protected final Timer timer = metricManager.timer("static-content-time"); /** A reference to the metrics api service instance */ protected MetricsMetaAPI metricsMetaAPI = null; /** The JSON based remoting interface to the metrics api service */ protected JSONMetricsAPIService jsonMetricsService = null; /** The parent TSDB instance */ protected TSDB tsdb = null; /* The location of the metric api UI content */ protected File metricUiContentDir = null; /** Indicates if this class originates in a jar or directory (dev) */ protected final boolean inJar; /** The mime type determiner */ protected final MimeTypeManager mimeTypes = MimeTypeManager.getInstance(); /** A heap buffer factory */ protected static final HeapChannelBufferFactory heapBuffFactory = new HeapChannelBufferFactory(); /** A direct buffer factory */ protected static final DirectChannelBufferFactory directBuffFactory = new DirectChannelBufferFactory(); /** The content base to load resources from the classpath */ public static final String CONTENT_BASE = "/metricapi-ui"; /** The uri for requests to be handled by this plugin */ public static final String MAPI = "/metricapi"; /** The uri for requests for static UI content to be handled by this plugin */ public static final String MAPI_CONTENT = "/metricapi/s"; /** The UTF8 character set */ public static final Charset UTF8 = Charset.forName("UTF8"); private static final byte[] NOT_FOUND_BYTES = "NOT FOUND".getBytes(UTF8); /** The cache entry for not found content lookups */ public static final ChannelBuffer NOTFOUND_PLACEHOLDER = new ReadOnlyChannelBuffer( heapBuffFactory.getBuffer(NOT_FOUND_BYTES, 0, NOT_FOUND_BYTES.length)); /** This class's class loader */ public static final ClassLoader CL = MetricsAPIHttpPlugin.class.getClassLoader(); /** Content type to use for matching a serializer to incoming requests */ public static String request_content_type = "application/json"; /** Content type to return with data from this serializer */ public static String response_content_type = "application/json; charset=UTF-8"; /** * Creates a new MetricsAPIHttpPlugin */ public MetricsAPIHttpPlugin() { inJar = getClass().getProtectionDomain().getCodeSource().getLocation().toString().endsWith(".jar"); } /** * {@inheritDoc} * @see net.opentsdb.tsd.HttpRpcPlugin#initialize(net.opentsdb.core.TSDB) */ @Override public void initialize(final TSDB tsdb) { log.info(">>>>> Initializing MetricsAPIHttpPlugin...."); this.tsdb = tsdb; findContentDir(); metricsMetaAPI = HubManager.getInstance().getMetricMetaService(); jsonMetricsService = new JSONMetricsAPIService(metricsMetaAPI); log.info("<<<<< MetricsAPIHttpPlugin Initialized."); } /** * Assigns the metric api ui content directory */ protected void findContentDir() { if (inJar) { final String _staticContentDirName = tsdb.getConfig().getDirectoryName("tsd.http.staticroot"); final File _staticContentDir = new File(_staticContentDirName); if (!_staticContentDir.isDirectory()) { throw new IllegalArgumentException( "No static content directory found (defined by tsd.http.staticroot or --staticroot=)"); } metricUiContentDir = new File(_staticContentDir, "metricapi-ui"); if (!metricUiContentDir.isDirectory()) { if (!metricUiContentDir.exists()) { if (!metricUiContentDir.mkdir()) throw new IllegalArgumentException( "Failed to create metricapi-ui directory [" + metricUiContentDir + "]"); } throw new IllegalArgumentException( "Cannot create metricapi-ui directory [" + metricUiContentDir + "]"); } unloadFromJar(new File(getClass().getProtectionDomain().getCodeSource().getLocation().getFile())); } else { URL contentUrl = getClass().getClassLoader().getResource(CONTENT_BASE); if (contentUrl == null) throw new IllegalArgumentException( "No directory based resource found in classpath for resource [" + CONTENT_BASE + "]"); metricUiContentDir = new File(contentUrl.getFile()).getAbsoluteFile(); if (!metricUiContentDir.isDirectory()) throw new IllegalArgumentException( "Resource found for [" + CONTENT_BASE + "] : [" + contentUrl + "] was not a directory"); } } /** * {@inheritDoc} * @see net.opentsdb.tsd.HttpRpcPlugin#shutdown() */ @Override public Deferred<Object> shutdown() { return Deferred.fromResult(null); } /** * {@inheritDoc} * @see net.opentsdb.tsd.HttpRpcPlugin#version() */ @Override public String version() { return "2.2"; } /** * {@inheritDoc} * @see net.opentsdb.tsd.HttpRpcPlugin#collectStats(net.opentsdb.stats.StatsCollector) */ @Override public void collectStats(final StatsCollector collector) { metricManager.collectStats(collector); } /** * {@inheritDoc} * @see net.opentsdb.tsd.HttpRpcPlugin#getPath() */ @Override public String getPath() { return MAPI; } /** * {@inheritDoc} * @see net.opentsdb.tsd.HttpRpcPlugin#execute(net.opentsdb.core.TSDB, net.opentsdb.tsd.HttpRpcPluginQuery) */ @Override public void execute(final TSDB tsdb, final HttpRpcPluginQuery query) throws IOException { log.info("HTTP Query: [{}]", query.getQueryBaseRoute()); final String baseURI = query.request().getUri(); // ================================================================== // If baseURI is MAPI_CONTENT, then serve static content // Otherwise delegate to metric api service // ================================================================== query.notFound(); // if(CONTENT_BASE.equals(baseURI)) { // sendFile(CONTENT_BASE + "/index.html", 0); // return; // } // final String uri = baseURI.replace("metricapi-ui/", ""); // if ("/favicon.ico".equals(uri)) { // sendFile(staticDir // + "/favicon.ico", 31536000 /*=1yr*/); // return; // } // if (uri.length() < 3) { // Must be at least 3 because of the "/s/". // throw new RuntimeException("URI too short <code>" + uri + "</code>"); // } // // Cheap security check to avoid directory traversal attacks. // // TODO(tsuna): This is certainly not sufficient. // if (uri.indexOf("..", 3) > 0) { // throw new RuntimeException("Malformed URI <code>" + uri + "</code>"); // } // final int questionmark = uri.indexOf('?', 3); // final int pathend = questionmark > 0 ? questionmark : uri.length(); // sendFile(contentDir + "/" // + uri.substring(1, pathend), // Drop the "/s" // uri.contains("nocache") ? 0 : 31536000 /*=1yr*/); } /** * Send a file (with zero-copy) to the client with a 200 OK status. * This method doesn't provide any security guarantee. The caller is * responsible for the argument they pass in. * @param path The path to the file to send to the client. * @param max_age The expiration time of this entity, in seconds. This is * not a timestamp, it's how old the resource is allowed to be in the client * cache. See RFC 2616 section 14.9 for more information. Use 0 to disable * caching. */ public void sendFile(final HttpRpcPluginQuery query, final String path, final int max_age) throws IOException { sendFile(query, HttpResponseStatus.OK, path, max_age); } /** * Send a file to the client. * This method doesn't provide any security guarantee. The caller is * responsible for the argument they pass in. * @param query The query being processed * @param status The status of the request (e.g. 200 OK or 404 Not Found). * @param path The path to the file to send to the client. * @param max_age The expiration time of this entity, in seconds. This is * not a timestamp, it's how old the resource is allowed to be in the client * cache. See RFC 2616 section 14.9 for more information. Use 0 to disable * caching. */ public void sendFile(final HttpRpcPluginQuery query, final HttpResponseStatus status, final String path, final int max_age) throws IOException { if (max_age < 0) { throw new IllegalArgumentException("Negative max_age=" + max_age + " for path=" + path); } final Channel chan = query.channel(); if (!chan.isConnected()) { query.done(); return; } final Map<String, List<String>> querystring = query.getQueryString(); RandomAccessFile file = null; try { try { file = new RandomAccessFile(path, "r"); } catch (FileNotFoundException e) { log.warn("File not found: " + e.getMessage()); if (querystring != null) { querystring.remove("png"); // Avoid potential recursion. } query.notFound(); //sendBuffer(HttpResponseStatus.NOT_FOUND, formatNotFoundV1(query), response_content_type); return; } final long length = file.length(); final DefaultHttpResponse response = new DefaultHttpResponse(HttpVersion.HTTP_1_1, status); { response.headers().set(HttpHeaders.Names.CONTENT_TYPE, mimeTypes.getMimeTypeForPath(path, "text/plain")); final long mtime = new File(path).lastModified(); if (mtime > 0) { response.headers().set(HttpHeaders.Names.AGE, (System.currentTimeMillis() - mtime) / 1000); } else { log.warn("Found a file with mtime=" + mtime + ": " + path); } response.headers().set(HttpHeaders.Names.CACHE_CONTROL, "max-age=" + max_age); HttpHeaders.setContentLength(response, length); chan.write(response); } final DefaultFileRegion region = new DefaultFileRegion(file.getChannel(), 0, length); final ChannelFuture future = chan.write(region); future.addListener(new ChannelFutureListener() { public void operationComplete(final ChannelFuture future) { region.releaseExternalResources(); final long elapsed = query.processingTimeMillis(); timer.update(elapsed, TimeUnit.MILLISECONDS); } }); if (!HttpHeaders.isKeepAlive(query.request())) { future.addListener(ChannelFutureListener.CLOSE); } } finally { if (file != null) try { file.close(); } catch (Exception x) { /* No Op */} } } /** * Formats a 404 error when an endpoint or file wasn't found * <p> * <b>WARNING:</b> If overriding, make sure this method catches all errors and * returns a byte array with a simple string error at the minimum * @return A standard JSON error */ public ChannelBuffer formatNotFoundV1(final HttpRpcPluginQuery query) { StringBuilder output = new StringBuilder(1024); if (query.hasQueryStringParam("jsonp")) { output.append(query.getQueryStringParam("jsonp") + "("); } output.append("{\"error\":{\"code\":"); output.append(404); output.append(",\"message\":\""); output.append("Endpoint not found"); output.append("\"}}"); if (query.hasQueryStringParam("jsonp")) { output.append(")"); } return ChannelBuffers.copiedBuffer(output.toString().getBytes(query.getCharset())); } /** * Unloads the UI content from a jar * @param file The jar file */ protected void unloadFromJar(final File file) { log.info("Loading MetricsAPI UI Content from JAR: [{}]", file); final long startTime = System.currentTimeMillis(); int filesLoaded = 0; int fileFailures = 0; int fileNewer = 0; long bytesLoaded = 0; JarFile jar = null; final ByteBuf contentBuffer = BufferManager.getInstance().directBuffer(30000); try { jar = new JarFile(file); final Enumeration<JarEntry> entries = jar.entries(); while (entries.hasMoreElements()) { JarEntry entry = entries.nextElement(); final String name = entry.getName(); if (name.startsWith(CONTENT_BASE + "/")) { final int contentSize = (int) entry.getSize(); final long contentTime = entry.getTime(); if (entry.isDirectory()) { new File(metricUiContentDir, name).mkdirs(); continue; } File contentFile = new File(metricUiContentDir, name.replace(CONTENT_BASE + "/", "")); if (!contentFile.getParentFile().exists()) { contentFile.getParentFile().mkdirs(); } if (contentFile.exists()) { if (contentFile.lastModified() >= contentTime) { log.debug("File in directory was newer [{}]", name); fileNewer++; continue; } contentFile.delete(); } log.debug("Writing content file [{}]", contentFile); contentFile.createNewFile(); if (!contentFile.canWrite()) { log.warn("Content file [{}] not writable", contentFile); fileFailures++; continue; } FileOutputStream fos = null; InputStream jis = null; try { fos = new FileOutputStream(contentFile); jis = jar.getInputStream(entry); contentBuffer.writeBytes(jis, contentSize); contentBuffer.readBytes(fos, contentSize); fos.flush(); jis.close(); jis = null; fos.close(); fos = null; filesLoaded++; bytesLoaded += contentSize; log.debug("Wrote content file [{}] + with size [{}]", contentFile, contentSize); } finally { if (jis != null) try { jis.close(); } catch (Exception ex) { } if (fos != null) try { fos.close(); } catch (Exception ex) { } contentBuffer.clear(); } } // not content } // end of while loop final long elapsed = System.currentTimeMillis() - startTime; StringBuilder b = new StringBuilder( "\n\n\t===================================================\n\tMetricsAPI Content Directory:[") .append(metricUiContentDir).append("]"); b.append("\n\tTotal Files Written:").append(filesLoaded); b.append("\n\tTotal Bytes Written:").append(bytesLoaded); b.append("\n\tFile Write Failures:").append(fileFailures); b.append("\n\tExisting File Newer Than Content:").append(fileNewer); b.append("\n\tElapsed (ms):").append(elapsed); b.append("\n\t===================================================\n"); log.info(b.toString()); } catch (Exception ex) { log.error("Failed to export MetricsAPI content", ex); } finally { if (jar != null) try { jar.close(); } catch (Exception x) { /* No Op */} try { contentBuffer.release(); } catch (Exception x) { /* No Op */} } } }