2 * Jalview - A Sequence Alignment Editor and Viewer ($$Version-Rel$$)
3 * Copyright (C) $$Year-Rel$$ The Jalview Authors
5 * This file is part of Jalview.
7 * Jalview is free software: you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation, either version 3
10 * of the License, or (at your option) any later version.
12 * Jalview is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty
14 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR
15 * PURPOSE. See the GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with Jalview. If not, see <http://www.gnu.org/licenses/>.
19 * The Jalview Authors are detailed in the 'AUTHORS' file.
21 package jalview.httpserver;
23 import jalview.bin.Jalview;
24 import jalview.rest.RestHandler;
26 import java.net.BindException;
28 import java.util.Collections;
29 import java.util.HashMap;
32 import javax.servlet.http.HttpServletRequest;
33 import javax.servlet.http.HttpServletResponse;
35 import org.eclipse.jetty.server.Handler;
36 import org.eclipse.jetty.server.Server;
37 import org.eclipse.jetty.server.ServerConnector;
38 import org.eclipse.jetty.server.handler.ContextHandler;
39 import org.eclipse.jetty.server.handler.HandlerCollection;
40 import org.eclipse.jetty.util.thread.QueuedThreadPool;
43 * An HttpServer built on Jetty. To use it
45 * <li>call getInstance() to create and start the server</li>
46 * <li>call registerHandler to add a handler for a path (below /jalview)</li>
47 * <li>when finished, call removedHandler</li>
51 * @see http://eclipse.org/jetty/documentation/current/embedding-jetty.html
53 public class HttpServer
56 * 'context root' - actually just prefixed to the path for each handler for
57 * now - see registerHandler
59 private static final String JALVIEW_PATH = "jalview";
62 * Returns the singleton instance of this class.
65 * @throws BindException
67 public static HttpServer getInstance() throws BindException
69 synchronized (HttpServer.class)
71 Jalview j = Jalview.getInstance();
72 return (j.httpServer == null ? j.httpServer = new HttpServer()
80 private Server server;
83 * Registered handlers for context paths
85 private HandlerCollection contextHandlers;
88 * Lookup of ContextHandler by its wrapped handler
90 Map<Handler, ContextHandler> myHandlers = new HashMap<>();
93 * The context root for the server
95 private URI contextRoot;
98 * Private constructor to enforce use of singleton
100 * @throws BindException
101 * if no free port can be assigned
103 private HttpServer() throws BindException
108 * Provides a REST server by default; add more programmatically as required
110 registerHandler(RestHandler.getInstance());
114 * Start the http server
116 * @throws BindException
118 private void startServer() throws BindException
123 * Create a server with a small number of threads; jetty will allocate a
126 QueuedThreadPool tp = new QueuedThreadPool(4, 1); // max, min
127 server = new Server(tp);
128 // 2 selector threads to handle incoming connections
129 ServerConnector connector = new ServerConnector(server, 0, 2);
130 // restrict to localhost
131 connector.setHost("localhost");
132 server.addConnector(connector);
135 * HttpServer shuts down with Jalview process
137 server.setStopAtShutdown(true);
140 * Create a mutable set of handlers (can add handlers while the server is
141 * running). Using vanilla handlers here rather than servlets
143 // TODO how to properly configure context root "/jalview"
144 contextHandlers = new HandlerCollection(true);
145 server.setHandler(contextHandlers);
147 // System.out.println(String.format(
148 // "HttpServer started with %d threads", server.getThreadPool()
150 contextRoot = server.getURI();
151 } catch (Exception e)
154 "Error trying to start HttpServer: " + e.getMessage());
158 } catch (Exception e1)
160 e1.printStackTrace();
165 throw new BindException("HttpServer failed to allocate a port");
170 * Returns the URI on which we are listening
176 return server == null ? null : server.getURI();
180 * For debug - write HTTP request details to stdout
185 protected void dumpRequest(HttpServletRequest request,
186 HttpServletResponse response)
188 for (String hdr : Collections.list(request.getHeaderNames()))
190 for (String val : Collections.list(request.getHeaders(hdr)))
192 System.out.println(hdr + ": " + val);
195 for (String param : Collections.list(request.getParameterNames()))
197 for (String val : request.getParameterValues(param))
199 System.out.println(param + "=" + val);
205 * Stop the Http server.
207 public void stopServer()
211 if (server.isStarted())
216 } catch (Exception e)
218 System.err.println("Error stopping Http Server on "
219 + server.getURI() + ": " + e.getMessage());
226 * Register a handler for the given path and set its URI
230 * @throws IllegalStateException
231 * if handler path has not been set
233 public void registerHandler(AbstractRequestHandler handler)
235 String path = handler.getPath();
238 throw new IllegalStateException(
239 "Must set handler path before registering handler");
242 // http://stackoverflow.com/questions/20043097/jetty-9-embedded-adding-handlers-during-runtime
243 ContextHandler ch = new ContextHandler();
244 ch.setAllowNullPathInfo(true);
245 ch.setContextPath("/" + JALVIEW_PATH + "/" + path);
246 ch.setResourceBase(".");
247 ch.setClassLoader(Thread.currentThread().getContextClassLoader());
248 ch.setHandler(handler);
251 * Remember the association so we can remove it later
253 this.myHandlers.put(handler, ch);
256 * A handler added to a running server must be started explicitly
258 contextHandlers.addHandler(ch);
262 } catch (Exception e)
265 "Error starting handler for " + path + ": " + e.getMessage());
268 handler.setUri(this.contextRoot + ch.getContextPath().substring(1));
269 System.out.println("Jalview " + handler.getName()
270 + " handler started on " + handler.getUri());
274 * Removes the handler from the server; more precisely, remove the
275 * ContextHandler wrapping the specified handler
279 public void removeHandler(AbstractRequestHandler handler)
282 * Have to use this cached lookup table since there is no method
283 * ContextHandler.getHandler()
285 ContextHandler ch = myHandlers.get(handler);
288 contextHandlers.removeHandler(ch);
289 myHandlers.remove(handler);
290 System.out.println("Stopped Jalview " + handler.getName()
291 + " handler on " + handler.getUri());