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.Instance;
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
57 * Returns the singleton instance of this class.
60 * @throws BindException
62 public static HttpServer getInstance() throws BindException
64 synchronized (HttpServer.class)
66 Instance j = Instance.getInstance();
67 return (j.httpServer == null ? j.httpServer = new HttpServer()
73 * Private constructor to enforce use of singleton; use getInstance().
75 * @throws BindException
76 * if no free port can be assigned
78 private HttpServer() throws BindException
85 * Provides a REST server by default; add more programmatically as required
87 registerHandler(RestHandler.getInstance());
91 * 'context root' - actually just prefixed to the path for each handler for
92 * now - see registerHandler
94 private static final String JALVIEW_PATH = "jalview";
99 private Server server;
102 * Registered handlers for context paths
104 private HandlerCollection contextHandlers;
107 * Lookup of ContextHandler by its wrapped handler
109 Map<Handler, ContextHandler> myHandlers = new HashMap<>();
112 * The context root for the server
114 private URI contextRoot;
117 * Start the http server
119 * @throws BindException
121 private void startServer() throws BindException
126 * Create a server with a small number of threads; jetty will allocate a
129 QueuedThreadPool tp = new QueuedThreadPool(4, 1); // max, min
130 server = new Server(tp);
131 // 2 selector threads to handle incoming connections
132 ServerConnector connector = new ServerConnector(server, 0, 2);
133 // restrict to localhost
134 connector.setHost("localhost");
135 server.addConnector(connector);
138 * HttpServer shuts down with Jalview process
140 server.setStopAtShutdown(true);
143 * Create a mutable set of handlers (can add handlers while the server is
144 * running). Using vanilla handlers here rather than servlets
146 // TODO how to properly configure context root "/jalview"
147 contextHandlers = new HandlerCollection(true);
148 server.setHandler(contextHandlers);
150 // System.out.println(String.format(
151 // "HttpServer started with %d threads", server.getThreadPool()
153 contextRoot = server.getURI();
154 } catch (Exception e)
157 "Error trying to start HttpServer: " + e.getMessage());
161 } catch (Exception e1)
163 e1.printStackTrace();
168 throw new BindException("HttpServer failed to allocate a port");
173 * Returns the URI on which we are listening
179 return server == null ? null : server.getURI();
183 * For debug - write HTTP request details to stdout
188 protected void dumpRequest(HttpServletRequest request,
189 HttpServletResponse response)
191 for (String hdr : Collections.list(request.getHeaderNames()))
193 for (String val : Collections.list(request.getHeaders(hdr)))
195 System.out.println(hdr + ": " + val);
198 for (String param : Collections.list(request.getParameterNames()))
200 for (String val : request.getParameterValues(param))
202 System.out.println(param + "=" + val);
208 * Stop the Http server.
210 public void stopServer()
214 if (server.isStarted())
219 } catch (Exception e)
221 System.err.println("Error stopping Http Server on "
222 + server.getURI() + ": " + e.getMessage());
229 * Register a handler for the given path and set its URI
233 * @throws IllegalStateException
234 * if handler path has not been set
236 public void registerHandler(AbstractRequestHandler handler)
238 String path = handler.getPath();
241 throw new IllegalStateException(
242 "Must set handler path before registering handler");
245 // http://stackoverflow.com/questions/20043097/jetty-9-embedded-adding-handlers-during-runtime
246 ContextHandler ch = new ContextHandler();
247 ch.setAllowNullPathInfo(true);
248 ch.setContextPath("/" + JALVIEW_PATH + "/" + path);
249 ch.setResourceBase(".");
250 ch.setClassLoader(Thread.currentThread().getContextClassLoader());
251 ch.setHandler(handler);
254 * Remember the association so we can remove it later
256 this.myHandlers.put(handler, ch);
259 * A handler added to a running server must be started explicitly
261 contextHandlers.addHandler(ch);
265 } catch (Exception e)
268 "Error starting handler for " + path + ": " + e.getMessage());
271 handler.setUri(this.contextRoot + ch.getContextPath().substring(1));
272 System.out.println("Jalview " + handler.getName()
273 + " handler started on " + handler.getUri());
277 * Removes the handler from the server; more precisely, remove the
278 * ContextHandler wrapping the specified handler
282 public void removeHandler(AbstractRequestHandler handler)
285 * Have to use this cached lookup table since there is no method
286 * ContextHandler.getHandler()
288 ContextHandler ch = myHandlers.get(handler);
291 contextHandlers.removeHandler(ch);
292 myHandlers.remove(handler);
293 System.out.println("Stopped Jalview " + handler.getName()
294 + " handler on " + handler.getUri());