/** Generic request handler (GET+POST). */
protected void doRequest(
Event anEvent, HttpServletRequest request, HttpServletResponse response) {
// Must have valid event type.
String eventType = anEvent.getEventType();
try {
// Get Session: either by creating (on Join eventType)
// or by id (any other eventType, since client is supposed to have
// joined).
Session session = null;
if (eventType.startsWith(Protocol.E_JOIN)) {
// Join request: create new subscriber
session = SessionManager.getInstance().createSession(anEvent);
String userAgent = request.getHeader("User-Agent");
if (userAgent != null) {
userAgent = userAgent.toLowerCase();
} else {
userAgent = "unknown";
}
session.setUserAgent(userAgent);
} else {
// Must be a request for existing Session
// Get id
String id = anEvent.getField(P_ID);
// We must have an id value
if (id == null) {
response.sendError(HttpServletResponse.SC_BAD_REQUEST, "No id specified");
Log.warn("Pushlet: bad request, no id specified event=" + eventType);
return;
}
// We have an id: get the session object
session = SessionManager.getInstance().getSession(id);
// Check for invalid id
if (session == null) {
response.sendError(HttpServletResponse.SC_BAD_REQUEST, "Invalid or expired id: " + id);
Log.warn("Pushlet: bad request, no session found id=" + id + " event=" + eventType);
return;
}
}
// ASSERTION: we have a valid Session
// Let Controller handle request further
// including exceptions
Command command = Command.create(session, anEvent, request, response);
session.getController().doCommand(command);
} catch (Throwable t) {
// Hmm we should never ever get here
Log.warn("Pushlet: Exception in doRequest() event=" + eventType, t);
t.printStackTrace();
response.setStatus(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
}
}
public void init() throws ServletException {
try {
// Load configuration (from classpath or WEB-INF root path)
String webInfPath = getServletContext().getRealPath("/") + "/WEB-INF";
Config.load(webInfPath);
Log.init();
// Start
Log.info(
"init() Pushlet Webapp - version="
+ Version.SOFTWARE_VERSION
+ " built="
+ Version.BUILD_DATE);
// Start session manager
SessionManager.getInstance().start();
// Start event Dispatcher
Dispatcher.getInstance().start();
if (Config.getBoolProperty(Config.SOURCES_ACTIVATE)) {
EventSourceManager.start(webInfPath);
} else {
Log.info("Not starting local event sources");
}
} catch (Throwable t) {
throw new ServletException("Failed to initialize Pushlet framework " + t, t);
}
}
public void destroy() {
Log.info("destroy(): Exit Pushlet webapp");
if (Config.getBoolProperty(Config.SOURCES_ACTIVATE)) {
// Stop local event sources
EventSourceManager.stop();
} else {
Log.info("No local event sources to stop");
}
// Should abort all subscribers
Dispatcher.getInstance().stop();
// Should stop all sessions
SessionManager.getInstance().stop();
}
static {
// Singleton + factory pattern: create single instance
// from configured class name
try {
instance =
(SessionManager)
Config.getClass(SESSION_MANAGER_CLASS, "com.wondersgroup.eda.core.SessionManager")
.newInstance();
Log.info("SessionManager created className=" + instance.getClass());
} catch (Throwable t) {
Log.fatal("Cannot instantiate SessionManager from config", t);
}
}