--- a/src/java/de/uapcore/lightpit/ModuleManager.java Sun Apr 08 16:51:15 2018 +0200
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,231 +0,0 @@
-/*
- * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
- *
- * Copyright 2018 Mike Becker. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are met:
- *
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
- * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
- * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
- * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
- * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- *
- */
-package de.uapcore.lightpit;
-
-import de.uapcore.lightpit.entities.CoreDAOFactory;
-import de.uapcore.lightpit.entities.Module;
-import de.uapcore.lightpit.entities.ModuleDao;
-import java.sql.Connection;
-import java.sql.SQLException;
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.Optional;
-import java.util.concurrent.atomic.AtomicBoolean;
-import java.util.stream.Collectors;
-import javax.servlet.Registration;
-import javax.servlet.ServletContext;
-import javax.servlet.ServletContextEvent;
-import javax.servlet.ServletContextListener;
-import javax.servlet.annotation.WebListener;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-/**
- * Scans registered servlets for LightPIT modules.
- */
-@WebListener
-public final class ModuleManager implements ServletContextListener {
-
- private static final Logger LOG = LoggerFactory.getLogger(ModuleManager.class);
-
- /**
- * The attribute name in the servlet context under which an instance of this class can be found.
- */
- public static final String SC_ATTR_NAME = ModuleManager.class.getName();
- private ServletContext sc;
-
- /**
- * Maps class names to module information.
- */
- private final Map<String, LightPITModule> registeredModules = new HashMap<>();
-
- /**
- * This flag is true, when synchronization is needed.
- */
- private final AtomicBoolean dirty = new AtomicBoolean(true);
-
- @Override
- public void contextInitialized(ServletContextEvent sce) {
- sc = sce.getServletContext();
- reloadAll();
- sc.setAttribute(SC_ATTR_NAME, this);
- LOG.info("Module manager injected into ServletContext.");
- }
-
- @Override
- public void contextDestroyed(ServletContextEvent sce) {
- unloadAll();
- }
-
- private Optional<LightPITModule> getModuleInfo(Registration reg) {
- try {
- final Class scclass = Class.forName(reg.getClassName());
-
- final boolean lpservlet = AbstractLightPITServlet.class.isAssignableFrom(scclass);
- final boolean lpmodule = scclass.isAnnotationPresent(LightPITModule.class);
-
- if (lpservlet && !lpmodule) {
- LOG.warn(
- "{} is a LightPIT Servlet but is missing the module annotation.",
- reg.getClassName()
- );
- } else if (!lpservlet && lpmodule) {
- LOG.warn(
- "{} is annotated as a LightPIT Module but does not extend {}.",
- reg.getClassName(),
- AbstractLightPITServlet.class.getSimpleName()
- );
- }
-
- if (lpservlet && lpmodule) {
- final Class<? extends AbstractLightPITServlet> clazz = scclass;
- final LightPITModule moduleInfo = clazz.getAnnotation(LightPITModule.class);
- return Optional.of(moduleInfo);
- } else {
- return Optional.empty();
- }
- } catch (ClassNotFoundException ex) {
- LOG.error(
- "Servlet registration refers to class {} which cannot be found by the class loader (Reason: {})",
- reg.getClassName(),
- ex.getMessage()
- );
- return Optional.empty();
- }
- }
-
- private void handleServletRegistration(String name, Registration reg) {
- final Optional<LightPITModule> moduleInfo = getModuleInfo(reg);
- if (moduleInfo.isPresent()) {
- registeredModules.put(reg.getClassName(), moduleInfo.get());
- LOG.info("Module detected: {}", name);
- } else {
- LOG.debug("Servlet {} is no module, skipping.", name);
- }
- }
-
- /**
- * Scans for modules and reloads them all.
- */
- public void reloadAll() {
- registeredModules.clear();
- sc.getServletRegistrations().forEach(this::handleServletRegistration);
-
- // TODO: implement dependency resolver
-
- dirty.set(true);
- LOG.info("Modules loaded.");
- }
-
- /**
- * Synchronizes module information with the database.
- *
- * This must be called from the {@link AbstractLightPITServlet}.
- * Admittedly the call will perform the synchronization once after reload
- * and be a no-op, afterwards.
- * However, we since the DatabaseFacade might be loaded after the module
- * manager, we must defer the synchronization to the first request
- * handled by the Servlet.
- *
- * @param db interface to the database
- */
- public void syncWithDatabase(DatabaseFacade db) {
- if (dirty.compareAndSet(true, false)) {
- if (db.getDataSource().isPresent()) {
- try (Connection conn = db.getDataSource().get().getConnection()) {
- final ModuleDao moduleDao = CoreDAOFactory.getModuleDao(db.getSQLDialect());
- moduleDao.syncRegisteredModuleClasses(conn, registeredModules.entrySet());
- } catch (SQLException ex) {
- LOG.error("Unexpected SQL Exception", ex);
- }
- } else {
- LOG.error("No datasource present. Cannot sync module information with database.");
- }
- } else {
- LOG.trace("Module information clean - no synchronization required.");
- }
- }
-
- /**
- * Unloads all found modules.
- */
- public void unloadAll() {
- registeredModules.clear();
- LOG.info("All modules unloaded.");
- }
-
- /**
- * Returns the main menu.
- *
- * @param db the interface to the database
- * @return a list of menus belonging to the main menu
- */
- public List<Menu> getMainMenu(DatabaseFacade db) {
- // TODO: user specific menu
-
- if (db.getDataSource().isPresent()) {
- try (Connection conn = db.getDataSource().get().getConnection()) {
- final ModuleDao dao = CoreDAOFactory.getModuleDao(db.getSQLDialect());
- final List<Module> modules = dao.listAll(conn);
-
- final List<Menu> menu = modules
- .stream()
- .filter((mod) -> mod.isVisible())
- .collect(Collectors.mapping(
- (mod) -> new Menu(
- mod.getClassname(),
- new ResourceKey(
- registeredModules.get(mod.getClassname()).bundleBaseName(),
- registeredModules.get(mod.getClassname()).menuKey()),
- registeredModules.get(mod.getClassname()).modulePath()),
- Collectors.toList())
- );
- return menu;
- } catch (SQLException ex) {
- LOG.error("Unexpected SQLException when loading the main menu", ex);
- return Collections.emptyList();
- }
- } else {
- return Collections.emptyList();
- }
- }
-
- /**
- * Returns an unmodifiable map of all registered modules.
- *
- * The key is the classname of the module.
- *
- * @return the map of registered modules
- */
- public Map<String, LightPITModule> getRegisteredModules() {
- return Collections.unmodifiableMap(registeredModules);
- }
-}