SpringContextService.java
/*
* Copyright (c) 2002-2022, City of Paris
* 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
* and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice
* and the following disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* 3. Neither the name of 'Mairie de Paris' nor 'Lutece' nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* 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 HOLDERS 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.
*
* License 1.0
*/
package fr.paris.lutece.portal.service.spring;
import java.io.File;
import java.io.FilenameFilter;
import java.util.ArrayList;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.servlet.ServletContext;
import org.apache.commons.lang3.StringUtils;
import org.springframework.beans.factory.xml.XmlBeanDefinitionReader;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.AbstractApplicationContext;
import org.springframework.web.context.support.GenericWebApplicationContext;
import fr.paris.lutece.portal.service.init.LuteceInitException;
import fr.paris.lutece.portal.service.plugin.Plugin;
import fr.paris.lutece.portal.service.plugin.PluginEvent;
import fr.paris.lutece.portal.service.plugin.PluginEventListener;
import fr.paris.lutece.portal.service.plugin.PluginService;
import fr.paris.lutece.portal.service.util.AppLogService;
import fr.paris.lutece.portal.service.util.AppPathService;
/**
* This class provides a way to use Spring Framework ligthweight containers offering IoC (Inversion of Control) features.
*
* @see <a href= "http://www.springframework.org">http://www.springframework.org</a>
*/
public final class SpringContextService implements PluginEventListener
{
private static final String PROTOCOL_FILE = "file:";
private static final String PATH_CONF = "/WEB-INF/conf/";
private static final String DIR_PLUGINS = "plugins/";
private static final String DIR_OVERRIDE = "override/";
private static final String DIR_OVERRIDE_PLUGINS = DIR_OVERRIDE + DIR_PLUGINS;
private static final String SUFFIX_CONTEXT_FILE = "_context.xml";
private static final String FILE_CORE_CONTEXT = "core_context.xml";
private static ApplicationContext _context;
private static Map<Class, List> _mapBeansOfType = new HashMap<>( );
private static SpringContextService _instance = new SpringContextService( );
/** Creates a new instance of SpringContextService */
private SpringContextService( )
{
}
/**
* Return an instance, which may be shared or independent, of the given bean name. This method allows a Spring BeanFactory to be used as a replacement for
* the Singleton or Prototype design pattern.<br>
* The bean is retreived from the main context defined in the WEB-INF/conf/core_context.xml.
*
* @param <T>
* the generic type
* @param strName
* The bean's name
* @return The instance of the bean
*/
public static <T> T getBean( String strName )
{
return (T) _context.getBean( strName );
}
/**
* Return an instance of the given bean name loaded by the a Spring BeanFactory. The bean is retreived from a plugin context defined in the
* WEB-INF/conf/plugins/[plugin_name]_context.xml.
*
* @param strPluginName
* The Plugin's name
* @param strName
* The bean's name
* @return The instance of the bean
* @deprecated use {@link #getBean(String)} instead
*/
@Deprecated
public static Object getPluginBean( String strPluginName, String strName )
{
return _context.getBean( strName );
}
/**
* Indicates if a bean, referenced by its name, is part of an enabled plugin.
*
* Per Lutece convention, the plugin is determined from the bean's name prefix. If no prefix is present, the bean is considered enabled.
*
* @param strBeanName
* The bean's name
* @return <code>true</code> if the bean is part of an enabled plugin, <code>false</code> otherwise
*/
public static boolean isBeanEnabled( String strBeanName )
{
String strPrefix = getPrefix( strBeanName );
return strPrefix == null || isEnabled( strPrefix );
}
/**
* Initialize a global Application Context containing all beans (core + plugins) Now uses GenericApplicationContext for better performances. A wrong
* formatted file will not block block context to be built (without the file), but a wrong bean (i.e. cannot be instantiated) will cause a full context
* failure. Context is less "failure-friendly"
*
* @param servletContext
* The servlet context
* @throws LuteceInitException
* The lutece init exception
* @since 2.4
*/
public static void init( ServletContext servletContext ) throws LuteceInitException
{
try
{
// Register this service as a PluginEventListener
PluginService.registerPluginEventListener( _instance );
// timing
Date dateBegin = new Date( );
// Load the core context file : core_context.xml
String strConfPath = AppPathService.getAbsolutePathFromRelativePath( PATH_CONF );
String strContextFile = PROTOCOL_FILE + strConfPath + FILE_CORE_CONTEXT;
GenericWebApplicationContext gwac = new GenericWebApplicationContext( servletContext );
gwac.setId( getContextName( servletContext ) );
XmlBeanDefinitionReader xmlReader = new XmlBeanDefinitionReader( gwac );
xmlReader.loadBeanDefinitions( strContextFile );
AppLogService.info( "Context file loaded : {}", FILE_CORE_CONTEXT );
// Load all context files found in the conf/plugins directory
// Files are loaded separatly with an individual try/catch block
// to avoid stopping the process in case of a failure
// The global context generation will fail if a bean in any file cannot be
// built.
String strConfPluginsPath = strConfPath + DIR_PLUGINS;
File dirConfPlugins = new File( strConfPluginsPath );
FilenameFilter filterContext = new ContextFileFilter( );
String [ ] filesContext = dirConfPlugins.list( filterContext );
loadContexts( filesContext, strConfPluginsPath, xmlReader );
// we now load overriding beans
AppLogService.info( "Loading plugins context overrides" );
String strCoreContextOverrideFile = strConfPath + DIR_OVERRIDE + FILE_CORE_CONTEXT;
File fileCoreContextOverride = new File( strCoreContextOverrideFile );
if ( fileCoreContextOverride.exists( ) )
{
AppLogService.debug( "Context file loaded : core_context" );
xmlReader.loadBeanDefinitions( PROTOCOL_FILE + strCoreContextOverrideFile );
}
else
{
AppLogService.debug( "No core_context override found" );
}
// load plugins overrides
String strConfPluginsOverridePath = strConfPath + DIR_OVERRIDE_PLUGINS;
File dirConfOverridePlugins = new File( strConfPluginsOverridePath );
if ( dirConfOverridePlugins.exists( ) )
{
String [ ] filesOverrideContext = dirConfOverridePlugins.list( filterContext );
loadContexts( filesOverrideContext, strConfPluginsOverridePath, xmlReader );
}
gwac.refresh( );
_context = gwac;
AppLogService.info( "Spring context loaded in {} ms", ( ) -> ( new Date( ).getTime( ) - dateBegin.getTime( ) ) );
}
catch( Exception e )
{
AppLogService.error( "Error initializing Spring Context Service {}", e.getMessage( ), e );
throw new LuteceInitException( "Error initializing Spring Context Service", e );
}
}
/**
* Returns a name for this context
*
* @param servletContext
* the servlet context
* @return name for this context
*/
private static String getContextName( ServletContext servletContext )
{
String name = "lutece";
if ( servletContext != null )
{
String contextName = servletContext.getServletContextName( );
if ( contextName == null )
{
contextName = servletContext.getContextPath( );
}
if ( StringUtils.isNotBlank( contextName ) )
{
name = contextName;
}
}
return name;
}
/**
* Loads plugins contexts.
*
* @param filesContext
* context files names
* @param strConfPluginsPath
* full path
* @param xmlReader
* the xml reader
*/
private static void loadContexts( String [ ] filesContext, String strConfPluginsPath, XmlBeanDefinitionReader xmlReader )
{
if ( filesContext != null )
{
for ( String fileContext : filesContext )
{
String [ ] file = {
PROTOCOL_FILE + strConfPluginsPath + fileContext
};
// Safe loading of plugin context file
try
{
xmlReader.loadBeanDefinitions( file );
AppLogService.info( "Context file loaded : {}", fileContext );
}
catch( Exception e )
{
AppLogService.error( "Unable to load Spring context file : {} - cause : {}", fileContext, e.getMessage( ), e );
}
}
}
}
/**
* Gets the application context
*
* @return The application context
*/
public static ApplicationContext getContext( )
{
return _context;
}
/**
* Returns a list of bean among all that implements a given interface or extends a given class
*
* @param <T>
* The class type
* @param classDef
* The class type
* @return A list of beans
*/
public static <T> List<T> getBeansOfType( Class<T> classDef )
{
// Search the list in the cache
List<T> list = _mapBeansOfType.get( classDef );
if ( list != null )
{
return new ArrayList<>( list );
}
// The list is not in the cache, so we have to build it
list = new ArrayList<>( );
Map<String, T> map = _context.getBeansOfType( classDef );
String [ ] sBeanNames = map.keySet( ).toArray( new String [ map.size( )] );
for ( String strBeanName : sBeanNames )
{
String strPluginPrefix = getPrefix( strBeanName );
if ( ( strPluginPrefix == null ) || ( isEnabled( strPluginPrefix ) ) )
{
list.add( map.get( strBeanName ) );
}
}
_mapBeansOfType.put( classDef, new ArrayList<>( list ) );
return list;
}
/**
* Gets the prefix of the bean (supposed to be the plugin name)
*
* @param strBeanName
* The bean name
* @return The prefix
*/
private static String getPrefix( String strBeanName )
{
int nPos = strBeanName.indexOf( '.' );
if ( nPos > 0 )
{
return strBeanName.substring( 0, nPos );
}
return null;
}
/**
* Analyze a bean prefix to tell if it matchs an activated plugin
*
* @param strPrefix
* The prefix of a bean
* @return True if the prefix matchs an activated plugin
*/
private static boolean isEnabled( String strPrefix )
{
Plugin plugin = PluginService.getPlugin( strPrefix );
return ( plugin != null ) && plugin.isInstalled( );
}
/**
* {@inheritDoc }
*/
@Override
public void processPluginEvent( PluginEvent event )
{
// Reset cache of beansOfType if a plugin is installed or uninstalled
if ( ( event.getEventType( ) == PluginEvent.PLUGIN_INSTALLED || event.getEventType( ) == PluginEvent.PLUGIN_UNINSTALLED )
&& !_mapBeansOfType.isEmpty( ) )
{
_mapBeansOfType.clear( );
AppLogService.info( "SpringService cache cleared due to a plugin installation change - Plugin : {}", event.getPlugin( ).getName( ) );
}
}
/**
* Closes the Spring context
*
* @since 5.1.0
*/
public static void shutdown( )
{
if ( _context != null )
{
( (AbstractApplicationContext) _context ).close( );
}
}
/**
* Utils filename filter to identify context files
*/
static class ContextFileFilter implements FilenameFilter
{
/**
* Filter filename
*
* @param file
* The current file
* @param strName
* The file name
* @return true if the file is a context file otherwise false
*/
@Override
public boolean accept( File file, String strName )
{
return strName.endsWith( SUFFIX_CONTEXT_FILE );
}
}
}