Mercurial > dive4elements > river
view flys-artifacts/src/main/java/de/intevation/flys/artifacts/datacage/Recommendations.java @ 5779:ebec12def170
Datacage: Add a pool of builders to make it multi threadable.
XML DOM is not thread safe. Therefore the old implementation only allowed one thread
to use the builder at a time. As the complexity of the configuration
has increased over time this has become a bottleneck of the whole application
because it took quiet some time to build a result. Furthermore the builder code path
is visited very frequent. So many concurrent requests were piled up
resulting in long waits for the users.
To mitigate this problem a round robin pool of builders is used now.
Each of the pooled builders has an independent copy of the XML template
and can be run in parallel.
The number of builders is determined by the system property
'flys.datacage.pool.size'. It defaults to 4.
author | Sascha L. Teichmann <teichmann@intevation.de> |
---|---|
date | Sun, 21 Apr 2013 12:48:09 +0200 |
parents | cf4cc385e7c6 |
children |
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package de.intevation.flys.artifacts.datacage; import java.util.Map; import java.util.HashMap; import java.util.List; import java.util.ArrayList; import java.io.InputStream; import java.io.IOException; import java.io.File; import java.io.FileInputStream; import java.sql.Connection; import java.sql.SQLException; import org.apache.log4j.Logger; import org.w3c.dom.Document; import org.w3c.dom.Node; import org.hibernate.Session; import org.hibernate.SessionFactory; import org.hibernate.jdbc.Work; import de.intevation.artifacts.common.utils.Config; import de.intevation.artifacts.common.utils.XMLUtils; import de.intevation.artifacts.common.utils.StringUtils; import de.intevation.flys.artifacts.FLYSArtifact; import de.intevation.flys.backend.SessionFactoryProvider; import de.intevation.flys.backend.SessionHolder; import de.intevation.artifactdatabase.data.StateData; import de.intevation.flys.artifacts.datacage.templating.Builder; import de.intevation.flys.artifacts.datacage.templating.BuilderPool; /** * Also accessible as Singleton with getInstance(). */ public class Recommendations { public static final String CONNECTION_USER = "user"; public static final String CONNECTION_SYSTEM = "system"; public static final String CONNECTION_SEDDB = "seddb"; public static final String DEFAULT_CONNECTION_NAME = CONNECTION_SYSTEM; private static Logger log = Logger.getLogger(Recommendations.class); private static final boolean DEVELOPMENT_MODE = Boolean.getBoolean("flys.datacage.recommendations.development"); public static final String XPATH_TEMPLATE = "/artifact-database/metadata/template/text()"; public static final String DEFAULT_TEMPLATE_PATH = "${artifacts.config.dir}/meta-data.xml"; private static Recommendations INSTANCE; public static class BuilderPoolProvider { protected BuilderPool builderPool; public BuilderPoolProvider() { } public BuilderPoolProvider(BuilderPool builderPool) { this.builderPool = builderPool; } public BuilderPool getBuilderPool() { return builderPool; } } // class BuilderProvider public static class FileBuilderPoolProvider extends BuilderPoolProvider { protected File file; protected long lastModified; public FileBuilderPoolProvider() { } public FileBuilderPoolProvider(File file) { this.file = file; lastModified = Long.MIN_VALUE; } @Override public synchronized BuilderPool getBuilderPool() { long modified = file.lastModified(); if (modified > lastModified) { lastModified = modified; try { Document template = loadTemplate(file); builderPool = new BuilderPool(template); } catch (IOException ioe) { log.error(ioe); } } return builderPool; } public BuilderPoolProvider toStaticProvider() { return new BuilderPoolProvider(builderPool); } } // class BuilderProvider protected BuilderPoolProvider builderPoolProvider; public Recommendations() { } public Recommendations(BuilderPoolProvider builderPoolProvider) { this.builderPoolProvider = builderPoolProvider; } public BuilderPool getBuilderPool() { return builderPoolProvider.getBuilderPool(); } protected static void artifactToParameters( FLYSArtifact artifact, Map<String, Object> parameters ) { parameters.put("CURRENT-STATE-ID", artifact.getCurrentStateId()); parameters.put("ARTIFACT-ID", artifact.identifier()); for (StateData sd: artifact.getAllData()) { Object value = sd.getValue(); if (value == null) { continue; } String key = sd.getName().replace('.', '-').toUpperCase(); parameters.put(key, value); } } /** * Put Key/Values from \param src to \param dst, but uppercase * both Keys and Values. */ public static void convertKeysToUpperCase( Map<String, Object> src, Map<String, Object> dst ) { for (Map.Entry<String, Object> entry: src.entrySet()) { dst.put(entry.getKey().toUpperCase(), entry.getValue()); } } /** * Append recommendations to \param result. * @param extraParameters parameters (typicall example: 'recommended') */ public void recommend( FLYSArtifact artifact, String userId, String [] outs, Map<String, Object> extraParameters, Node result ) { Map<String, Object> parameters = new HashMap<String, Object>(); if (extraParameters != null) { convertKeysToUpperCase(extraParameters, parameters); } if (userId != null) { parameters.put("USER-ID", userId); } if (artifact != null) { artifactToParameters(artifact, parameters); } parameters.put("ARTIFACT-OUTS", StringUtils.toUpperCase(outs)); parameters.put("PARAMETERS", parameters); recommend(parameters, userId, result); } /** * Append recommendations to \param result. */ public void recommend( Map<String, Object> parameters, String userId, Node result ) { recommend(parameters, userId, result, SessionHolder.HOLDER.get()); } public void recommend( final Map<String, Object> parameters, final String userId, final Node result, Session systemSession ) { systemSession.doWork(new Work() { @Override public void execute(final Connection systemConnection) throws SQLException { SessionFactory sedDBFactory = SessionFactoryProvider.getSedDBSessionFactory(); Session sedDBSession = sedDBFactory.openSession(); try { sedDBSession.doWork(new Work() { @Override public void execute(Connection sedDBConnection) throws SQLException { recommend( parameters, userId, result, systemConnection, sedDBConnection); } }); } finally { sedDBSession.close(); } } }); } public void recommend( Map<String, Object> parameters, String userId, Node result, Connection systemConnection, Connection seddbConnection ) throws SQLException { List<Builder.NamedConnection> connections = new ArrayList<Builder.NamedConnection>(3); Connection userConnection = userId != null ? DBConfig .getInstance() .getDBConnection() .getDataSource() .getConnection() : null; try { connections.add(new Builder.NamedConnection( CONNECTION_SYSTEM, systemConnection, true)); if (seddbConnection != null) { connections.add(new Builder.NamedConnection( CONNECTION_SEDDB, seddbConnection, true)); } if (userConnection != null) { connections.add(new Builder.NamedConnection( CONNECTION_USER, userConnection, false)); } getBuilderPool().build(connections, result, parameters); } finally { if (userConnection != null) { userConnection.close(); } } } /** Get singleton instance. */ public static synchronized Recommendations getInstance() { if (INSTANCE == null) { INSTANCE = createRecommendations(); } return INSTANCE; } protected static Document loadTemplate(File file) throws IOException { InputStream in = new FileInputStream(file); try { Document template = XMLUtils.parseDocument(in); if (template == null) { throw new IOException("cannot load template"); } return template; } finally { in.close(); } } public static Recommendations createRecommendations(File file) { log.debug("Recommendations.createBuilder"); if (!file.isFile() || !file.canRead()) { log.error("Cannot open template file '" + file + "'"); return null; } FileBuilderPoolProvider fbp = new FileBuilderPoolProvider(file); if (fbp.getBuilderPool() == null) { log.error("failed loading builder"); return null; } BuilderPoolProvider bp = DEVELOPMENT_MODE ? fbp : fbp.toStaticProvider(); return new Recommendations(bp); } protected static Recommendations createRecommendations() { log.debug("Recommendations.createRecommendations"); String path = Config.getStringXPath(XPATH_TEMPLATE); if (path == null) { path = DEFAULT_TEMPLATE_PATH; } path = Config.replaceConfigDir(path); log.info("Meta data template: " + path); return createRecommendations(new File(path)); } } // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf-8 :