diff -r 822b7e3d064d -r b3f14cd4f3ab src/main/java/de/uapcore/lightpit/DatabaseFacade.java
--- a/src/main/java/de/uapcore/lightpit/DatabaseFacade.java	Fri Oct 23 20:34:57 2020 +0200
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,176 +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 org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-import javax.naming.Context;
-import javax.naming.InitialContext;
-import javax.naming.NamingException;
-import javax.servlet.ServletContext;
-import javax.servlet.ServletContextEvent;
-import javax.servlet.ServletContextListener;
-import javax.servlet.annotation.WebListener;
-import javax.sql.DataSource;
-import java.sql.Connection;
-import java.sql.DatabaseMetaData;
-import java.sql.SQLException;
-import java.util.Optional;
-
-/**
- * Provides access to different privilege layers within the database.
- */
-@WebListener
-public final class DatabaseFacade implements ServletContextListener {
-
-    private static final Logger LOG = LoggerFactory.getLogger(DatabaseFacade.class);
-
-    /**
-     * Timeout in seconds for the validation test.
-     */
-    private static final int DB_TEST_TIMEOUT = 10;
-
-    /**
-     * Specifies the database dialect.
-     */
-    public enum Dialect {
-        Postgres
-    }
-
-    /**
-     * The database dialect to use.
-     * <p>
-     * May be overridden by context parameter.
-     *
-     * @see Constants#CTX_ATTR_DB_DIALECT
-     */
-    private Dialect dialect = Dialect.Postgres;
-
-    /**
-     * The default schema to test against when validating the connection.
-     * <p>
-     * May be overridden by context parameter.
-     *
-     * @see Constants#CTX_ATTR_DB_SCHEMA
-     */
-    private static final String DB_DEFAULT_SCHEMA = "lightpit";
-
-    /**
-     * The attribute name in the Servlet context under which an instance of this class can be found.
-     */
-    public static final String SC_ATTR_NAME = DatabaseFacade.class.getName();
-
-    private static final String DS_JNDI_NAME = "jdbc/lightpit/app";
-    private DataSource dataSource;
-
-    /**
-     * Returns the data source.
-     *
-     * @return a data source
-     */
-    public DataSource getDataSource() {
-        return dataSource;
-    }
-
-    public Dialect getSQLDialect() {
-        return dialect;
-    }
-
-    private static void checkConnection(DataSource ds, String testSchema) {
-        try (Connection conn = ds.getConnection()) {
-            if (!conn.isValid(DB_TEST_TIMEOUT)) {
-                throw new SQLException("Validation check failed.");
-            }
-            if (conn.isReadOnly()) {
-                throw new SQLException("Connection is read-only and thus unusable.");
-            }
-            if (!conn.getSchema().equals(testSchema)) {
-                throw new SQLException(String.format("Connection is not configured to use the schema %s.", testSchema));
-            }
-            DatabaseMetaData metaData = conn.getMetaData();
-            LOG.info("Connections as {} to {}/{} ready to go.", metaData.getUserName(), metaData.getURL(), conn.getSchema());
-        } catch (SQLException ex) {
-            LOG.error("Checking database connection failed", ex);
-        }
-    }
-
-    private static DataSource retrieveDataSource(Context ctx) {
-        DataSource ret = null;
-        try {
-            ret = (DataSource) ctx.lookup(DS_JNDI_NAME);
-            LOG.info("Data source retrieved.");
-        } catch (NamingException ex) {
-            LOG.error("Data source {} not available.", DS_JNDI_NAME);
-            LOG.error("Reason for the missing data source: ", ex);
-        }
-        return ret;
-    }
-
-    @Override
-    public void contextInitialized(ServletContextEvent sce) {
-        ServletContext sc = sce.getServletContext();
-
-        dataSource = null;
-
-        final String dbSchema = Optional
-                .ofNullable(sc.getInitParameter(Constants.CTX_ATTR_DB_SCHEMA))
-                .orElse(DB_DEFAULT_SCHEMA);
-        final String dbDialect = sc.getInitParameter(Constants.CTX_ATTR_DB_DIALECT);
-        if (dbDialect != null) {
-            try {
-                dialect = Dialect.valueOf(dbDialect);
-            } catch (IllegalArgumentException ex) {
-                LOG.error("Unknown or unsupported database dialect {}. Defaulting to {}.", dbDialect, dialect);
-            }
-        }
-
-        try {
-            LOG.debug("Trying to access JNDI context ...");
-            Context initialCtx = new InitialContext();
-            Context ctx = (Context) initialCtx.lookup("java:comp/env");
-
-            dataSource = retrieveDataSource(ctx);
-
-            if (dataSource != null) {
-                checkConnection(dataSource, dbSchema);
-            }
-        } catch (NamingException | ClassCastException ex) {
-            LOG.error("Cannot access JNDI resources.", ex);
-        }
-
-        sc.setAttribute(SC_ATTR_NAME, this);
-        LOG.info("Database facade injected into ServletContext.");
-    }
-
-    @Override
-    public void contextDestroyed(ServletContextEvent sce) {
-        dataSource = null;
-    }
-}