org.apache.openmeetings.cli.ConnectionPropertiesPatcher.java Source code

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/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License") +  you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.openmeetings.cli;

import java.io.File;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpression;
import javax.xml.xpath.XPathFactory;

import org.apache.commons.lang3.StringEscapeUtils;
import org.apache.commons.lang3.StringUtils;
import org.apache.openmeetings.util.ConnectionProperties.DbType;
import org.apache.openmeetings.util.ConnectionProperties;
import org.apache.openmeetings.util.OmFileHelper;
import org.w3c.dom.Attr;
import org.w3c.dom.Document;
import org.w3c.dom.Element;

public abstract class ConnectionPropertiesPatcher {
    protected static final String URL_PREFIX = "Url";
    protected static final String DRIVER_PREFIX = "DriverClassName";
    protected static final String USER_PREFIX = "Username";
    protected static final String PASS_PREFIX = "Password";
    protected ConnectionProperties props;

    public static ConnectionPropertiesPatcher getPatcher(ConnectionProperties props) {
        ConnectionPropertiesPatcher patcher = null;
        switch (props.getDbType()) {
        case db2:
            patcher = new Db2Patcher();
            break;
        case mssql:
            patcher = new MssqlPatcher();
            break;
        case mysql:
            patcher = new MysqlPatcher();
            break;
        case oracle:
            patcher = new OraclePatcher();
            break;
        case postgresql:
            patcher = new PostgresPatcher();
            break;
        case derby:
        default:
            patcher = new DerbyPatcher();
            break;
        }
        patcher.props = props;
        return patcher;
    }

    public static ConnectionProperties getConnectionProperties(File conf) throws Exception {
        ConnectionProperties props = new ConnectionProperties();
        Document doc = getDocument(conf);
        Attr attr = getConnectionProperties(doc);
        String[] tokens = attr.getValue().split(",");
        loadProperties(tokens, props);

        return props;
    }

    private static Document getDocument(File xml) throws Exception {
        DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
        //dbFactory.setNamespaceAware(true);
        DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
        return dBuilder.parse(xml);
    }

    private static Attr getConnectionProperties(Document doc) throws Exception {
        XPath xPath = XPathFactory.newInstance().newXPath();
        XPathExpression expr = xPath
                .compile("/persistence/persistence-unit/properties/property[@name='openjpa.ConnectionProperties']");

        Element element = (Element) expr.evaluate(doc, XPathConstants.NODE);
        return element.getAttributeNode("value");
    }

    public static void patch(ConnectionProperties props) throws Exception {
        ConnectionPropertiesPatcher patcher = getPatcher(props);
        Document doc = getDocument(OmFileHelper.getPersistence(props.getDbType()));
        Attr attr = getConnectionProperties(doc);
        String[] tokens = attr.getValue().split(",");
        patcher.patchAttribute(tokens);
        attr.setValue(StringUtils.join(tokens, ","));

        TransformerFactory transformerFactory = TransformerFactory.newInstance();
        Transformer transformer = transformerFactory.newTransformer();
        DOMSource source = new DOMSource(doc);
        transformer.transform(source, new StreamResult(OmFileHelper.getPersistence().getCanonicalPath())); //this constructor is used to avoid transforming path to URI
    }

    public static ConnectionProperties patch(String dbType, String host, String port, String db, String user,
            String pass) throws Exception {
        ConnectionProperties props = getConnectionProperties(OmFileHelper.getPersistence(dbType));
        props.setLogin(user);
        props.setPassword(pass);
        ConnectionPropertiesPatcher patcher = getPatcher(props);
        props.setURL(patcher.getUrl(props.getURL(), host, port, db));
        patch(props);
        return props;
    }

    public static void updateUrl(ConnectionProperties props, String host, String port, String db) {
        ConnectionPropertiesPatcher patcher = getPatcher(props);
        props.setURL(patcher.getUrl(props.getURL(), host, port, db));
    }

    protected void patchAttribute(String[] tokens) {
        for (int i = 0; i < tokens.length; ++i) {
            patchProp(tokens, i, USER_PREFIX, props.getLogin());
            patchProp(tokens, i, PASS_PREFIX, props.getPassword() == null ? "" : props.getPassword());
            patchProp(tokens, i, URL_PREFIX, props.getURL());
        }
    }

    protected static void patchProp(String[] tokens, int idx, String name, String value) {
        String prop = tokens[idx].trim();
        if (prop.startsWith(name)) {
            prop = name + "=" + StringEscapeUtils.escapeXml10(value);
            tokens[idx] = prop;
        }
    }

    private static void loadProperties(String[] tokens, ConnectionProperties connectionProperties) {
        String prop;
        for (int i = 0; i < tokens.length; ++i) {
            prop = getPropFromPersistence(tokens, i, DRIVER_PREFIX);
            if (prop != null) {
                connectionProperties.setDriver(prop);
            }

            prop = getPropFromPersistence(tokens, i, USER_PREFIX);
            if (prop != null) {
                connectionProperties.setLogin(prop);
            }

            prop = getPropFromPersistence(tokens, i, PASS_PREFIX);
            if (prop != null) {
                connectionProperties.setPassword(prop);
            }

            prop = getPropFromPersistence(tokens, i, URL_PREFIX);
            if (prop != null) {
                try {
                    //will try to "guess" dbType
                    String[] parts = prop.split(":");
                    connectionProperties
                            .setDbType("sqlserver".equals(parts[1]) ? DbType.mssql : DbType.valueOf(parts[1]));
                } catch (Exception e) {
                    //ignore
                }
                connectionProperties.setURL(prop);
            }
        }
    }

    protected static String getPropFromPersistence(String[] tokens, int idx, String name) {
        String prop = tokens[idx].trim();
        if (prop.startsWith(name)) {
            //From "Username=root" getting only "root"
            return prop.substring(prop.indexOf("=") + 1);
        }
        return null;
    }

    protected abstract String getUrl(String url, String host, String port, String db);
}