org.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.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.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 ConnectionProperties connectionProperties;

    public enum PatcherType {
        db2, derby, mysql, oracle, postgres
    }

    static ConnectionPropertiesPatcher getPatcher(String _dbType) {
        PatcherType dbType = PatcherType.valueOf(_dbType);
        ConnectionPropertiesPatcher patcher = null;
        switch (dbType) {
        case db2:
            patcher = new Db2Patcher();
            break;
        case mysql:
            patcher = new MysqlPatcher();
            break;
        case oracle:
            patcher = new OraclePatcher();
            break;
        case postgres:
            patcher = new PostgresPatcher();
            break;
        case derby:
        default:
            patcher = new DerbyPatcher();
            break;
        }
        return patcher;
    }

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

        return connectionProperties;
    }

    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 void patch(File srcXml, File destXml, String host, String port, String db, String user, String pass,
            ConnectionProperties connectionProperties) throws Exception {
        this.connectionProperties = connectionProperties;
        Document doc = getDocument(srcXml);

        Attr val = getConnectionProperties(doc);
        val = patchAttribute(val, host, port, db, user, pass);

        TransformerFactory transformerFactory = TransformerFactory.newInstance();
        Transformer transformer = transformerFactory.newTransformer();
        DOMSource source = new DOMSource(doc);
        transformer.transform(source, new StreamResult(destXml));
    }

    protected Attr patchAttribute(Attr attr, String host, String port, String db, String user, String pass) {
        String[] tokens = attr.getValue().split(",");
        processBasicProperties(tokens, user, pass, connectionProperties);
        patchDb(tokens, host, port, db);
        attr.setValue(StringUtils.join(tokens, ","));
        return attr;
    }

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

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

            if (user != null) {
                patchProp(tokens, i, "Username", user);
                connectionProperties.setLogin(user);
            } else {
                prop = getPropFromPersistence(tokens, i, "Username");
                if (prop != null) {
                    connectionProperties.setLogin(prop);
                }
            }

            if (pass != null) {
                patchProp(tokens, i, "Password", pass);
                connectionProperties.setPassword(pass);
            } else {
                prop = getPropFromPersistence(tokens, i, "Password");
                if (prop != null) {
                    connectionProperties.setPassword(prop);
                }
            }
            prop = getPropFromPersistence(tokens, i, "Url");
            if (prop != null) {
                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;
    }

    private void patchDb(String[] tokens, String host, String _port, String _db) {
        for (int i = 0; i < tokens.length; ++i) {
            String prop = tokens[i].trim();
            if (prop.startsWith(URL_PREFIX)) {
                String url = getUrl(prop.substring(URL_PREFIX.length()), host, _port, _db);
                connectionProperties.setURL(url);
                tokens[i] = URL_PREFIX + url;
                break;
            }
        }
    }

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