franta-hg@43: /**
franta-hg@43:  * Alt2XML
franta-hg@43:  * Copyright © 2014 František Kučera (frantovo.cz)
franta-hg@43:  *
franta-hg@43:  * This program is free software: you can redistribute it and/or modify
franta-hg@43:  * it under the terms of the GNU General Public License as published by
franta-hg@43:  * the Free Software Foundation, either version 3 of the License, or
franta-hg@43:  * (at your option) any later version.
franta-hg@43:  *
franta-hg@43:  * This program is distributed in the hope that it will be useful,
franta-hg@43:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
franta-hg@43:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
franta-hg@43:  * GNU General Public License for more details.
franta-hg@43:  *
franta-hg@43:  * You should have received a copy of the GNU General Public License
franta-hg@43:  * along with this program. If not, see <http://www.gnu.org/licenses/>.
franta-hg@43:  */
franta-hg@49: package cz.frantovo.alt2xml.out.xpath;
franta-hg@43: 
franta-hg@63: import cz.frantovo.alt2xml.out.AbstractDOMAction;
franta-hg@43: import cz.frantovo.alt2xml.out.ActionContext;
franta-hg@49: import cz.frantovo.alt2xml.out.OutputActionException;
franta-hg@63: import java.io.PrintWriter;
franta-hg@72: import java.util.Arrays;
franta-hg@69: import java.util.HashMap;
franta-hg@69: import java.util.List;
franta-hg@69: import java.util.Map;
franta-hg@63: import javax.xml.transform.dom.DOMResult;
franta-hg@63: import javax.xml.xpath.XPath;
franta-hg@63: import javax.xml.xpath.XPathExpression;
franta-hg@63: import javax.xml.xpath.XPathExpressionException;
franta-hg@63: import javax.xml.xpath.XPathFactory;
franta-hg@97: import javax.xml.xpath.XPathVariableResolver;
franta-hg@101: import org.w3c.dom.Node;
franta-hg@43: 
franta-hg@43: /**
franta-hg@43:  *
franta-hg@43:  * @author Ing. František Kučera (frantovo.cz)
franta-hg@43:  */
franta-hg@63: public class XPathAction extends AbstractDOMAction {
franta-hg@43: 
franta-hg@69: 	public static final String PARAMETER_TYPED_PARAMETERS = "typed-parameters";
franta-hg@79: 	public static final String PARAMETER_LINE_BREAK = "line-break";
franta-hg@97: 	public static final String PARAMETER_ENVIRONMENT_VARIABLES = "environment-variables";
franta-hg@79: 	private final boolean typedParameters;
franta-hg@79: 	private final boolean lineBreak;
franta-hg@97: 	private final boolean environmentVariables;
franta-hg@66: 	private final XPathFactory xpathFactory;
franta-hg@66: 	private final XPath xpath;
franta-hg@68: 	private final String expressionString;
franta-hg@66: 
franta-hg@68: 	public XPathAction(ActionContext actionContext) throws OutputActionException {
franta-hg@43: 		super(actionContext);
franta-hg@66: 		xpathFactory = XPathFactory.newInstance();
franta-hg@66: 		xpath = xpathFactory.newXPath();
franta-hg@43: 
franta-hg@69: 		final List<String> actionData = getActionContext().getActionData();
franta-hg@63: 
franta-hg@69: 		if (actionData.size() < 1) {
franta-hg@69: 			throw new OutputActionException("Please specify the XPath expression as action data");
franta-hg@69: 		} else {
franta-hg@69: 
franta-hg@79: 			typedParameters = Boolean.parseBoolean(actionContext.getActionProperties().getProperty(PARAMETER_TYPED_PARAMETERS));
franta-hg@79: 			lineBreak = Boolean.parseBoolean(actionContext.getActionProperties().getProperty(PARAMETER_LINE_BREAK, Boolean.TRUE.toString()));
franta-hg@97: 			environmentVariables = Boolean.parseBoolean(actionContext.getActionProperties().getProperty(PARAMETER_ENVIRONMENT_VARIABLES, Boolean.FALSE.toString()));
franta-hg@69: 
franta-hg@69: 			Map<String, Object> xpathParameters = new HashMap<>();
franta-hg@69: 
franta-hg@69: 			for (int i = 1; i < actionData.size(); i++) {
franta-hg@69: 				String parameterName = actionData.get(i++);
franta-hg@72: 				String parameterType = typedParameters ? actionData.get(i++) : PARAMETER_TYPE.STRING.name();
franta-hg@71: 				Object parameterValue = parseParameterValue(parameterType, actionData.get(i));
franta-hg@69: 				xpathParameters.put(parameterName, parameterValue);
franta-hg@69: 			}
franta-hg@69: 
franta-hg@97: 			XPathVariableResolver cliVariableResolver = new PropertiesVariableResolver(xpathParameters);
franta-hg@97: 			XPathVariableResolver variableResolver = environmentVariables ? new CompoundVariableResolver(cliVariableResolver, new EnvironmentVariableResolver()) : cliVariableResolver;
franta-hg@97: 
franta-hg@97: 			xpath.setXPathVariableResolver(variableResolver);
franta-hg@69: 
franta-hg@69: 			expressionString = actionData.get(0);
franta-hg@63: 		}
franta-hg@43: 	}
franta-hg@68: 
franta-hg@72: 	private enum PARAMETER_TYPE {
franta-hg@72: 
franta-hg@72: 		// TODO: wait for Java 8 widespread and rewrite with lambdas :-)
franta-hg@72: 		STRING {
franta-hg@72: 					@Override
franta-hg@72: 					public Object parse(String value) {
franta-hg@72: 						return value;
franta-hg@72: 					}
franta-hg@72: 				},
franta-hg@72: 		BOOLEAN {
franta-hg@72: 					@Override
franta-hg@72: 					public Object parse(String value) {
franta-hg@72: 						return Boolean.valueOf(value);
franta-hg@72: 					}
franta-hg@72: 				},
franta-hg@72: 		INTEGER {
franta-hg@72: 					@Override
franta-hg@72: 					public Object parse(String value) {
franta-hg@72: 						return Integer.parseInt(value);
franta-hg@72: 					}
franta-hg@72: 				},
franta-hg@72: 		LONG {
franta-hg@72: 					@Override
franta-hg@72: 					public Object parse(String value) {
franta-hg@72: 						return Long.parseLong(value);
franta-hg@72: 					}
franta-hg@72: 				},
franta-hg@72: 		DOUBLE {
franta-hg@72: 					@Override
franta-hg@72: 					public Object parse(String value) {
franta-hg@72: 						return Double.parseDouble(value);
franta-hg@72: 					}
franta-hg@72: 				};
franta-hg@72: 
franta-hg@72: 		public abstract Object parse(String value);
franta-hg@72: 
franta-hg@72: 	}
franta-hg@72: 
franta-hg@72: 	private static Object parseParameterValue(String type, String value) throws OutputActionException {
franta-hg@72: 
franta-hg@72: 		try {
franta-hg@72: 			PARAMETER_TYPE parameterType = PARAMETER_TYPE.valueOf(type.toUpperCase());
franta-hg@72: 
franta-hg@72: 			try {
franta-hg@72: 				return parameterType.parse(value);
franta-hg@72: 			} catch (IllegalArgumentException e) {
franta-hg@72: 				throw new OutputActionException("Unable to parse value: „" + value + "“ as " + parameterType.name());
franta-hg@72: 			}
franta-hg@72: 		} catch (IllegalArgumentException e) {
franta-hg@72: 			throw new OutputActionException(
franta-hg@72: 					"Invalid XPath parameter type: „" + type
franta-hg@72: 					+ "“. Possible values are: " + Arrays.toString(PARAMETER_TYPE.values())
franta-hg@72: 					+ " and are case insensitive.",
franta-hg@72: 					e);
franta-hg@72: 		}
franta-hg@69: 	}
franta-hg@69: 
franta-hg@68: 	@Override
franta-hg@68: 	public void run(DOMResult domResult) throws OutputActionException {
franta-hg@101: 		XPathExpression xpathExpression = null;
franta-hg@68: 		try {
franta-hg@101: 			Node document = domResult.getNode();
franta-hg@101: 
franta-hg@101: 			xpath.setNamespaceContext(new DocumentNamespaceContext(document));
franta-hg@101: 
franta-hg@101: 			try {
franta-hg@101: 				xpathExpression = xpath.compile(expressionString);
franta-hg@101: 			} catch (XPathExpressionException e) {
franta-hg@101: 				throw new OutputActionException("Unable to compile XPath: " + expressionString, e);
franta-hg@101: 			}
franta-hg@101: 
franta-hg@101: 			String result = xpathExpression.evaluate(document);
franta-hg@68: 			try (PrintWriter out = new PrintWriter(getActionContext().getOutputStream())) {
franta-hg@79: 				out.print(result);
franta-hg@79: 				if (lineBreak) {
franta-hg@79: 					out.println();
franta-hg@79: 				}
franta-hg@68: 			}
franta-hg@68: 		} catch (XPathExpressionException e) {
franta-hg@68: 			throw new OutputActionException("Unable to evaluate XPath: " + xpathExpression, e);
franta-hg@68: 		}
franta-hg@68: 	}
franta-hg@43: }