Java tutorial
/* * Copyright (c) 2016, WSO2 Inc. (http://www.wso2.org) All Rights Reserved. * * Licensed 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.wso2.carbon.dashboard.template.deployer; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.xerces.impl.Constants; import org.w3c.dom.Attr; import org.w3c.dom.Document; import org.w3c.dom.Node; import org.w3c.dom.NodeList; import org.wso2.carbon.dashboard.template.deployer.internal.DashboardTemplateDeployerConstants; import org.wso2.carbon.dashboard.template.deployer.internal.DashboardTemplateDeployerException; import org.wso2.carbon.dashboard.template.deployer.internal.util.DashboardTemplateDeployerUtility; import org.wso2.carbon.event.template.manager.core.DeployableTemplate; import org.wso2.carbon.event.template.manager.core.TemplateDeployer; import org.wso2.carbon.event.template.manager.core.TemplateDeploymentException; import org.wso2.carbon.registry.api.Registry; import org.wso2.carbon.registry.api.RegistryException; import org.wso2.carbon.registry.api.Resource; import org.xml.sax.InputSource; import org.xml.sax.SAXException; import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import javax.xml.parsers.ParserConfigurationException; import java.io.IOException; import java.io.StringReader; import java.util.HashMap; import java.util.Map; import java.util.Properties; import java.util.Set; public class DashboardTemplateDeployer implements TemplateDeployer { private static final Log log = LogFactory.getLog(DashboardTemplateDeployer.class); @Override public String getType() { return DashboardTemplateDeployerConstants.ARTIFACT_TYPE; } @Override public void deployArtifact(DeployableTemplate template) throws TemplateDeploymentException { String artifactId = template.getArtifactId(); String content = null; Map<String, String> properties = new HashMap<>(); DocumentBuilderFactory factory = getSecuredDocumentBuilder(); try { DocumentBuilder builder = factory.newDocumentBuilder(); Document document = builder.parse(new InputSource(new StringReader(template.getArtifact()))); NodeList configNodes = document.getElementsByTagName(DashboardTemplateDeployerConstants.CONFIG_TAG); if (configNodes.getLength() > 0) { Node configNode = configNodes.item(0); // Only one node is expected if (configNode.hasChildNodes()) { // Extract the details NodeList nodeList = configNode.getChildNodes(); for (int i = 0; i < nodeList.getLength(); i++) { Node node = nodeList.item(i); if (DashboardTemplateDeployerConstants.PROPERTIES_TAG.equalsIgnoreCase(node.getNodeName()) && node.hasChildNodes()) { // Properties NodeList propertiesNodeList = node.getChildNodes(); for (int j = 0; j < propertiesNodeList.getLength(); j++) { Node propertyNode = propertiesNodeList.item(j); if (DashboardTemplateDeployerConstants.PROPERTY_TAG .equalsIgnoreCase(propertyNode.getNodeName())) { Attr attr = (Attr) propertyNode.getAttributes() .getNamedItem(DashboardTemplateDeployerConstants.NAME_ATTRIBUTE); properties.put(attr.getValue(), propertyNode.getFirstChild().getNodeValue().trim()); } } } else if (DashboardTemplateDeployerConstants.CONTENT_TAG .equalsIgnoreCase(node.getNodeName())) { content = node.getFirstChild().getNodeValue(); } } } } } catch (ParserConfigurationException e) { throw new DashboardTemplateDeployerException("Error in creating XML document builder.", e); } catch (SAXException e) { throw new DashboardTemplateDeployerException("Error in parsing XML content of: " + artifactId, e); } catch (IOException e) { throw new DashboardTemplateDeployerException("Error in loading XML content of: " + artifactId, e); } if (content == null || content.trim().isEmpty()) { throw new DashboardTemplateDeployerException("Empty dashboard content for artifact: " + artifactId); } // Store the directory name for the artifact id Registry registry = DashboardTemplateDeployerUtility.getRegistry(); try { Resource resource; if (registry.resourceExists(DashboardTemplateDeployerConstants.ARTIFACT_DASHBOARD_ID_MAPPING_PATH)) { // If same gadgets for same artifact exist, remove them first resource = registry.get(DashboardTemplateDeployerConstants.ARTIFACT_DASHBOARD_ID_MAPPING_PATH); // Delete this artifact if exists if (resource.getProperty(artifactId) != null) { undeployArtifact(artifactId); } } else { resource = registry.newResource(); } resource.setProperty(artifactId, properties.get(DashboardTemplateDeployerConstants.DASHBOARD_ID)); // Save the resource registry.put(DashboardTemplateDeployerConstants.ARTIFACT_DASHBOARD_ID_MAPPING_PATH, resource); } catch (RegistryException e) { throw new DashboardTemplateDeployerException("Failed to access resource at: " + DashboardTemplateDeployerConstants.ARTIFACT_DASHBOARD_ID_MAPPING_PATH + " in registry", e); } try { Resource resource = registry.newResource(); resource.setContent(content); resource.setMediaType("application/json"); registry.put(DashboardTemplateDeployerConstants.DASHBOARDS_RESOURCE_PATH + properties.get(DashboardTemplateDeployerConstants.DASHBOARD_ID), resource); log.info("Dashboard definition of [" + artifactId + "] has been created."); } catch (RegistryException e) { throw new DashboardTemplateDeployerException("Failed to access resource at: " + DashboardTemplateDeployerConstants.ARTIFACT_DASHBOARD_ID_MAPPING_PATH + " in registry", e); } } @Override public void undeployArtifact(String artifactId) throws TemplateDeploymentException { Registry registry = DashboardTemplateDeployerUtility.getRegistry(); try { if (registry.resourceExists(DashboardTemplateDeployerConstants.ARTIFACT_DASHBOARD_ID_MAPPING_PATH)) { Resource resource = registry .get(DashboardTemplateDeployerConstants.ARTIFACT_DASHBOARD_ID_MAPPING_PATH); String dashboardId = resource.getProperty(artifactId); if (dashboardId != null) { // Remove the artifact entry from registry resource.removeProperty(artifactId); boolean isSharedDashboardId = false; // Check whether other artifacts use the same gadget. If so, don't delete the folder. Properties properties = resource.getProperties(); Set<Object> keys = properties.keySet(); for (Object key : keys) { String id = resource.getProperty(key.toString()); if (dashboardId.equals(id)) { // Same gadget is used by other artifacts too isSharedDashboardId = true; break; } } if (!isSharedDashboardId) { String path = DashboardTemplateDeployerConstants.DASHBOARDS_RESOURCE_PATH + dashboardId; try { if (registry.resourceExists(path)) { registry.delete(path); log.info("Dashboard definition of [" + artifactId + "] has been undeployed."); } else { log.warn("Dashboard definition of [" + artifactId + "] does not exist at " + path); } } catch (RegistryException e) { throw new DashboardTemplateDeployerException(e.getMessage(), e); } } registry.put(DashboardTemplateDeployerConstants.ARTIFACT_DASHBOARD_ID_MAPPING_PATH, resource); log.info("Undeployed successfully gadget: " + artifactId); } else { // Does not exist log.warn("Artifact: " + artifactId + " does not exist to undeploy"); } } else { // Does not exist log.warn("Artifact: " + artifactId + " does not exist to undeploy"); } } catch (RegistryException e) { throw new DashboardTemplateDeployerException("Failed to access resource at: " + DashboardTemplateDeployerConstants.ARTIFACT_DASHBOARD_ID_MAPPING_PATH + " from registry", e); } } @Override public void deployIfNotDoneAlready(DeployableTemplate template) throws TemplateDeploymentException { Registry registry = DashboardTemplateDeployerUtility.getRegistry(); try { if (registry.resourceExists(DashboardTemplateDeployerConstants.ARTIFACT_DASHBOARD_ID_MAPPING_PATH)) { // If same gadgets for same artifact exist, remove them first Resource resource = registry .get(DashboardTemplateDeployerConstants.ARTIFACT_DASHBOARD_ID_MAPPING_PATH); if (resource.getProperty(template.getArtifactId()) == null) { deployArtifact(template); } } else { deployArtifact(template); } } catch (RegistryException e) { throw new DashboardTemplateDeployerException("Failed to access resource at: " + DashboardTemplateDeployerConstants.ARTIFACT_DASHBOARD_ID_MAPPING_PATH + " from registry", e); } } private static DocumentBuilderFactory getSecuredDocumentBuilder() { DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance(); dbf.setNamespaceAware(true); dbf.setXIncludeAware(false); dbf.setExpandEntityReferences(false); try { dbf.setFeature(Constants.SAX_FEATURE_PREFIX + Constants.EXTERNAL_GENERAL_ENTITIES_FEATURE, false); dbf.setFeature(Constants.SAX_FEATURE_PREFIX + Constants.EXTERNAL_PARAMETER_ENTITIES_FEATURE, false); dbf.setFeature(Constants.XERCES_FEATURE_PREFIX + Constants.LOAD_EXTERNAL_DTD_FEATURE, false); } catch (ParserConfigurationException e) { log.error("Failed to load XML Processor Feature " + Constants.EXTERNAL_GENERAL_ENTITIES_FEATURE + " or " + Constants.EXTERNAL_PARAMETER_ENTITIES_FEATURE + " or " + Constants.LOAD_EXTERNAL_DTD_FEATURE); } org.apache.xerces.util.SecurityManager securityManager = new org.apache.xerces.util.SecurityManager(); securityManager.setEntityExpansionLimit(DashboardTemplateDeployerConstants.ENTITY_EXPANSION_LIMIT); dbf.setAttribute(Constants.XERCES_PROPERTY_PREFIX + Constants.SECURITY_MANAGER_PROPERTY, securityManager); return dbf; } }