/* * Copyright 2017 Anton Tananaev (anton@traccar.org) * Copyright 2017 Andrey Kunitsyn (andrey@traccar.org) * * 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.traccar.processing; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.Method; import java.util.Arrays; import java.util.Collection; import java.util.Collections; import java.util.HashSet; import java.util.Map; import java.util.Set; import io.netty.channel.ChannelHandler; import org.apache.commons.jexl2.JexlEngine; import org.apache.commons.jexl2.JexlException; import org.apache.commons.jexl2.MapContext; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.traccar.BaseDataHandler; import org.traccar.Context; import org.traccar.model.Attribute; import org.traccar.model.Device; import org.traccar.model.Position; @ChannelHandler.Sharable public class ComputedAttributesHandler extends BaseDataHandler { private static final Logger LOGGER = LoggerFactory.getLogger(ComputedAttributesHandler.class); private JexlEngine engine; private boolean mapDeviceAttributes; public ComputedAttributesHandler() { engine = new JexlEngine(); engine.setStrict(true); engine.setFunctions(Collections.singletonMap("math", (Object) Math.class)); if (Context.getConfig() != null) { mapDeviceAttributes = Context.getConfig().getBoolean("processing.computedAttributes.deviceAttributes"); } } private MapContext prepareContext(Position position) { MapContext result = new MapContext(); if (mapDeviceAttributes) { Device device = Context.getIdentityManager().getById(position.getDeviceId()); if (device != null) { for (Object key : device.getAttributes().keySet()) { result.set((String) key, device.getAttributes().get(key)); } } } Set<Method> methods = new HashSet<>(Arrays.asList(position.getClass().getMethods())); methods.removeAll(Arrays.asList(Object.class.getMethods())); for (Method method : methods) { if (method.getName().startsWith("get") && method.getParameterTypes().length == 0) { String name = Character.toLowerCase(method.getName().charAt(3)) + method.getName().substring(4); try { if (!method.getReturnType().equals(Map.class)) { result.set(name, method.invoke(position)); } else { for (Object key : ((Map) method.invoke(position)).keySet()) { result.set((String) key, ((Map) method.invoke(position)).get(key)); } } } catch (IllegalAccessException | InvocationTargetException error) { LOGGER.warn("Attribute reflection error", error); } } } return result; } public Object computeAttribute(Attribute attribute, Position position) throws JexlException { return engine.createExpression(attribute.getExpression()).evaluate(prepareContext(position)); } @Override protected Position handlePosition(Position position) { Collection<Attribute> attributes = Context.getAttributesManager().getItems( Context.getAttributesManager().getAllDeviceItems(position.getDeviceId())); for (Attribute attribute : attributes) { if (attribute.getAttribute() != null) { Object result = null; try { result = computeAttribute(attribute, position); } catch (JexlException error) { LOGGER.warn("Attribute computation error", error); } if (result != null) { try { switch (attribute.getType()) { case "number": Number numberValue = (Number) result; position.getAttributes().put(attribute.getAttribute(), numberValue); break; case "boolean": Boolean booleanValue = (Boolean) result; position.getAttributes().put(attribute.getAttribute(), booleanValue); break; default: position.getAttributes().put(attribute.getAttribute(), result.toString()); } } catch (ClassCastException error) { LOGGER.warn("Attribute cast error", error); } } } } return position; } }