Java tutorial
/** * Copyright 2016-2018 The Thingsboard Authors * * 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.thingsboard.server.service.script; import com.google.common.util.concurrent.Futures; import com.google.common.util.concurrent.ListenableFuture; import lombok.extern.slf4j.Slf4j; import java.util.Map; import java.util.UUID; import java.util.concurrent.ConcurrentHashMap; import java.util.concurrent.atomic.AtomicInteger; /** * Created by ashvayka on 26.09.18. */ @Slf4j public abstract class AbstractJsInvokeService implements JsInvokeService { protected Map<UUID, String> scriptIdToNameMap = new ConcurrentHashMap<>(); protected Map<UUID, AtomicInteger> blackListedFunctions = new ConcurrentHashMap<>(); @Override public ListenableFuture<UUID> eval(JsScriptType scriptType, String scriptBody, String... argNames) { UUID scriptId = UUID.randomUUID(); String functionName = "invokeInternal_" + scriptId.toString().replace('-', '_'); String jsScript = generateJsScript(scriptType, functionName, scriptBody, argNames); return doEval(scriptId, functionName, jsScript); } @Override public ListenableFuture<Object> invokeFunction(UUID scriptId, Object... args) { String functionName = scriptIdToNameMap.get(scriptId); if (functionName == null) { return Futures.immediateFailedFuture( new RuntimeException("No compiled script found for scriptId: [" + scriptId + "]!")); } if (!isBlackListed(scriptId)) { return doInvokeFunction(scriptId, functionName, args); } else { return Futures.immediateFailedFuture(new RuntimeException( "Script is blacklisted due to maximum error count " + getMaxErrors() + "!")); } } @Override public ListenableFuture<Void> release(UUID scriptId) { String functionName = scriptIdToNameMap.get(scriptId); if (functionName != null) { try { scriptIdToNameMap.remove(scriptId); blackListedFunctions.remove(scriptId); doRelease(scriptId, functionName); } catch (Exception e) { return Futures.immediateFailedFuture(e); } } return Futures.immediateFuture(null); } protected abstract ListenableFuture<UUID> doEval(UUID scriptId, String functionName, String scriptBody); protected abstract ListenableFuture<Object> doInvokeFunction(UUID scriptId, String functionName, Object[] args); protected abstract void doRelease(UUID scriptId, String functionName) throws Exception; protected abstract int getMaxErrors(); protected void onScriptExecutionError(UUID scriptId) { blackListedFunctions.computeIfAbsent(scriptId, key -> new AtomicInteger(0)).incrementAndGet(); } private String generateJsScript(JsScriptType scriptType, String functionName, String scriptBody, String... argNames) { switch (scriptType) { case RULE_NODE_SCRIPT: return RuleNodeScriptFactory.generateRuleNodeScript(functionName, scriptBody, argNames); default: throw new RuntimeException("No script factory implemented for scriptType: " + scriptType); } } private boolean isBlackListed(UUID scriptId) { if (blackListedFunctions.containsKey(scriptId)) { AtomicInteger errorCount = blackListedFunctions.get(scriptId); return errorCount.get() >= getMaxErrors(); } else { return false; } } }