| /* |
| * 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 SF 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.apache.sling.hc.core.impl; |
| import java.util.HashSet; |
| import java.util.Set; |
| |
| import javax.script.Bindings; |
| import javax.script.ScriptEngine; |
| import javax.script.ScriptEngineManager; |
| |
| import org.apache.sling.hc.api.HealthCheck; |
| import org.apache.sling.hc.api.Result; |
| import org.apache.sling.hc.util.FormattingResultLog; |
| import org.apache.sling.scripting.api.BindingsValuesProvider; |
| import org.osgi.service.component.annotations.Activate; |
| import org.osgi.service.component.annotations.Component; |
| import org.osgi.service.component.annotations.ConfigurationPolicy; |
| import org.osgi.service.component.annotations.Reference; |
| import org.osgi.service.component.annotations.ReferenceCardinality; |
| import org.osgi.service.component.annotations.ReferencePolicy; |
| import org.osgi.service.metatype.annotations.Designate; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| /** {@link HealthCheck} that checks a scriptable expression */ |
| @Component( |
| service = HealthCheck.class, |
| configurationPolicy = ConfigurationPolicy.REQUIRE |
| ) |
| @Designate( |
| ocd = ScriptableHealthCheckConfiguration.class, |
| factory = true |
| ) |
| public class ScriptableHealthCheck implements HealthCheck { |
| |
| private final Logger log = LoggerFactory.getLogger(getClass()); |
| private String expression; |
| private String languageExtension; |
| |
| @Reference |
| private ScriptEngineManager scriptEngineManager; |
| |
| @Reference( |
| cardinality = ReferenceCardinality.MULTIPLE, |
| policy = ReferencePolicy.DYNAMIC, |
| service = BindingsValuesProvider.class, |
| target = "(context=healthcheck)" |
| ) |
| private final Set<BindingsValuesProvider> bindingsValuesProviders = new HashSet<BindingsValuesProvider>(); |
| |
| @Activate |
| protected void activate(final ScriptableHealthCheckConfiguration configuration) { |
| expression = configuration.expression(); |
| languageExtension = configuration.language_extension(); |
| |
| log.debug("Activated scriptable health check name={}, languageExtension={}, expression={}", |
| new Object[] {configuration.hc_name(), |
| languageExtension, expression}); |
| } |
| |
| @Override |
| public Result execute() { |
| final FormattingResultLog resultLog = new FormattingResultLog(); |
| resultLog.debug("Checking expression [{}], language extension=[{}]", expression, languageExtension); |
| try { |
| final ScriptEngine engine = scriptEngineManager.getEngineByExtension(languageExtension); |
| if (engine == null) { |
| resultLog.healthCheckError("No ScriptEngine available for extension {}", languageExtension); |
| } else { |
| // Set Bindings, with our ResultLog as a binding first, so that other bindings can use it |
| final Bindings b = engine.createBindings(); |
| b.put(FormattingResultLog.class.getName(), resultLog); |
| synchronized (bindingsValuesProviders) { |
| for(BindingsValuesProvider bvp : bindingsValuesProviders) { |
| log.debug("Adding Bindings provided by {}", bvp); |
| bvp.addBindings(b); |
| } |
| } |
| log.debug("All Bindings added: {}", b.keySet()); |
| |
| final Object value = engine.eval(expression, b); |
| if(value!=null && "true".equals(value.toString().toLowerCase())) { |
| resultLog.debug("Expression [{}] evaluates to true as expected", expression); |
| } else { |
| resultLog.warn("Expression [{}] does not evaluate to true as expected, value=[{}]", expression, value); |
| } |
| } |
| } catch (final Exception e) { |
| resultLog.healthCheckError( |
| "Exception while evaluating expression [{}] with language extension [{}]: {}", |
| expression, languageExtension, e); |
| } |
| return new Result(resultLog); |
| } |
| |
| public void bindBindingsValuesProvider(BindingsValuesProvider bvp) { |
| synchronized (bindingsValuesProviders) { |
| bindingsValuesProviders.add(bvp); |
| } |
| log.debug("{} registered: {}", bvp, bindingsValuesProviders); |
| } |
| |
| public void unbindBindingsValuesProvider(BindingsValuesProvider bvp) { |
| synchronized (bindingsValuesProviders) { |
| bindingsValuesProviders.remove(bvp); |
| } |
| log.debug("{} unregistered: {}", bvp, bindingsValuesProviders); |
| } |
| } |