Java tutorial
/************************************************************************* * Copyright 2009-2015 Eucalyptus Systems, Inc. * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; version 3 of the License. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see http://www.gnu.org/licenses/. * * Please contact Eucalyptus Systems, Inc., 6755 Hollister Ave., Goleta * CA 93117, USA or visit http://www.eucalyptus.com/licenses/ if you need * additional information or have any questions. ************************************************************************/ package com.eucalyptus.simpleworkflow.common.client; import java.beans.Introspector; import java.io.IOException; import java.io.StringReader; import java.lang.reflect.Field; import java.lang.reflect.Method; import java.lang.reflect.Modifier; import java.lang.reflect.Proxy; import java.net.ConnectException; import java.util.UUID; import javax.annotation.Nonnull; import org.apache.http.NoHttpResponseException; import org.apache.log4j.Logger; import org.codehaus.jackson.annotate.JsonIgnoreProperties; import org.codehaus.jackson.map.ObjectMapper; import org.mule.api.MessagingException; import com.amazonaws.AmazonServiceException; import com.amazonaws.ClientConfiguration; import com.amazonaws.Request; import com.amazonaws.Response; import com.amazonaws.auth.AWSCredentialsProvider; import com.amazonaws.handlers.RequestHandler2; import com.amazonaws.services.simpleworkflow.AmazonSimpleWorkflow; import com.amazonaws.services.simpleworkflow.AmazonSimpleWorkflowClient; import com.amazonaws.services.simpleworkflow.flow.ActivityWorker; import com.amazonaws.services.simpleworkflow.flow.JsonDataConverter; import com.amazonaws.services.simpleworkflow.flow.WorkerBase; import com.amazonaws.services.simpleworkflow.flow.WorkflowWorker; import com.amazonaws.util.json.JSONException; import com.eucalyptus.auth.AuthException; import com.eucalyptus.auth.principal.User; import com.eucalyptus.auth.tokens.SecurityTokenAWSCredentialsProvider; import com.eucalyptus.component.ComponentId; import com.eucalyptus.component.ServiceUris; import com.eucalyptus.component.Topology; import com.eucalyptus.configurable.ConfigurableProperty; import com.eucalyptus.configurable.ConfigurablePropertyException; import com.eucalyptus.configurable.PropertyChangeListener; import com.eucalyptus.simpleworkflow.common.SimpleWorkflow; import com.eucalyptus.simpleworkflow.common.model.SimpleWorkflowMessage; import com.eucalyptus.util.Exceptions; import com.eucalyptus.util.UpperCamelPropertyNamingStrategy; import com.fasterxml.jackson.databind.DeserializationFeature; import com.fasterxml.jackson.databind.SerializationFeature; import com.fasterxml.jackson.databind.introspect.AnnotatedMember; import com.fasterxml.jackson.databind.introspect.AnnotatedMethod; import com.fasterxml.jackson.databind.introspect.JacksonAnnotationIntrospector; import com.google.common.base.Strings; import com.google.common.base.Supplier; import com.google.common.reflect.AbstractInvocationHandler; /** * */ public class Config { private static final ObjectMapper mapper = new ObjectMapper() .setPropertyNamingStrategy(new UpperCamelPropertyNamingStrategy()); private static final com.fasterxml.jackson.databind.ObjectMapper workerObjectMapper = buildWorkerObjectMapper(); /** * Parse a JSON format string for AWS SDK for Java ClientConfiguration. * * @param text The configuration in JSON * @return The configuration object */ public static ClientConfiguration buildConfiguration(final String text) { try { return Strings.isNullOrEmpty(text) ? new ClientConfiguration() : mapper.readValue(source(text), ClientConfiguration.class); } catch (final IOException e) { throw new IllegalArgumentException("Invalid configuration: " + e.getMessage(), e); } } public static AmazonSimpleWorkflow buildClient(final Supplier<User> user, final String text) throws AuthException { final AWSCredentialsProvider credentialsProvider = new SecurityTokenAWSCredentialsProvider(user); final AmazonSimpleWorkflowClient client = new AmazonSimpleWorkflowClient(credentialsProvider, buildConfiguration(text)); client.setEndpoint(ServiceUris.remote(Topology.lookup(SimpleWorkflow.class)).toString()); client.addRequestHandler(new RequestHandler2() { @Override public void beforeRequest(final Request<?> request) { // Add nonce to ensure unique request signature request.addHeader("Euca-Nonce", UUID.randomUUID().toString()); } @Override public void afterResponse(final Request<?> request, final Response<?> response) { } @Override public void afterError(final Request<?> request, final Response<?> response, final Exception e) { final String errorMessage = Strings.nullToEmpty(e.getMessage()); boolean resetEndpoint = false; if (Exceptions.isCausedBy(e, JSONException.class) && (errorMessage.contains("Response Code: 404") || errorMessage.contains("Response Code: 503"))) { resetEndpoint = true; } else if (Exceptions.isCausedBy(e, ConnectException.class)) { resetEndpoint = true; } else if (Exceptions.isCausedBy(e, NoHttpResponseException.class)) { resetEndpoint = true; } if (resetEndpoint) { try { client.setEndpoint(ServiceUris.remote(Topology.lookup(SimpleWorkflow.class)).toString()); } catch (final Exception e2) { // retry on next failure } } if (e instanceof AmazonServiceException) { final int status = ((AmazonServiceException) e).getStatusCode(); if (status == 403) { credentialsProvider.refresh(); } } } }); return client; } public static WorkflowWorker buildWorkflowWorker(final Class<? extends ComponentId> componentIdClass, final AmazonSimpleWorkflow client, final String domain, final String taskList, final String text) { final WorkflowWorker workflowWorker = new WorkflowWorker(client, domain, taskList); workflowWorker.setRegisterDomain(true); workflowWorker.setDefaultConverter(new JsonDataConverter(workerObjectMapper)); configure(workflowWorker, text); Package workerPackage = null; for (final Class<?> workflowImplementation : WorkflowRegistry.lookupWorkflows(componentIdClass)) { try { if (workerPackage == null) { workerPackage = workflowImplementation.getPackage(); } workflowWorker.addWorkflowImplementationType(workflowImplementation); } catch (InstantiationException | IllegalAccessException e) { throw new IllegalArgumentException("Invalid workflow implementation: " + workflowImplementation, e); } } perhapsSetExceptionHandler(workerPackage, "decision", workflowWorker); return workflowWorker; } public static ActivityWorker buildActivityWorker(final Class<? extends ComponentId> componentIdClass, final AmazonSimpleWorkflow client, final String domain, final String taskList, final String text) { final ActivityWorker activityWorker = configure(new ActivityWorker(client, domain, taskList), text); activityWorker.setDataConverter(new JsonDataConverter(workerObjectMapper)); Package workerPackage = null; for (final Class<?> activitiesImplementation : WorkflowRegistry.lookupActivities(componentIdClass)) { try { if (workerPackage == null) { workerPackage = activitiesImplementation.getPackage(); } activityWorker.addActivitiesImplementation(activitiesImplementation.newInstance()); } catch (InstantiationException | IllegalAccessException | NoSuchMethodException e) { throw new IllegalArgumentException("Invalid activities implementation: " + activitiesImplementation, e); } } perhapsSetExceptionHandler(workerPackage, "activity", activityWorker); return activityWorker; } private static <T extends WorkerBase> T configure(final T worker, final String text) { try { return Strings.isNullOrEmpty(text) ? worker : mapper.updatingReader(worker).<T>readValue(source(text)); } catch (IOException e) { throw new IllegalArgumentException("Invalid configuration: " + e.getMessage(), e); } } private static void perhapsSetExceptionHandler(final Package logPackage, final String type, final WorkerBase worker) { if (logPackage != null) { final Logger logger = Logger.getLogger(logPackage.getName()); worker.setUncaughtExceptionHandler(new Thread.UncaughtExceptionHandler() { @Override public void uncaughtException(final Thread t, final Throwable e) { if (Exceptions.isCausedBy(e, ConnectException.class)) { logger.warn("Connection error (retrying) for " + type + " worker " + t.getName() + "/" + t.getId()); } else if (Exceptions.isCausedBy(e, AmazonServiceException.class) && 403 == (Exceptions.findCause(e, AmazonServiceException.class)).getStatusCode()) { logger.warn("Authentication failure (retrying) for " + type + " worker " + t.getName() + "/" + t.getId()); } else { logger.error("Error in " + type + " worker " + t.getName() + "/" + t.getId(), e); } } }); } } private static StringReader source(final String text) { return new StringReader(text) { @Override public String toString() { return "property"; } // overridden for better source in error message }; } public static final class NameValidatingChangeListener implements PropertyChangeListener { @Override public void fireChange(final ConfigurableProperty t, final Object newValue) throws ConfigurablePropertyException { if (newValue == null || !SimpleWorkflowMessage.FieldRegexValue.NAME_256.pattern() .matcher(newValue.toString()).matches()) { throw new ConfigurablePropertyException("Value length must be 1 - 256 characters"); } } } public static final class ClientConfigurationValidatingChangeListener implements PropertyChangeListener { @Override public void fireChange(final ConfigurableProperty t, final Object newValue) throws ConfigurablePropertyException { if (newValue != null && !newValue.toString().trim().isEmpty()) try { Config.buildConfiguration(newValue.toString().trim()); } catch (final IllegalArgumentException e) { throw new ConfigurablePropertyException(e.getMessage()); } } } public static final class ActivityWorkerConfigurationValidatingChangeListener implements PropertyChangeListener { @Override public void fireChange(final ConfigurableProperty t, final Object newValue) throws ConfigurablePropertyException { if (newValue != null && !newValue.toString().trim().isEmpty()) try { // dummy values used for validating JSON configuration Config.buildActivityWorker(SimpleWorkflow.class, client(), "domain", "task-list", newValue.toString().trim()); } catch (final IllegalArgumentException e) { throw new ConfigurablePropertyException(e.getMessage()); } } } public static final class WorkflowWorkerConfigurationValidatingChangeListener implements PropertyChangeListener { @Override public void fireChange(final ConfigurableProperty t, final Object newValue) throws ConfigurablePropertyException { if (newValue != null && !newValue.toString().trim().isEmpty()) try { // dummy values used for validating JSON configuration Config.buildWorkflowWorker(SimpleWorkflow.class, client(), "domain", "task-list", newValue.toString().trim()); } catch (final IllegalArgumentException e) { throw new ConfigurablePropertyException(e.getMessage()); } } } private static AmazonSimpleWorkflow client() { return (AmazonSimpleWorkflow) Proxy.newProxyInstance(AmazonSimpleWorkflow.class.getClassLoader(), new Class<?>[] { AmazonSimpleWorkflow.class }, new AbstractInvocationHandler() { @Override protected Object handleInvocation(@Nonnull final Object o, @Nonnull final Method method, @Nonnull final Object[] objects) throws Throwable { throw new Exception("dummy-client"); } }); } private static com.fasterxml.jackson.databind.ObjectMapper buildWorkerObjectMapper() { final com.fasterxml.jackson.databind.ObjectMapper workerObjectMapper = new com.fasterxml.jackson.databind.ObjectMapper(); workerObjectMapper.setAnnotationIntrospector(new JacksonAnnotationIntrospector() { private static final long serialVersionUID = 1L; @Override public boolean hasIgnoreMarker(final AnnotatedMember m) { return isMethodBackedByTransientField(m) || super.hasIgnoreMarker(m); } }); workerObjectMapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false); workerObjectMapper.configure(SerializationFeature.FAIL_ON_EMPTY_BEANS, false); workerObjectMapper.addMixInAnnotations(MessagingException.class, MuleMixin.class); workerObjectMapper.enableDefaultTyping(com.fasterxml.jackson.databind.ObjectMapper.DefaultTyping.NON_FINAL); return workerObjectMapper; } private static boolean isMethodBackedByTransientField(final AnnotatedMember m) { boolean isMethodBackedByTransientField = false; if (m instanceof AnnotatedMethod) { final String fieldName = Introspector .decapitalize(com.eucalyptus.util.Strings.trimPrefix("get", m.getName())); for (final Field field : m.getMember().getDeclaringClass().getDeclaredFields()) { if (fieldName.equals(field.getName())) { isMethodBackedByTransientField = Modifier.isTransient(field.getModifiers()); break; } } } return isMethodBackedByTransientField; } @JsonIgnoreProperties({ "failingMessageProcessor" }) private static final class MuleMixin { } }