org.apache.oozie.FaultInjection Maven / Gradle / Ivy
/**
* 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 ASF 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.oozie;
import org.apache.oozie.util.XLog;
/**
* Fault Injection support class. Concrete classes should be available only during testing, not in production.
* To activate fault injection the {@link #FAULT_INJECTION} system property must be set to true.
When fault
* injection is activated, the concrete class (specified by name) will be call for activation.
Concrete classes
* should be activated by presense of a second system property.
This fault injection pattern provides 3 levels of
* safeguard: a general 'fault injection' system property, the availabity of of the concrete 'fault injection' class in
* the classpath, a specifi 'fault injection' system property.
Refer to the SkipCommitFaultInjection
* class in the test classes for an example.
*/
public abstract class FaultInjection {
public static final String FAULT_INJECTION = "oozie.fault.injection";
private static FaultInjection getFaultInjection(String className) {
if (Boolean.parseBoolean(System.getProperty(FAULT_INJECTION, "false"))) {
try {
Class klass = Thread.currentThread().getContextClassLoader().loadClass(className);
return (FaultInjection) klass.newInstance();
}
catch (ClassNotFoundException ex) {
XLog.getLog(FaultInjection.class).warn("Trying to activate fault injection in production", ex);
}
catch (IllegalAccessException ex) {
throw new RuntimeException(XLog.format("Could not initialize [{0}]", className, ex), ex);
}
catch (InstantiationException ex) {
throw new RuntimeException(XLog.format("Could not initialize [{0}]", className, ex), ex);
}
}
return null;
}
public static boolean activate(String className) {
FaultInjection fi = getFaultInjection(className);
if (fi != null) {
className = className.substring(className.lastIndexOf(".") + 1);
if (fi.activate()) {
XLog.getLog(FaultInjection.class).warn("FAULT INJECTION, ACTIVATING [{0}]", className);
return true;
}
else {
XLog.getLog(FaultInjection.class).warn("FAULT INJECTION, DID NOT ACTIVATE [{0}]", className);
}
}
return false;
}
public static void deactivate(String className) {
FaultInjection fi = getFaultInjection(className);
if (fi != null) {
className = className.substring(className.lastIndexOf(".") + 1);
if (fi.isActive()) {
XLog.getLog(FaultInjection.class).warn("FAULT INJECTION, DEACTIVATING [{0}]", className);
fi.deactivate();
}
else {
XLog.getLog(FaultInjection.class).warn("FAULT INJECTION, CANNOT DEACTIVATE, NOT ACTIVE [{0}]",
className);
}
}
}
public static boolean isActive(String className) {
FaultInjection fi = getFaultInjection(className);
if (fi != null) {
className = className.substring(className.lastIndexOf(".") + 1);
if (fi.isActive()) {
XLog.getLog(FaultInjection.class).warn("FAULT INJECTION, ACTIVE [{0}]", className);
return true;
}
else {
XLog.getLog(FaultInjection.class).warn("FAULT INJECTION, NOT ACTIVE [{0}]", className);
}
}
return false;
}
public abstract boolean activate();
public abstract void deactivate();
public abstract boolean isActive();
}