Clean up terminated mock instances after a pre-defined period (#34)

* Clean up terminated mock instances after a pre-defined period

* Clean up terminated mock instances after a pre-defined period

* Clean up terminated mock instances after a pre-defined period

* Clean up terminated mock instances after a pre-defined period

Dockerfile

@@ -1,6 +1,6 @@
 FROM java:8
 
-RUN apt-get update
+RUN apt-get clean && apt-get update
 RUN apt-get install -y gradle
 
 WORKDIR /project

README.md

@@ -15,6 +15,10 @@ Aws-mock currently features the following implemented interfaces of Amazon EC2:
 - startInstances
 - terminateInstances
 - describeInstances
+- describeVpcs
+- describeSecurityGroups
+- describeInternetGateways
+- describeRouteTables
 
 This mock can manage a huge amount of EC2 instances, making it super easy for you to test your applications. 
 

src/main/java/com/tlswe/awsmock/common/listener/AppServletContextListener.java

@@ -34,6 +34,16 @@ public class AppServletContextListener implements ServletContextListener {
     private static boolean persistenceEnabled = Boolean
             .parseBoolean(PropertiesUtils.getProperty(Constants.PROP_NAME_PERSISTENCE_ENABLED));
 
+    /**
+     * Period of cleaning up terminated mock ec2 instances.
+     */
+    private static int cleanupTerminatedInstancesPeriod = PropertiesUtils.
+            getIntFromProperty(Constants.PROP_NAME_EC2_CLEANUP_TERMINATED_INSTANCES_TIME_SECONDS);
+
+    /**
+     * Millisecs in a second.
+     */
+    private static final long MILLISECS_IN_A_SECOND = 1000L;
 
     /**
      * Default constructor.
@@ -59,6 +69,10 @@ public final void contextInitialized(final ServletContextEvent sce) {
                 MockEc2Controller.getInstance().restoreAllMockEc2Instances(Arrays.asList(instanceArray));
             }
         }
+
+        // start a timer for cleaning up terminated instances
+        MockEc2Controller.getInstance().
+                cleanupTerminatedInstances(cleanupTerminatedInstancesPeriod);
     }
 
 
@@ -84,6 +98,9 @@ public final void contextDestroyed(final ServletContextEvent sce) {
             instances.toArray(array);
             PersistenceUtils.saveAll(array);
         }
+
+        MockEc2Controller.getInstance().destroyCleanupTerminatedInstanceTimer();
+
         log.info("aws-mock stopped...");
     }
 }

src/main/java/com/tlswe/awsmock/common/util/Constants.java

@@ -48,6 +48,11 @@ public interface Constants {
      */
     String PROP_NAME_XMLNS_CURRENT = "xmlns.current";
 
+    /**
+     * Property name for min boot time of a mock EC2 instance in seconds.
+     */
+    String PROP_NAME_EC2_CLEANUP_TERMINATED_INSTANCES_TIME_SECONDS = "ec2.cleanupTerminatedInstances.time.seconds";
+
     /**
      * Property name for max shutdown time of a mock EC2 instance in milliseconds.
      */

src/main/java/com/tlswe/awsmock/ec2/control/MockEc2Controller.java

@@ -6,6 +6,10 @@
 import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.ScheduledFuture;
+import java.util.concurrent.TimeUnit;
 
 import com.tlswe.awsmock.common.exception.AwsMockException;
 import com.tlswe.awsmock.ec2.cxf_generated.InstanceStateChangeType;
@@ -49,6 +53,15 @@ public final class MockEc2Controller {
     private final Map<String, AbstractMockEc2Instance> allMockEc2Instances =
             new ConcurrentHashMap<String, AbstractMockEc2Instance>();
 
+    /**
+     * Internal timer for cleaning up terminated mock ec2 instances.
+     */
+    private ScheduledExecutorService cleanupTerminatedInstancesTimer = null;
+
+    /**
+     * The result of scheduling a task with a {@link ScheduledExecutorService}.
+     */
+    private ScheduledFuture cleanupTerminatedInstancesScheduledFuture = null;
 
     /**
      * Constructor of MockEc2Controller is made private and only called once by {@link #getInstance()}.
@@ -350,4 +363,49 @@ public void restoreAllMockEc2Instances(final Collection<AbstractMockEc2Instance>
         }
     }
 
+
+    /**
+     * Clean up terminated mock instances after a pre-defined period.
+     * Period is defined in aws-mock.properties (or if not overridden, as defined in aws-mock-default.properties)
+     *
+     * @param period
+     *            time period to clean up terminated instances
+     */
+    public void cleanupTerminatedInstances(final long period) {
+
+        Runnable cleanupTerminatedInstancesTask = new Runnable() {
+
+            /**
+             * this method is triggered every pre-defined period
+             */
+            private String terminatedState = AbstractMockEc2Instance.InstanceState.TERMINATED.getName();
+
+            @Override
+            public void run() {
+                // traverse the map allMockEc2Instances and clean up the terminated ones
+                for (AbstractMockEc2Instance instance : allMockEc2Instances.values()) {
+                    if (terminatedState.equals(instance.getInstanceState().getName())) {
+                        allMockEc2Instances.remove(instance.getInstanceID());
+                    }
+                }
+            }
+
+        };
+
+        cleanupTerminatedInstancesTimer = Executors.newSingleThreadScheduledExecutor();
+        cleanupTerminatedInstancesScheduledFuture = cleanupTerminatedInstancesTimer.
+                scheduleAtFixedRate(cleanupTerminatedInstancesTask, 0L, period, TimeUnit.SECONDS);
+    }
+
+
+    /**
+     * Cancel the internal timer of cleaning up terminated mock ec2 instances.
+     */
+    public void destroyCleanupTerminatedInstanceTimer() {
+        cleanupTerminatedInstancesScheduledFuture.cancel(true);
+        cleanupTerminatedInstancesScheduledFuture = null;
+        cleanupTerminatedInstancesTimer.shutdown();
+        cleanupTerminatedInstancesTimer = null;
+    }
+
 }

src/main/resources/aws-mock-default.properties

@@ -13,6 +13,9 @@ ec2.api.version.current.impl=2013-02-01
 elasticfox.compatible=true
 ec2.api.version.elasticfox=2010-11-15
 
+# period of cleaning up terminated mock ec2 instances
+ec2.cleanupTerminatedInstances.time.seconds=1800
+
 # predefined AMIs
 predefined.mock.ami.1=ami-12345678
 predefined.mock.ami.2=ami-00abcdef