2 files changed, 151 insertions, 0 deletions
diff --git a/aai-failover/src/main/java/org/onap/aai/failover/FailoverAspect.java b/aai-failover/src/main/java/org/onap/aai/failover/FailoverAspect.java
new file mode 100644
index 00000000..ee21d167
--- /dev/null
+++ b/aai-failover/src/main/java/org/onap/aai/failover/FailoverAspect.java
@@ -0,0 +1,93 @@
+/**
+ * ============LICENSE_START=======================================================
+ * org.onap.aai
+ * ================================================================================
+ * Copyright © 2017-2018 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * 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.
+ * ============LICENSE_END=========================================================
+ */
+package org.onap.aai.failover;
+
+import org.aspectj.lang.ProceedingJoinPoint;
+import org.aspectj.lang.annotation.Around;
+import org.aspectj.lang.annotation.Aspect;
+import org.aspectj.lang.reflect.MethodSignature;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.stereotype.Component;
+
+import java.util.Date;
+import java.util.concurrent.atomic.AtomicLong;
+
+@Aspect
+@Component
+public class FailoverAspect {
+
+    private final Logger LOGGER = LoggerFactory.getLogger(FailoverAspect.class);
+
+    private final FailoverMonitor failoverMonitor;
+    private final AtomicLong atomicLong;
+
+    public FailoverAspect(FailoverMonitor failoverMonitor){
+        this.failoverMonitor = failoverMonitor;
+        this.atomicLong = new AtomicLong(1l);
+    }
+
+    /*
+     * By default, check for the existence of the following file: /opt/app/failover/failover.properties
+     *
+     * If the file exists, open the file as properties
+     * and find the following property: is_primary
+     * Check if the following value is set to true
+     * If it is set to true, then proceed with running the scheduled task
+     * and store the current value into an thread safe variable
+     *
+     * If the file doesn't exist, then proceed with the execution of scheduled task
+     * as if it is the primary site since there is nothing helping identify if its primary
+     *
+     * If the application is not in an kubernetes environment, in order to emulate the behavior
+     * search for the file in the classpath of application
+     * If the file can be found then it will behavior similar to above in kubernetes env
+     *
+     * Since some tasks such as ones in history is constantly getting data
+     * with little time in between each runs of the task to get latest data
+     * we don't want to log too much when the failover properties isn't being changed
+     * So it will check the last time this got executed and see if its more than two minutes have passed
+     * then if it did, then it will log current status
+     */
+    @Around("@annotation(org.springframework.scheduling.annotation.Scheduled)")
+    public void preSchedule(ProceedingJoinPoint pointcut) throws Throwable {
+
+        Object target             = pointcut.getTarget();
+        MethodSignature signature = (MethodSignature) pointcut.getSignature();
+        String method             = signature.getMethod().getName();
+
+        if(failoverMonitor.shouldRun()){
+            atomicLong.set(1l);
+            pointcut.proceed();
+        } else {
+            long currentTime = new Date().getTime();
+            long lastMessageTime = atomicLong.get();
+
+            if((currentTime - lastMessageTime) > 120000){
+                atomicLong.compareAndSet(lastMessageTime, new Date().getTime());
+                LOGGER.debug("Not proceeding the task {}#{} due to is_primary set to false in failover.properties",
+                    target.getClass(),
+                    method
+                );
+            }
+        }
+    }
+}
+
diff --git a/aai-failover/src/main/java/org/onap/aai/failover/FailoverMonitor.java b/aai-failover/src/main/java/org/onap/aai/failover/FailoverMonitor.java
new file mode 100644
index 00000000..cadddc24
--- /dev/null
+++ b/aai-failover/src/main/java/org/onap/aai/failover/FailoverMonitor.java
@@ -0,0 +1,58 @@
+/**
+ * ============LICENSE_START=======================================================
+ * org.onap.aai
+ * ================================================================================
+ * Copyright © 2017-2018 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * 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.
+ * ============LICENSE_END=========================================================
+ */
+package org.onap.aai.failover;
+
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.stereotype.Component;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.Properties;
+
+@Component
+public class FailoverMonitor {
+
+    private static final String IS_PRIMARY = "is_primary";
+    private static final String TRUE = "true";
+    private static final String DEFAULT_FOR_PRIMARY = TRUE;
+
+    @Value("${failover.location:/opt/app/failover/failover.properties}")
+    private String failoverPropertiesPath;
+
+    public boolean shouldRun() throws IOException {
+
+        Path failoverPath = Paths.get(failoverPropertiesPath);
+
+        if(Files.exists(failoverPath)){
+            Properties properties = new Properties();
+            try (InputStream is = Files.newInputStream(failoverPath)){
+                properties.load(is);
+                // If the property is_primary is missing then it should proceed
+                return TRUE.equals(properties.getProperty(IS_PRIMARY, DEFAULT_FOR_PRIMARY));
+            }
+        } else {
+            // If the file doesn't exist, then scheduled task should execute
+            return true;
+        }
+    }
+}