Merge pull request #86 from newrelic/feature/random-ws-reconnect-inte…

…rval

Introduced random reconnection delay in WS connection

newrelic-security-agent/src/main/java/com/newrelic/agent/security/intcodeagent/utils/CommonUtils.java

@@ -24,6 +24,7 @@
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.nio.file.attribute.PosixFilePermissions;
+import java.security.SecureRandom;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Stack;
@@ -34,6 +35,8 @@ public class CommonUtils {
     public static final String POLICY_WRITE_FAILED = "policy write failed : ";
     public static final String POLICY_WRITTEN_TO_FILE = "policy written to file : ";
 
+    public static SecureRandom secureRandom = new SecureRandom();
+
     public static boolean validateCollectorPolicyParameterSchema(AgentPolicyParameters policyParameters) {
 
         try {
@@ -149,4 +152,15 @@ public static void deleteRolloverLogFiles(String fileName, int max) {
             }
         }
     }
+
+
+    /**
+     * Generate random int between range start to end. Both inclusive.
+     * @param start lower bound
+     * @param end upper bound
+     * @return random int
+     */
+    public static int generateSecureRandomBetween(int start, int end) {
+        return secureRandom.nextInt(end-start) + start;
+    }
 }

newrelic-security-agent/src/main/java/com/newrelic/agent/security/intcodeagent/websocket/WSClient.java

@@ -212,7 +212,9 @@ public void onClose(int code, String reason, boolean remote) {
         }
 
         if (code != CloseFrame.POLICY_VALIDATION && code != CloseFrame.NORMAL) {
-            WSReconnectionST.getInstance().submitNewTaskSchedule(15);
+            int delay = CommonUtils.generateSecureRandomBetween(5, 15);
+            logger.log(LogLevel.INFO, String.format(WSUtils.NEXT_WS_CONNECTION_ATTEMPT_WILL_BE_IN_S_SECONDS, delay), WSReconnectionST.class.getName());
+            WSReconnectionST.getInstance().submitNewTaskSchedule(delay);
         }
     }
 

newrelic-security-agent/src/main/java/com/newrelic/agent/security/intcodeagent/websocket/WSReconnectionST.java

@@ -3,7 +3,9 @@
 import com.newrelic.agent.security.intcodeagent.filelogging.FileLoggerThreadPool;
 import com.newrelic.agent.security.intcodeagent.filelogging.LogLevel;
 import com.newrelic.agent.security.intcodeagent.logging.IAgentConstants;
+import com.newrelic.agent.security.intcodeagent.utils.CommonUtils;
 
+import java.security.SecureRandom;
 import java.util.concurrent.*;
 import java.util.concurrent.atomic.AtomicInteger;
 
@@ -31,7 +33,9 @@ public void run() {
                 logger.postLogMessageIfNecessary(LogLevel.SEVERE, ERROR_WHILE_WS_RECONNECTION + e.getMessage() + COLON_SEPARATOR + e.getCause(), e, WSClient.class.getName());
             } finally {
                 if (!WSUtils.isConnected()) {
-                    futureTask = scheduledService.schedule(runnable, 15, TimeUnit.SECONDS);
+                    int delay = CommonUtils.generateSecureRandomBetween(5, 15);
+                    logger.log(LogLevel.INFO, String.format(WSUtils.NEXT_WS_CONNECTION_ATTEMPT_WILL_BE_IN_S_SECONDS, delay), WSReconnectionST.class.getName());
+                    futureTask = scheduledService.schedule(runnable, delay, TimeUnit.SECONDS);
                 }
             }
         }

newrelic-security-agent/src/main/java/com/newrelic/agent/security/intcodeagent/websocket/WSUtils.java

@@ -5,6 +5,7 @@
 import java.util.concurrent.atomic.AtomicBoolean;
 
 public class WSUtils {
+    public static final String NEXT_WS_CONNECTION_ATTEMPT_WILL_BE_IN_S_SECONDS = "Next WS connection attempt will be in %s seconds";
     private static WSUtils instance;
     private static final Object lock = new Object();