Bug fix

Introduced more robust code which enables sending a message only when a publisher is available
Introduced better logging

Change-Id: I94a6fdb4612de192c24511445f1236cdce94b403

slo-violation-detector/src/main/java/slo_violation_detector_engine/generic/Runnables.java

@@ -15,6 +15,7 @@ import java.time.Clock;
 import java.util.Collections;
 import java.util.Date;
 import java.util.NoSuchElementException;
+import java.util.logging.Level;
 import java.util.logging.Logger;
 
 import static configuration.Constants.*;
@@ -74,6 +75,22 @@ public class Runnables {
         Runnable severity_calculation_runnable = () -> {
             BrokerPublisher persistent_publisher = new BrokerPublisher(topic_for_severity_announcement, broker_ip,broker_port,broker_username,broker_password, amq_library_configuration_location);
 
+            int attempts = 1;
+            while (persistent_publisher.is_publisher_null()){
+                if (attempts<=2) {
+                    persistent_publisher = new BrokerPublisher(topic_for_severity_announcement, broker_ip, broker_port, broker_username, broker_password, amq_library_configuration_location);
+                }else{
+                    Logger.getGlobal().log(Level.WARNING,"Will now attempt to reset the BrokerPublisher connector");
+                    persistent_publisher = new BrokerPublisher(topic_for_severity_announcement, broker_ip, broker_port, broker_username, broker_password, amq_library_configuration_location,true);
+                }
+                try {
+                    Thread.sleep(3000);
+                } catch (InterruptedException e) {
+                    throw new RuntimeException(e);
+                }
+                attempts++;
+            }
+
             while (!detector.stop_signal.get()) {
                 synchronized (detector.PREDICTION_EXISTS) {
                     while (!detector.PREDICTION_EXISTS.getValue()) {
@@ -116,6 +133,7 @@ public class Runnables {
                         continue;
                     }
                     Logger.getGlobal().log(info_logging_level, "Targeted_prediction_time " + targeted_prediction_time);
+                    BrokerPublisher finalPersistent_publisher = persistent_publisher;
                     Runnable internal_severity_calculation_runnable = () -> {
                         try {
                             synchronized (detector.PREDICTION_EXISTS) {
@@ -142,7 +160,7 @@ public class Runnables {
                                 severity_json.put("severity", rule_severity);
                                 severity_json.put("probability", slo_violation_probability);
                                 severity_json.put("predictionTime", targeted_prediction_time);
-                                persistent_publisher.publish(severity_json.toJSONString(), Collections.singleton(detector.get_application_name()));
+                                finalPersistent_publisher.publish(severity_json.toJSONString(), Collections.singleton(detector.get_application_name()));
                             }
 
                             detector.getSubcomponent_state().slo_violation_event_recording_queue.add(System.currentTimeMillis());

slo-violation-detector/src/main/java/slo_violation_detector_engine/generic/SLOViolationDetectorStateUtils.java

@@ -25,11 +25,14 @@ public class SLOViolationDetectorStateUtils {
             URI absolute_configuration_file_path = new File(configuration_file_location).toURI();
             URI relative_configuration_file_path = base_project_path.relativize(absolute_configuration_file_path);
             Logger.getGlobal().log(info_logging_level, "This is the base project path:" + base_project_path);
-            return new FileInputStream(base_project_path.getPath() + relative_configuration_file_path);
+            String configuration_path = base_project_path.getPath() + relative_configuration_file_path;
+            Logger.getGlobal().log(info_logging_level, "Loading configuration from path: "+configuration_path);
+            return new FileInputStream(configuration_path);
         }else{
             if (base_project_path == null || base_project_path.getPath().equals(EMPTY)) {
                 base_project_path = new File(custom_properties_file_path).toURI();
             }
+            Logger.getGlobal().log(info_logging_level, "Loading configuration from path: "+base_project_path);
             return new FileInputStream(base_project_path.getPath());
         }
     }

slo-violation-detector/src/main/java/utility_beans/broker_communication/BrokerPublisher.java

@@ -30,9 +30,13 @@ public class BrokerPublisher {
     private int broker_port;
 
     public BrokerPublisher(String topic, String broker_ip, int broker_port, String brokerUsername, String brokerPassword, String amqLibraryConfigurationLocation) {
+        this(topic,broker_ip,broker_port,brokerUsername,brokerPassword,amqLibraryConfigurationLocation,false);
+    }
+    public BrokerPublisher(String topic, String broker_ip, int broker_port, String brokerUsername, String brokerPassword, String amqLibraryConfigurationLocation, boolean hard_initialize_connector) {
         boolean able_to_initialize_BrokerPublisher = topic!=null && broker_ip!=null && brokerUsername!=null && brokerPassword!=null && !topic.equals(EMPTY) && !broker_ip.equals(EMPTY) && !brokerUsername.equals(EMPTY) && !brokerPassword.equals(EMPTY);
 
         if (!able_to_initialize_BrokerPublisher){
+            Logger.getGlobal().log(Level.SEVERE,"Could not initialize BrokerPublisher");
             return;
         }
         boolean publisher_configuration_changed;
@@ -52,7 +56,7 @@ public class BrokerPublisher {
         }
 
 
-        if (publisher_configuration_changed){
+        if (publisher_configuration_changed || hard_initialize_connector){
 //            for (String current_broker_ip : broker_and_topics_to_publish_to.keySet()){
             Logger.getGlobal().log(Level.INFO,"Publisher configuration changed, creating new connector at  "+broker_ip+" for topic "+topic);
             if (active_connector!=null) {
@@ -105,12 +109,16 @@ public class BrokerPublisher {
             } catch (ParseException p) {
                 Logger.getGlobal().log(Level.WARNING, "Could not parse the string content to be published to the broker as json, which is the following: "+json_string_content);
             }
-            if (private_publisher_instance != null) {
+            if (!is_publisher_null()) {
                 private_publisher_instance.send(json_object);
             } else {
-                Logger.getGlobal().log(Level.SEVERE, "Could not send message to AMQP broker, as the broker ip to be used has not been specified");
+                Logger.getGlobal().log(Level.SEVERE, "Could not send message to AMQP broker, as the private publisher instance is null");
             }
         }
     }
+
+    public boolean is_publisher_null(){
+        return (private_publisher_instance == null);
+    }
 }