Changes to PAP infrastructure to support PDP

Modified PapActivator to implement the Startable interface and used
that to manage it instead of the original method names.
Replaced pdp-common enums with models-pdp enums.
Added the use of the Registry.
Added parameters to be used for PDP interaction.
Added DAO interface classes.
Modified HTTP client, in junit tests, to use GSON instead of Jackson.
Removed DAO code, as the interfaces are not merged into policy/common
yet.
Added pdpParameters to default json config file.
Changed tabs to spaces in json files.

Removed "internal" classes that were moved to models-pdp.

Change-Id: I969a7747e926680ad403557b44a0a52d289fb6d9
Issue-ID: POLICY-1542
Signed-off-by: Jim Hahn <jrh3@att.com>

1 files changed, 74 insertions, 92 deletions

diff --git a/main/src/main/java/org/onap/policy/pap/main/startstop/PapActivator.java b/main/src/main/java/org/onap/policy/pap/main/startstop/PapActivator.java
index 3334d81a..913e661d 100644
--- a/main/src/main/java/org/onap/policy/pap/main/startstop/PapActivator.java
+++ b/main/src/main/java/org/onap/policy/pap/main/startstop/PapActivator.java
@@ -21,18 +21,22 @@
 
 package org.onap.policy.pap.main.startstop;
 
+import java.util.Arrays;
 import java.util.Properties;
-import lombok.Getter;
-import lombok.Setter;
 import org.onap.policy.common.endpoints.event.comm.TopicEndpoint;
+import org.onap.policy.common.endpoints.event.comm.TopicSource;
+import org.onap.policy.common.endpoints.listeners.MessageTypeDispatcher;
+import org.onap.policy.common.endpoints.listeners.RequestIdDispatcher;
 import org.onap.policy.common.parameters.ParameterService;
-import org.onap.policy.common.utils.services.ServiceManager;
-import org.onap.policy.common.utils.services.ServiceManagerException;
-import org.onap.policy.pap.main.PolicyPapException;
+import org.onap.policy.common.utils.services.Registry;
+import org.onap.policy.common.utils.services.ServiceManagerContainer;
+import org.onap.policy.models.pdp.concepts.PdpStatus;
+import org.onap.policy.models.pdp.enums.PdpMessageType;
+import org.onap.policy.pap.main.PapConstants;
+import org.onap.policy.pap.main.PolicyPapRuntimeException;
 import org.onap.policy.pap.main.parameters.PapParameterGroup;
 import org.onap.policy.pap.main.rest.PapRestServer;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
+import org.onap.policy.pap.main.rest.PapStatisticsManager;
 
 /**
  * This class wraps a distributor so that it can be activated as a complete service
@@ -40,28 +44,28 @@ import org.slf4j.LoggerFactory;
  *
  * @author Ram Krishna Verma (ram.krishna.verma@est.tech)
  */
-public class PapActivator {
-
-    private static final Logger LOGGER = LoggerFactory.getLogger(PapActivator.class);
+public class PapActivator extends ServiceManagerContainer {
+    private static final String[] MSG_TYPE_NAMES = {"messageName"};
+    private static final String[] REQ_ID_NAMES = {"response", "responseTo"};
 
     private final PapParameterGroup papParameterGroup;
 
     /**
-     * The current activator.
+     * The PAP REST API server.
      */
-    @Getter
-    private static volatile PapActivator current = null;
+    private PapRestServer restServer;
 
     /**
-     * Used to stop the services.
+     * Listens for messages on the topic, decodes them into a {@link PdpStatus} message,
+     * and then dispatches them to {@link #reqIdDispatcher}.
      */
-    private final ServiceManager manager;
-
-    @Getter
-    @Setter(lombok.AccessLevel.PRIVATE)
-    private volatile boolean alive = false;
+    private final MessageTypeDispatcher msgDispatcher;
 
-    private PapRestServer restServer;
+    /**
+     * Listens for {@link PdpStatus} messages and then routes them to the listener
+     * associated with the ID of the originating request.
+     */
+    private final RequestIdDispatcher<PdpStatus> reqIdDispatcher;
 
     /**
      * Instantiate the activator for policy pap as a complete service.
@@ -70,66 +74,55 @@ public class PapActivator {
      * @param topicProperties properties used to configure the topics
      */
     public PapActivator(final PapParameterGroup papParameterGroup, Properties topicProperties) {
+        super("Policy PAP");
+
         TopicEndpoint.manager.addTopicSinks(topicProperties);
         TopicEndpoint.manager.addTopicSources(topicProperties);
 
-        this.papParameterGroup = papParameterGroup;
+        try {
+            this.papParameterGroup = papParameterGroup;
+            papParameterGroup.getRestServerParameters().setName(papParameterGroup.getName());
+
+            this.msgDispatcher = new MessageTypeDispatcher(MSG_TYPE_NAMES);
+            this.reqIdDispatcher = new RequestIdDispatcher<>(PdpStatus.class, REQ_ID_NAMES);
+
+        } catch (RuntimeException e) {
+            throw new PolicyPapRuntimeException(e);
+        }
+
+        this.msgDispatcher.register(PdpMessageType.PDP_STATUS.name(), this.reqIdDispatcher);
+
+        final Object pdpUpdateLock = new Object();
 
         // @formatter:off
-        this.manager = new ServiceManager()
-                        .addAction("topics",
-                            () -> TopicEndpoint.manager.start(),
-                            () -> TopicEndpoint.manager.shutdown())
-                        .addAction("register parameters",
-                            () -> registerToParameterService(papParameterGroup),
-                            () -> deregisterToParameterService(papParameterGroup))
-                        .addAction("REST server",
-                            () -> startPapRestServer(),
-                            () -> restServer.stop())
-                        .addAction("set alive",
-                            () -> setAlive(true),
-                            () -> setAlive(false));
-        // @formatter:on
+        addAction("PAP parameters",
+            () -> ParameterService.register(papParameterGroup),
+            () -> ParameterService.deregister(papParameterGroup.getName()));
 
-        current = this;
-    }
+        addAction("dispatcher",
+            () -> registerDispatcher(),
+            () -> unregisterDispatcher());
 
-    /**
-     * Initialize pap as a complete service.
-     *
-     * @throws PolicyPapException on errors in initializing the service
-     */
-    public void initialize() throws PolicyPapException {
-        if (isAlive()) {
-            throw new IllegalStateException("activator already initialized");
-        }
+        addAction("topics",
+            () -> TopicEndpoint.manager.start(),
+            () -> TopicEndpoint.manager.shutdown());
 
-        try {
-            LOGGER.debug("Policy pap starting as a service . . .");
-            manager.start();
-            LOGGER.debug("Policy pap started as a service");
-        } catch (final ServiceManagerException exp) {
-            LOGGER.error("Policy pap service startup failed");
-            throw new PolicyPapException(exp.getMessage(), exp);
-        }
-    }
+        addAction("PAP statistics",
+            () -> Registry.register(PapConstants.REG_STATISTICS_MANAGER, new PapStatisticsManager()),
+            () -> Registry.unregister(PapConstants.REG_STATISTICS_MANAGER));
 
-    /**
-     * Terminate policy pap.
-     *
-     * @throws PolicyPapException on errors in terminating the service
-     */
-    public void terminate() throws PolicyPapException {
-        if (!isAlive()) {
-            throw new IllegalStateException("activator is not running");
-        }
+        addAction("PDP modification lock",
+            () -> Registry.register(PapConstants.REG_PDP_MODIFY_LOCK, pdpUpdateLock),
+            () -> Registry.unregister(PapConstants.REG_PDP_MODIFY_LOCK));
 
-        try {
-            manager.stop();
-        } catch (final ServiceManagerException exp) {
-            LOGGER.error("Policy pap service termination failed");
-            throw new PolicyPapException(exp.getMessage(), exp);
-        }
+        addAction("REST server",
+            () -> restServer = new PapRestServer(papParameterGroup.getRestServerParameters()),
+            () -> { });
+
+        addAction("REST server thread",
+            () -> restServer.start(),
+            () -> restServer.stop());
+        // @formatter:on
     }
 
     /**
@@ -142,33 +135,22 @@ public class PapActivator {
     }
 
     /**
-     * Method to register the parameters to Common Parameter Service.
-     *
-     * @param papParameterGroup the pap parameter group
+     * Registers the dispatcher with the topic source(s).
      */
-    public void registerToParameterService(final PapParameterGroup papParameterGroup) {
-        ParameterService.register(papParameterGroup);
-    }
-
-    /**
-     * Method to deregister the parameters from Common Parameter Service.
-     *
-     * @param papParameterGroup the pap parameter group
-     */
-    public void deregisterToParameterService(final PapParameterGroup papParameterGroup) {
-        ParameterService.deregister(papParameterGroup.getName());
+    private void registerDispatcher() {
+        for (TopicSource source : TopicEndpoint.manager
+                        .getTopicSources(Arrays.asList(PapConstants.TOPIC_POLICY_PDP_PAP))) {
+            source.register(msgDispatcher);
+        }
     }
 
     /**
-     * Starts the pap rest server using configuration parameters.
-     *
-     * @throws PolicyPapException if server start fails
+     * Unregisters the dispatcher from the topic source(s).
      */
-    private void startPapRestServer() throws PolicyPapException {
-        papParameterGroup.getRestServerParameters().setName(papParameterGroup.getName());
-        restServer = new PapRestServer(papParameterGroup.getRestServerParameters());
-        if (!restServer.start()) {
-            throw new PolicyPapException("Failed to start pap rest server. Check log for more details...");
+    private void unregisterDispatcher() {
+        for (TopicSource source : TopicEndpoint.manager
+                        .getTopicSources(Arrays.asList(PapConstants.TOPIC_POLICY_PDP_PAP))) {
+            source.unregister(msgDispatcher);
         }
     }
 }