Refactor common code from UsecasesEventManager

Created ClEventManagerWithSteps, as a subclass of
ControlLoopEventManager.  It contains the "Steps" to be performed and
also deals with outcomes.
Created ClEventManagerWithEvent, as a subclass of that.  It contains a
VirtualControlLoopEvent object, and uses that to populate data used by
the superclass.
Updates per review comments:
- made loadPolicy() protected
- refactored another level to manage operation outcomes

Issue-ID: POLICY-3262
Change-Id: Ibf5dd114746ae26e04fe37d562273fc81dd8cfbe
Signed-off-by: Jim Hahn <jrh3@att.com>

2 files changed, 27 insertions, 462 deletions

diff --git a/controlloop/common/controller-usecases/src/main/java/org/onap/policy/drools/apps/controller/usecases/UsecasesEventManager.java b/controlloop/common/controller-usecases/src/main/java/org/onap/policy/drools/apps/controller/usecases/UsecasesEventManager.java
index d586240d9..4db243408 100644
--- a/controlloop/common/controller-usecases/src/main/java/org/onap/policy/drools/apps/controller/usecases/UsecasesEventManager.java
+++ b/controlloop/common/controller-usecases/src/main/java/org/onap/policy/drools/apps/controller/usecases/UsecasesEventManager.java
@@ -36,37 +36,21 @@ import static org.onap.policy.drools.apps.controller.usecases.UsecasesConstants.
 import static org.onap.policy.drools.apps.controller.usecases.UsecasesConstants.VSERVER_PROV_STATUS;
 import static org.onap.policy.drools.apps.controller.usecases.UsecasesConstants.VSERVER_VSERVER_NAME;
 
-import java.util.ArrayDeque;
 import java.util.Deque;
-import java.util.LinkedHashMap;
-import java.util.LinkedList;
 import java.util.Map;
 import java.util.Set;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
-import lombok.Getter;
-import lombok.NonNull;
-import lombok.Setter;
-import lombok.ToString;
-import org.apache.commons.lang3.StringUtils;
 import org.drools.core.WorkingMemory;
-import org.kie.api.runtime.rule.FactHandle;
-import org.onap.policy.controlloop.ControlLoopEventStatus;
 import org.onap.policy.controlloop.ControlLoopException;
-import org.onap.policy.controlloop.ControlLoopNotificationType;
-import org.onap.policy.controlloop.ControlLoopOperation;
 import org.onap.policy.controlloop.ControlLoopResponse;
 import org.onap.policy.controlloop.VirtualControlLoopEvent;
-import org.onap.policy.controlloop.VirtualControlLoopNotification;
-import org.onap.policy.controlloop.actorserviceprovider.OperationFinalResult;
 import org.onap.policy.controlloop.actorserviceprovider.OperationOutcome;
 import org.onap.policy.controlloop.actorserviceprovider.OperationProperties;
-import org.onap.policy.controlloop.actorserviceprovider.OperationResult;
-import org.onap.policy.controlloop.actorserviceprovider.TargetType;
 import org.onap.policy.controlloop.actorserviceprovider.parameters.ControlLoopOperationParams;
 import org.onap.policy.controlloop.drl.legacy.ControlLoopParams;
 import org.onap.policy.controlloop.eventmanager.ActorConstants;
-import org.onap.policy.controlloop.eventmanager.ControlLoopEventManager;
+import org.onap.policy.controlloop.eventmanager.ClEventManagerWithEvent;
 import org.onap.policy.controlloop.eventmanager.StepContext;
 import org.onap.policy.drools.apps.controller.usecases.step.AaiCqStep2;
 import org.onap.policy.drools.apps.controller.usecases.step.AaiGetPnfStep2;
@@ -75,14 +59,7 @@ import org.onap.policy.drools.apps.controller.usecases.step.GetTargetEntityStep2
 import org.onap.policy.drools.apps.controller.usecases.step.GuardStep2;
 import org.onap.policy.drools.apps.controller.usecases.step.LockStep2;
 import org.onap.policy.drools.apps.controller.usecases.step.Step2;
-import org.onap.policy.drools.domain.models.operational.ActorOperation;
-import org.onap.policy.drools.domain.models.operational.Operation;
-import org.onap.policy.drools.domain.models.operational.OperationalTarget;
-import org.onap.policy.drools.system.PolicyEngine;
-import org.onap.policy.drools.system.PolicyEngineConstants;
 import org.onap.policy.sdnr.PciMessage;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
 
 /**
  * Manager for a single control loop event. Once this has been created, the event can be
@@ -90,19 +67,11 @@ import org.slf4j.LoggerFactory;
  * involves at least one step. As a step is processed, additional preprocessor steps may
  * be pushed onto the queue (e.g., locks, A&AI queries, guards).
  */
-@ToString(onlyExplicitlyIncluded = true)
-public class UsecasesEventManager extends ControlLoopEventManager implements StepContext {
+public class UsecasesEventManager extends ClEventManagerWithEvent<Step2> implements StepContext {
 
-    private static final Logger logger = LoggerFactory.getLogger(UsecasesEventManager.class);
     private static final long serialVersionUID = -1216568161322872641L;
 
     /**
-     * Maximum number of steps, for a single policy, allowed in the queue at a time. This
-     * prevents an infinite loop occurring with calls to {@link #loadPreprocessorSteps()}.
-     */
-    public static final int MAX_STEPS = 30;
-
-    /**
      * If there's a failure from one of these actors, then the TOSCA processing should be
      * aborted.
      */
@@ -132,94 +101,6 @@ public class UsecasesEventManager extends ControlLoopEventManager implements Ste
                     OperationProperties.AAI_VNF_MODEL, OperationProperties.AAI_SERVICE,
                     OperationProperties.AAI_RESOURCE_VNF, UsecasesConstants.AAI_DEFAULT_GENERIC_VNF);
 
-    public enum State {
-        LOAD_POLICY, POLICY_LOADED, AWAITING_OUTCOME, DONE
-    }
-
-    public enum NewEventStatus {
-        FIRST_ONSET, SUBSEQUENT_ONSET, FIRST_ABATEMENT, SUBSEQUENT_ABATEMENT, SYNTAX_ERROR
-    }
-
-    @Getter
-    private final VirtualControlLoopEvent event;
-
-    /**
-     * Request ID, as a String.
-     */
-    private final String requestIdStr;
-
-    @Getter
-    @Setter
-    private State state;
-
-    /**
-     * {@code True} if the event has been accepted (i.e., an "ACTIVE" notification has
-     * been delivered), {@code false} otherwise.
-     */
-    @Getter
-    @Setter
-    private boolean accepted;
-
-    /**
-     * Queue of steps waiting to be performed.
-     */
-    @Getter
-    private final transient Deque<Step2> steps = new ArrayDeque<>(6);
-
-    /**
-     * Number of attempts, so far, for the current step.
-     */
-    @Getter
-    private int attempts;
-
-    /**
-     * Policy currently being processed.
-     */
-    private Operation policy;
-
-    /**
-     * Result of the last policy operation. This is just a place where the rules can store
-     * the value for passing to {@link #loadNextPolicy()}.
-     */
-    @Getter
-    @Setter
-    private OperationResult result = OperationResult.SUCCESS;
-
-    @ToString.Include
-    private int numOnsets = 1;
-    @ToString.Include
-    private int numAbatements = 0;
-
-    private VirtualControlLoopEvent abatement = null;
-
-    /**
-     * Full history of operations that have been processed by the rules. This includes the
-     * items in {@link #partialHistory}.
-     */
-    @Getter
-    private final transient Deque<OperationOutcome2> fullHistory = new LinkedList<>();
-
-    /**
-     * History of operations that have been processed by the rules for the current policy.
-     * When a step is started, its "start" outcome is added. However, once it completes,
-     * its "start" outcome is removed and the "completed" outcome is added.
-     */
-    @Getter
-    private final transient Deque<OperationOutcome2> partialHistory = new LinkedList<>();
-
-    @Getter
-    private OperationFinalResult finalResult = null;
-
-    /**
-     * Message to be placed into the final notification. Typically used when something
-     * causes processing to abort.
-     */
-    @Getter
-    private String finalMessage = null;
-
-    private final transient WorkingMemory workMem;
-    private transient FactHandle factHandle;
-
 
     /**
      * Constructs the object.
@@ -233,9 +114,7 @@ public class UsecasesEventManager extends ControlLoopEventManager implements Ste
     public UsecasesEventManager(ControlLoopParams params, VirtualControlLoopEvent event, WorkingMemory workMem)
                     throws ControlLoopException {
 
-        super(params, event.getRequestId());
-
-        checkEventSyntax(event);
+        super(params, event, workMem);
 
         if (isClosedLoopDisabled(event)) {
             throw new IllegalStateException("is-closed-loop-disabled is set to true on VServer or VNF");
@@ -244,127 +123,24 @@ public class UsecasesEventManager extends ControlLoopEventManager implements Ste
         if (isProvStatusInactive(event)) {
             throw new IllegalStateException("prov-status is not ACTIVE on VServer or VNF");
         }
-
-        this.event = event;
-        this.workMem = workMem;
-        this.requestIdStr = getRequestId().toString();
-    }
-
-    @Override
-    public void destroy() {
-        for (Step2 step : steps) {
-            step.cancel();
-        }
-
-        super.destroy();
-    }
-
-    /**
-     * Starts the manager and loads the first policy.
-     *
-     * @throws ControlLoopException if the processor cannot get a policy
-     */
-    public void start() throws ControlLoopException {
-        if (!isActive()) {
-            throw new IllegalStateException("manager is no longer active");
-        }
-
-        if ((factHandle = workMem.getFactHandle(this)) == null) {
-            throw new IllegalStateException("manager is not in working memory");
-        }
-
-        if (!steps.isEmpty()) {
-            throw new IllegalStateException("manager already started");
-        }
-
-        loadPolicy();
     }
 
-    /**
-     * Indicates that processing has been aborted.
-     *
-     * @param finalState final state
-     * @param finalResult final result
-     * @param finalMessage final message
-     */
-    public void abort(@NonNull State finalState, OperationFinalResult finalResult, String finalMessage) {
-        this.state = finalState;
-        this.finalResult = finalResult;
-        this.finalMessage = finalMessage;
-    }
-
-    /**
-     * Loads the next policy.
-     *
-     * @param lastResult result from the last policy
-     *
-     * @throws ControlLoopException if the processor cannot get a policy
+    /*
+     * This is needed to satisfy drools.
      */
-    public void loadNextPolicy(@NonNull OperationResult lastResult) throws ControlLoopException {
-        getProcessor().nextPolicyForResult(lastResult);
-        loadPolicy();
-    }
-
-    /**
-     * Loads the current policy.
-     *
-     * @throws ControlLoopException if the processor cannot get a policy
-     */
-    private void loadPolicy() throws ControlLoopException {
-        partialHistory.clear();
-
-        if ((finalResult = getProcessor().checkIsCurrentPolicyFinal()) != null) {
-            // final policy - nothing more to do
-            return;
-        }
-
-        policy = getProcessor().getCurrentPolicy();
-
-        ActorOperation actor = policy.getActorOperation();
-
-        OperationalTarget target = actor.getTarget();
-        String targetType = (target != null ? target.getTargetType() : null);
-        Map<String, String> entityIds = (target != null ? target.getEntityIds() : null);
-
-        // convert policy payload from Map<String,String> to Map<String,Object>
-        Map<String, Object> payload = new LinkedHashMap<>();
-        if (actor.getPayload() != null) {
-            payload.putAll(actor.getPayload());
-        }
-
-        // @formatter:off
-        ControlLoopOperationParams params = ControlLoopOperationParams.builder()
-                        .actorService(getActorService())
-                        .actor(actor.getActor())
-                        .operation(actor.getOperation())
-                        .requestId(event.getRequestId())
-                        .executor(getExecutor())
-                        .retry(policy.getRetries())
-                        .timeoutSec(policy.getTimeout())
-                        .targetType(TargetType.toTargetType(targetType))
-                        .targetEntityIds(entityIds)
-                        .payload(payload)
-                        .startCallback(this::onStart)
-                        .completeCallback(this::onComplete)
-                        .build();
-        // @formatter:on
-
-        // load the policy's operation
-        steps.add(new Step2(this, params, event));
+    @Override
+    public Deque<Step2> getSteps() {
+        return super.getSteps();
     }
 
     /**
      * Loads the preprocessor steps needed by the step that's at the front of the queue.
      */
     public void loadPreprocessorSteps() {
-        if (steps.size() >= MAX_STEPS) {
-            throw new IllegalStateException("too many steps");
-        }
-
-        final Step2 step = steps.peek();
+        super.loadPreprocessorSteps();
 
-        // initialize the step so we can query its properties
-        step.init();
+        final Deque<Step2> steps = getSteps();
+        final Step2 step = getSteps().peek();
 
         // determine if any A&AI queries are needed
         boolean needCq = false;
@@ -422,124 +198,13 @@ public class UsecasesEventManager extends ControlLoopEventManager implements Ste
     }
 
     /**
-     * Executes the first step in the queue.
-     *
-     * @return {@code true} if the step was started, {@code false} if it is no longer
-     *         needed (or if the queue is empty)
-     */
-    public boolean executeStep() {
-        attempts = 0;
-
-        Step2 step = steps.peek();
-        if (step == null) {
-            return false;
-        }
-
-        return step.start(getEndTimeMs() - System.currentTimeMillis());
-    }
-
-    /**
-     * Discards the current step, if any.
-     */
-    public void nextStep() {
-        steps.poll();
-    }
-
-    /**
-     * Increments the number of attempts.
-     */
-    public void bumpAttempts() {
-        ++attempts;
-    }
-
-    /**
      * Determines if the TOSCA should be aborted due to the given outcome.
      *
      * @param outcome outcome to examine
      * @return {@code true} if the TOSCA should be aborted, {@code false} otherwise
      */
     public boolean isAbort(OperationOutcome outcome) {
-        return (outcome.getResult() != OperationResult.SUCCESS && ABORT_ACTORS.contains(outcome.getActor()));
-    }
-
-    /**
-     * Adds the outcome to the history.
-     *
-     * @param outcome outcome to add
-     */
-    public void addToHistory(OperationOutcome outcome) {
-        OperationOutcome2 last = partialHistory.peekLast();
-
-        if (last != null && last.getOutcome().getEnd() == null
-                        && last.getOutcome().isFor(outcome.getActor(), outcome.getOperation())) {
-            // last item was a "start" - remove it
-            partialHistory.removeLast();
-
-            if (fullHistory.peekLast() == last) {
-                fullHistory.removeLast();
-            }
-        }
-
-        OperationOutcome2 outcome2 = new OperationOutcome2(outcome);
-        partialHistory.add(outcome2);
-        fullHistory.add(outcome2);
-    }
-
-    /**
-     * Makes a notification message for the current operation.
-     *
-     * @return a new notification
-     */
-    public VirtualControlLoopNotification makeNotification() {
-        VirtualControlLoopNotification notif = new VirtualControlLoopNotification(event);
-        notif.setNotification(ControlLoopNotificationType.OPERATION);
-        notif.setFrom("policy");
-        notif.setPolicyVersion(getPolicyVersion());
-
-        if (finalResult != null) {
-            return notif;
-        }
-
-        OperationOutcome2 last = partialHistory.peekLast();
-        if (last == null) {
-            return notif;
-        }
-
-        notif.setMessage(last.getClOperation().toHistory());
-        notif.setHistory(partialHistory.stream().map(OperationOutcome2::getClOperation).collect(Collectors.toList()));
-
-        return notif;
-    }
-
-    /**
-     * Delivers a notification to a topic.
-     *
-     * @param sinkName name of the topic sink
-     * @param notification notification to be published, or {@code null} if nothing is to
-     *        be published
-     * @param notificationType type of notification, used when logging error messages
-     * @param ruleName name of the rule doing the publishing
-     */
-    public <T> void deliver(String sinkName, T notification, String notificationType, String ruleName) {
-        try {
-            if (notification != null) {
-                getPolicyEngineManager().deliver(sinkName, notification);
-            }
-
-        } catch (RuntimeException e) {
-            logger.warn("{}: {}.{}: manager={} exception publishing {}", getClosedLoopControlName(), getPolicyName(),
-                            ruleName, this, notificationType, e);
-        }
-    }
-
-    /**
-     * Get the last operation, as a message.
-     *
-     * @return the last operation, as a message
-     */
-    public String getOperationMessage() {
-        OperationOutcome2 last = fullHistory.peekLast();
-        return (last == null ? null : last.getClOperation().toMessage());
+        return (super.isAbort(outcome) && ABORT_ACTORS.contains(outcome.getActor()));
     }
 
     /**
@@ -548,10 +213,7 @@ public class UsecasesEventManager extends ControlLoopEventManager implements Ste
      * @param outcome operation outcome to store
      */
     public void storeInDataBase(OperationOutcome2 outcome) {
-        String targetEntity = getProperty(OperationProperties.AAI_TARGET_ENTITY);
-
-        getDataManager().store(requestIdStr, event.getClosedLoopControlName(), event, targetEntity,
-                        outcome.getClOperation());
+        storeInDataBase(outcome, getProperty(OperationProperties.AAI_TARGET_ENTITY));
     }
 
     /**
@@ -561,14 +223,7 @@ public class UsecasesEventManager extends ControlLoopEventManager implements Ste
      * @return a new control loop response, or {@code null} if none is required
      */
     public ControlLoopResponse makeControlLoopResponse(OperationOutcome outcome) {
-        ControlLoopResponse clRsp = new ControlLoopResponse();
-        clRsp.setFrom(outcome.getActor());
-        clRsp.setTarget("DCAE");
-        clRsp.setClosedLoopControlName(event.getClosedLoopControlName());
-        clRsp.setPolicyName(event.getPolicyName());
-        clRsp.setPolicyVersion(event.getPolicyVersion());
-        clRsp.setRequestId(event.getRequestId());
-        clRsp.setVersion(event.getVersion());
+        ControlLoopResponse clRsp = super.makeControlLoopResponse(outcome);
 
         Object obj = outcome.getResponse();
         if (!(obj instanceof PciMessage)) {
@@ -584,68 +239,22 @@ public class UsecasesEventManager extends ControlLoopEventManager implements Ste
     }
 
     /**
-     * An event onset/abatement.
-     *
-     * @param newEvent the event
-     * @return the status
-     */
-    public NewEventStatus onNewEvent(VirtualControlLoopEvent newEvent) {
-        try {
-            checkEventSyntax(newEvent);
-
-            if (newEvent.getClosedLoopEventStatus() == ControlLoopEventStatus.ONSET) {
-                if (newEvent.equals(event)) {
-                    return NewEventStatus.FIRST_ONSET;
-                }
-
-                numOnsets++;
-                return NewEventStatus.SUBSEQUENT_ONSET;
-
-            } else {
-                if (abatement == null) {
-                    abatement = newEvent;
-                    numAbatements++;
-                    return NewEventStatus.FIRST_ABATEMENT;
-                } else {
-                    numAbatements++;
-                    return NewEventStatus.SUBSEQUENT_ABATEMENT;
-                }
-            }
-        } catch (ControlLoopException e) {
-            logger.error("{}: onNewEvent threw an exception", this, e);
-            return NewEventStatus.SYNTAX_ERROR;
-        }
-    }
-
-    /**
      * Check an event syntax.
      *
      * @param event the event syntax
      * @throws ControlLoopException if an error occurs
      */
     protected void checkEventSyntax(VirtualControlLoopEvent event) throws ControlLoopException {
-        validateStatus(event);
-        if (StringUtils.isBlank(event.getClosedLoopControlName())) {
-            throw new ControlLoopException("No control loop name");
-        }
-        if (event.getRequestId() == null) {
-            throw new ControlLoopException("No request ID");
-        }
-        if (event.getClosedLoopEventStatus() == ControlLoopEventStatus.ABATED) {
-            return;
-        }
-        if (StringUtils.isBlank(event.getTarget())) {
-            throw new ControlLoopException("No target field");
-        } else if (!VALID_TARGETS.contains(event.getTarget().toLowerCase())) {
-            throw new ControlLoopException("target field invalid");
-        }
+        super.checkEventSyntax(event);
         validateAaiData(event);
     }
 
-    private void validateStatus(VirtualControlLoopEvent event) throws ControlLoopException {
-        if (event.getClosedLoopEventStatus() != ControlLoopEventStatus.ONSET
-                        && event.getClosedLoopEventStatus() != ControlLoopEventStatus.ABATED) {
-            throw new ControlLoopException("Invalid value in closedLoopEventStatus");
+    @Override
+    protected void validateTarget(VirtualControlLoopEvent event) throws ControlLoopException {
+        super.validateTarget(event);
+
+        if (!VALID_TARGETS.contains(event.getTarget().toLowerCase())) {
+            throw new ControlLoopException("target field invalid");
         }
     }
 
@@ -724,51 +333,7 @@ public class UsecasesEventManager extends ControlLoopEventManager implements Ste
     }
 
     @Override
-    public void onStart(OperationOutcome outcome) {
-        super.onStart(outcome);
-        workMem.update(factHandle, this);
-    }
-
-    @Override
-    public void onComplete(OperationOutcome outcome) {
-        super.onComplete(outcome);
-        workMem.update(factHandle, this);
-    }
-
-    @Getter
-    @ToString
-    public class OperationOutcome2 {
-        private final int attempt;
-        private final OperationOutcome outcome;
-        private final ControlLoopOperation clOperation;
-
-        /**
-         * Constructs the object.
-         *
-         * @param outcome outcome of the operation
-         */
-        public OperationOutcome2(OperationOutcome outcome) {
-            this.outcome = outcome;
-            this.attempt = attempts;
-
-            clOperation = outcome.toControlLoopOperation();
-
-            // TODO encode()?
-            OperationalTarget target = policy.getActorOperation().getTarget();
-            String targetStr = (target != null ? target.toString() : null);
-            clOperation.setTarget(targetStr);
-
-            if (outcome.getEnd() == null) {
-                clOperation.setOutcome("Started");
-            } else if (clOperation.getOutcome() == null) {
-                clOperation.setOutcome("");
-            }
-        }
-    }
-
-    // these following methods may be overridden by junit tests
-
-    protected PolicyEngine getPolicyEngineManager() {
-        return PolicyEngineConstants.getManager();
+    protected void loadPolicyStep(ControlLoopOperationParams params) {
+        getSteps().add(new Step2(this, params, getEvent()));
     }
 }
diff --git a/controlloop/common/controller-usecases/src/main/resources/usecases.drl b/controlloop/common/controller-usecases/src/main/resources/usecases.drl
index 12c9849f9..49ab78d71 100644
--- a/controlloop/common/controller-usecases/src/main/resources/usecases.drl
+++ b/controlloop/common/controller-usecases/src/main/resources/usecases.drl
@@ -2,7 +2,7 @@
  * ============LICENSE_START=======================================================
  * ONAP
  * ================================================================================
- * Copyright (C) 2020 AT&T Intellectual Property. All rights reserved.
+ * Copyright (C) 2020-2021 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.
@@ -42,9 +42,9 @@ import org.onap.policy.controlloop.eventmanager.ActorConstants;
 import org.onap.policy.controlloop.eventmanager.Step;
 import org.onap.policy.controlloop.utils.ControlLoopUtils;
 import org.onap.policy.drools.apps.controller.usecases.UsecasesEventManager;
-import org.onap.policy.drools.apps.controller.usecases.UsecasesEventManager.State;
-import org.onap.policy.drools.apps.controller.usecases.UsecasesEventManager.NewEventStatus;
-import org.onap.policy.drools.apps.controller.usecases.UsecasesEventManager.OperationOutcome2;
+import org.onap.policy.controlloop.eventmanager.ClEventManagerWithSteps.State;
+import org.onap.policy.controlloop.eventmanager.ClEventManagerWithOutcome.OperationOutcome2;
+import org.onap.policy.controlloop.eventmanager.ClEventManagerWithEvent.NewEventStatus;
 import org.onap.policy.models.tosca.authorative.concepts.ToscaPolicy;
 
 import org.slf4j.LoggerFactory;