Use BidirectionalTopicClient from policy-common

Also modified "target" to sink in various places, and renamed
various uses of "pair" to "bidirectional" (e.g., TopicPairParams
=> BidirectionalTopicParams).
Also replaced MyExec with PseudoExecutor, from policy-common.
As part of this, extracted the logRequest and logResponse methods
from the Http and Topic classes, moving them into the common
OperationPartial class.
Modified A&AI, SDNC junit tests to use PseudoExecutor.
Added support for incomplete responses on Topics, where multiple
responses may be received for one request
Fixed a duplicate entry in actor.aai pom.

As the changes were already big enough, went ahead and also did the
following to support the APPC Actor:
- Reorganized parameter classes and content.
- Modified anyOf, allOf to take functions instead of futures and handle
  exceptions thrown by any of the functions.  Also added sequence() method.
- Deleted doTask.
- Modified ActorService.config to take a map of maps, not just a map.
- Decided NOT to move anyOf, allOf, and sequence from OperationPartial
  to a utility class, because they depend on "params".

Issue-ID: POLICY-2363
Signed-off-by: Jim Hahn <jrh3@att.com>
Change-Id: I5a8bae05dfef22fe71c57c58f265b9dac20df5c5

17 files changed, 692 insertions, 710 deletions

diff --git a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/ActorService.java b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/ActorService.java
index 2886b1feb..24c2cfc23 100644
--- a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/ActorService.java
+++ b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/ActorService.java
@@ -40,7 +40,7 @@ import org.slf4j.LoggerFactory;
  * {@link #start()} to start all of the actors. When finished using the actor service,
  * invoke {@link #stop()} or {@link #shutdown()}.
  */
-public class ActorService extends StartConfigPartial<Map<String, Object>> {
+public class ActorService extends StartConfigPartial<Map<String, Map<String, Object>>> {
     private static final Logger logger = LoggerFactory.getLogger(ActorService.class);
 
     private final Map<String, Actor> name2actor;
@@ -116,14 +116,14 @@ public class ActorService extends StartConfigPartial<Map<String, Object>> {
     }
 
     @Override
-    protected void doConfigure(Map<String, Object> parameters) {
+    protected void doConfigure(Map<String, Map<String, Object>> parameters) {
         logger.info("configuring actors");
 
         BeanValidationResult valres = new BeanValidationResult("ActorService", parameters);
 
         for (Actor actor : name2actor.values()) {
             String actorName = actor.getName();
-            Map<String, Object> subparams = Util.translateToMap(actorName, parameters.get(actorName));
+            Map<String, Object> subparams = parameters.get(actorName);
 
             if (subparams != null) {
 
diff --git a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/impl/BidirectionalTopicActor.java b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/impl/BidirectionalTopicActor.java
new file mode 100644
index 000000000..1e44a170c
--- /dev/null
+++ b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/impl/BidirectionalTopicActor.java
@@ -0,0 +1,108 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * ONAP
+ * ================================================================================
+ * Copyright (C) 2020 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.policy.controlloop.actorserviceprovider.impl;
+
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.function.Function;
+import org.apache.commons.lang3.tuple.Pair;
+import org.onap.policy.common.endpoints.event.comm.client.BidirectionalTopicClientException;
+import org.onap.policy.controlloop.actorserviceprovider.Util;
+import org.onap.policy.controlloop.actorserviceprovider.parameters.BidirectionalTopicActorParams;
+import org.onap.policy.controlloop.actorserviceprovider.topic.BidirectionalTopicHandler;
+import org.onap.policy.controlloop.actorserviceprovider.topic.BidirectionalTopicManager;
+
+/**
+ * Actor that uses a bidirectional topic. The actor's parameters must be a
+ * {@link BidirectionalTopicActorParams}.
+ */
+public class BidirectionalTopicActor extends ActorImpl implements BidirectionalTopicManager {
+
+    /**
+     * Maps a pair of sink and source topic names to their bidirectional topic.
+     */
+    private final Map<Pair<String, String>, BidirectionalTopicHandler> params2topic = new ConcurrentHashMap<>();
+
+
+    /**
+     * Constructs the object.
+     *
+     * @param name actor's name
+     */
+    public BidirectionalTopicActor(String name) {
+        super(name);
+    }
+
+    @Override
+    protected void doStart() {
+        params2topic.values().forEach(BidirectionalTopicHandler::start);
+        super.doStart();
+    }
+
+    @Override
+    protected void doStop() {
+        params2topic.values().forEach(BidirectionalTopicHandler::stop);
+        super.doStop();
+    }
+
+    @Override
+    protected void doShutdown() {
+        params2topic.values().forEach(BidirectionalTopicHandler::shutdown);
+        params2topic.clear();
+        super.doShutdown();
+    }
+
+    @Override
+    public BidirectionalTopicHandler getTopicHandler(String sinkTopic, String sourceTopic) {
+        Pair<String, String> key = Pair.of(sinkTopic, sourceTopic);
+
+        return params2topic.computeIfAbsent(key, pair -> {
+            try {
+                return makeTopicHandler(sinkTopic, sourceTopic);
+            } catch (BidirectionalTopicClientException e) {
+                throw new IllegalArgumentException(e);
+            }
+        });
+    }
+
+    /**
+     * Translates the parameters to a {@link BidirectionalTopicActorParams} and then
+     * creates a function that will extract operator-specific parameters.
+     */
+    @Override
+    protected Function<String, Map<String, Object>> makeOperatorParameters(Map<String, Object> actorParameters) {
+        String actorName = getName();
+
+        // @formatter:off
+        return Util.translate(actorName, actorParameters, BidirectionalTopicActorParams.class)
+                        .doValidation(actorName)
+                        .makeOperationParameters(actorName);
+        // @formatter:on
+    }
+
+    // may be overridden by junit tests
+
+    protected BidirectionalTopicHandler makeTopicHandler(String sinkTopic, String sourceTopic)
+                    throws BidirectionalTopicClientException {
+
+        return new BidirectionalTopicHandler(sinkTopic, sourceTopic);
+    }
+}
diff --git a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/impl/TopicPairOperation.java b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/impl/BidirectionalTopicOperation.java
index 6b584d7c6..f82015d6b 100644
--- a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/impl/TopicPairOperation.java
+++ b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/impl/BidirectionalTopicOperation.java
@@ -24,40 +24,42 @@ import java.util.List;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.Executor;
 import java.util.concurrent.TimeUnit;
+import java.util.function.BiConsumer;
 import lombok.Getter;
-import org.apache.commons.lang3.tuple.Triple;
-import org.onap.policy.common.endpoints.event.comm.Topic.CommInfrastructure;
-import org.onap.policy.common.endpoints.utils.NetLoggerUtil;
-import org.onap.policy.common.endpoints.utils.PropertyUtils.TriConsumer;
-import org.onap.policy.common.utils.coder.Coder;
+import org.onap.policy.common.endpoints.utils.NetLoggerUtil.EventType;
 import org.onap.policy.common.utils.coder.CoderException;
-import org.onap.policy.common.utils.coder.StandardCoder;
 import org.onap.policy.common.utils.coder.StandardCoderObject;
 import org.onap.policy.controlloop.actorserviceprovider.OperationOutcome;
+import org.onap.policy.controlloop.actorserviceprovider.parameters.BidirectionalTopicParams;
 import org.onap.policy.controlloop.actorserviceprovider.parameters.ControlLoopOperationParams;
-import org.onap.policy.controlloop.actorserviceprovider.parameters.TopicPairParams;
 import org.onap.policy.controlloop.actorserviceprovider.pipeline.PipelineControllerFuture;
+import org.onap.policy.controlloop.actorserviceprovider.topic.BidirectionalTopicHandler;
 import org.onap.policy.controlloop.actorserviceprovider.topic.Forwarder;
-import org.onap.policy.controlloop.actorserviceprovider.topic.TopicPair;
 import org.onap.policy.controlloop.policy.PolicyResult;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 /**
- * Operation that uses a Topic pair.
+ * Operation that uses a bidirectional topic.
  *
  * @param <S> response type
  */
 @Getter
-public abstract class TopicPairOperation<Q, S> extends OperationPartial {
-    private static final Logger logger = LoggerFactory.getLogger(TopicPairOperation.class);
-    private static final Coder coder = new StandardCoder();
+public abstract class BidirectionalTopicOperation<Q, S> extends OperationPartial {
+    private static final Logger logger = LoggerFactory.getLogger(BidirectionalTopicOperation.class);
+
+    /**
+     * Response status.
+     */
+    public enum Status {
+        SUCCESS, FAILURE, STILL_WAITING
+    }
 
     // fields extracted from the operator
 
-    private final TopicPair topicPair;
+    private final BidirectionalTopicHandler topicHandler;
     private final Forwarder forwarder;
-    private final TopicPairParams pairParams;
+    private final BidirectionalTopicParams topicParams;
     private final long timeoutMs;
 
     /**
@@ -73,13 +75,14 @@ public abstract class TopicPairOperation<Q, S> extends OperationPartial {
      * @param operator operator that created this operation
      * @param clazz response class
      */
-    public TopicPairOperation(ControlLoopOperationParams params, TopicPairOperator operator, Class<S> clazz) {
+    public BidirectionalTopicOperation(ControlLoopOperationParams params, BidirectionalTopicOperator operator,
+                    Class<S> clazz) {
         super(params, operator);
-        this.topicPair = operator.getTopicPair();
+        this.topicHandler = operator.getTopicHandler();
         this.forwarder = operator.getForwarder();
-        this.pairParams = operator.getParams();
+        this.topicParams = operator.getParams();
         this.responseClass = clazz;
-        this.timeoutMs = TimeUnit.MILLISECONDS.convert(pairParams.getTimeoutSec(), TimeUnit.SECONDS);
+        this.timeoutMs = TimeUnit.MILLISECONDS.convert(topicParams.getTimeoutSec(), TimeUnit.SECONDS);
     }
 
     /**
@@ -101,18 +104,17 @@ public abstract class TopicPairOperation<Q, S> extends OperationPartial {
         final List<String> expectedKeyValues = getExpectedKeyValues(attempt, request);
 
         final PipelineControllerFuture<OperationOutcome> controller = new PipelineControllerFuture<>();
-        final CompletableFuture<Triple<CommInfrastructure, String, StandardCoderObject>> future =
-                        new CompletableFuture<>();
         final Executor executor = params.getExecutor();
 
         // register a listener BEFORE publishing
 
-        // @formatter:off
-        TriConsumer<CommInfrastructure, String, StandardCoderObject> listener =
-            (infra, rawResponse, scoResponse) -> future.complete(Triple.of(infra, rawResponse, scoResponse));
-        // @formatter:on
-
-        // TODO this currently only allows a single matching response
+        BiConsumer<String, StandardCoderObject> listener = (rawResponse, scoResponse) -> {
+            OperationOutcome latestOutcome = processResponse(outcome, rawResponse, scoResponse);
+            if (latestOutcome != null) {
+                // final response - complete the controller
+                controller.completeAsync(() -> latestOutcome, executor);
+            }
+        };
 
         forwarder.register(expectedKeyValues, listener);
 
@@ -128,16 +130,6 @@ public abstract class TopicPairOperation<Q, S> extends OperationPartial {
             throw e;
         }
 
-
-        // once "future" completes, process the response, and then complete the controller
-
-        // @formatter:off
-        future.thenApplyAsync(
-            triple -> processResponse(triple.getLeft(), outcome, triple.getMiddle(), triple.getRight()),
-                            executor)
-                        .whenCompleteAsync(controller.delayedComplete(), executor);
-        // @formatter:on
-
         return controller;
     }
 
@@ -175,12 +167,11 @@ public abstract class TopicPairOperation<Q, S> extends OperationPartial {
             throw new IllegalArgumentException("cannot encode request", e);
         }
 
-        List<CommInfrastructure> list = topicPair.publish(json);
-        if (list.isEmpty()) {
+        if (!topicHandler.send(json)) {
             throw new IllegalStateException("nothing published");
         }
 
-        logTopicRequest(list, request);
+        logMessage(EventType.OUT, topicHandler.getSinkTopicCommInfrastructure(), topicHandler.getSinkTopic(), request);
     }
 
     /**
@@ -190,15 +181,17 @@ public abstract class TopicPairOperation<Q, S> extends OperationPartial {
      * @param outcome outcome to be populated
      * @param response raw response to process
      * @param scoResponse response, as a {@link StandardCoderObject}
-     * @return the outcome
+     * @return the outcome, or {@code null} if still waiting for completion
      */
-    protected OperationOutcome processResponse(CommInfrastructure infra, OperationOutcome outcome, String rawResponse,
+    protected OperationOutcome processResponse(OperationOutcome outcome, String rawResponse,
                     StandardCoderObject scoResponse) {
 
         logger.info("{}.{}: response received for {}", params.getActor(), params.getOperation(), params.getRequestId());
 
-        logTopicResponse(infra, rawResponse);
+        logMessage(EventType.IN, topicHandler.getSourceTopicCommInfrastructure(), topicHandler.getSourceTopic(),
+                        rawResponse);
 
+        // decode the response
         S response;
         if (responseClass == String.class) {
             response = responseClass.cast(rawResponse);
@@ -216,17 +209,26 @@ public abstract class TopicPairOperation<Q, S> extends OperationPartial {
             }
         }
 
-        if (!isSuccess(rawResponse, response)) {
-            logger.info("{}.{} request failed  for {}", params.getActor(), params.getOperation(),
-                            params.getRequestId());
-            return setOutcome(outcome, PolicyResult.FAILURE);
-        }
+        // check its status
+        switch (detmStatus(rawResponse, response)) {
+            case SUCCESS:
+                logger.info("{}.{} request succeeded for {}", params.getActor(), params.getOperation(),
+                                params.getRequestId());
+                setOutcome(outcome, PolicyResult.SUCCESS);
+                postProcessResponse(outcome, rawResponse, response);
+                return outcome;
 
-        logger.info("{}.{} request succeeded for {}", params.getActor(), params.getOperation(), params.getRequestId());
-        setOutcome(outcome, PolicyResult.SUCCESS);
-        postProcessResponse(outcome, rawResponse, response);
+            case FAILURE:
+                logger.info("{}.{} request failed for {}", params.getActor(), params.getOperation(),
+                                params.getRequestId());
+                return setOutcome(outcome, PolicyResult.FAILURE);
 
-        return outcome;
+            case STILL_WAITING:
+            default:
+                logger.info("{}.{} request incomplete for {}", params.getActor(), params.getOperation(),
+                                params.getRequestId());
+                return null;
+        }
     }
 
     /**
@@ -241,76 +243,11 @@ public abstract class TopicPairOperation<Q, S> extends OperationPartial {
     }
 
     /**
-     * Determines if the response indicates success.
+     * Determines the status of the response.
      *
      * @param rawResponse raw response
      * @param response decoded response
-     * @return {@code true} if the response indicates success, {@code false} otherwise
-     */
-    protected abstract boolean isSuccess(String rawResponse, S response);
-
-    /**
-     * Logs a TOPIC request. If the request is not of type, String, then it attempts to
-     * pretty-print it into JSON before logging.
-     *
-     * @param infrastructures list of communication infrastructures on which it was
-     *        published
-     * @param request request to be logged
-     */
-    protected void logTopicRequest(List<CommInfrastructure> infrastructures, Q request) {
-        if (infrastructures.isEmpty()) {
-            return;
-        }
-
-        String json;
-        try {
-            if (request == null) {
-                json = null;
-            } else if (request instanceof String) {
-                json = request.toString();
-            } else {
-                json = makeCoder().encode(request, true);
-            }
-
-        } catch (CoderException e) {
-            logger.warn("cannot pretty-print request", e);
-            json = request.toString();
-        }
-
-        for (CommInfrastructure infra : infrastructures) {
-            logger.info("[OUT|{}|{}|]{}{}", infra, pairParams.getTarget(), NetLoggerUtil.SYSTEM_LS, json);
-        }
-    }
-
-    /**
-     * Logs a TOPIC response. If the response is not of type, String, then it attempts to
-     * pretty-print it into JSON before logging.
-     *
-     * @param infra communication infrastructure on which the response was received
-     * @param response response to be logged
+     * @return the status of the response
      */
-    protected <T> void logTopicResponse(CommInfrastructure infra, T response) {
-        String json;
-        try {
-            if (response == null) {
-                json = null;
-            } else if (response instanceof String) {
-                json = response.toString();
-            } else {
-                json = makeCoder().encode(response, true);
-            }
-
-        } catch (CoderException e) {
-            logger.warn("cannot pretty-print response", e);
-            json = response.toString();
-        }
-
-        logger.info("[IN|{}|{}|]{}{}", infra, pairParams.getSource(), NetLoggerUtil.SYSTEM_LS, json);
-    }
-
-    // these may be overridden by junit tests
-
-    protected Coder makeCoder() {
-        return coder;
-    }
+    protected abstract Status detmStatus(String rawResponse, S response);
 }
diff --git a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/impl/TopicPairOperator.java b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/impl/BidirectionalTopicOperator.java
index 8ce013388..51689e49b 100644
--- a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/impl/TopicPairOperator.java
+++ b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/impl/BidirectionalTopicOperator.java
@@ -28,24 +28,24 @@ import lombok.Getter;
 import org.onap.policy.common.parameters.ValidationResult;
 import org.onap.policy.controlloop.actorserviceprovider.Operation;
 import org.onap.policy.controlloop.actorserviceprovider.Util;
+import org.onap.policy.controlloop.actorserviceprovider.parameters.BidirectionalTopicParams;
 import org.onap.policy.controlloop.actorserviceprovider.parameters.ControlLoopOperationParams;
 import org.onap.policy.controlloop.actorserviceprovider.parameters.ParameterValidationRuntimeException;
-import org.onap.policy.controlloop.actorserviceprovider.parameters.TopicPairParams;
+import org.onap.policy.controlloop.actorserviceprovider.topic.BidirectionalTopicHandler;
+import org.onap.policy.controlloop.actorserviceprovider.topic.BidirectionalTopicManager;
 import org.onap.policy.controlloop.actorserviceprovider.topic.Forwarder;
 import org.onap.policy.controlloop.actorserviceprovider.topic.SelectorKey;
-import org.onap.policy.controlloop.actorserviceprovider.topic.TopicPair;
-import org.onap.policy.controlloop.actorserviceprovider.topic.TopicPairManager;
 
 /**
- * Operator that uses a pair of topics, one for publishing the request, and another for
- * receiving the response. Topic operators may share a {@link TopicPair}.
+ * Operator that uses a bidirectional topic. Topic operators may share a
+ * {@link BidirectionalTopicHandler}.
  */
-public abstract class TopicPairOperator extends OperatorPartial {
+public abstract class BidirectionalTopicOperator extends OperatorPartial {
 
     /**
-     * Manager from which to get the topic pair.
+     * Manager from which to get the topic handlers.
      */
-    private final TopicPairManager pairManager;
+    private final BidirectionalTopicManager topicManager;
 
     /**
      * Keys used to extract the fields used to select responses for this operator.
@@ -62,13 +62,13 @@ public abstract class TopicPairOperator extends OperatorPartial {
      * will not, thus operations may copy it.
      */
     @Getter
-    private TopicPairParams params;
+    private BidirectionalTopicParams params;
 
     /**
-     * Topic pair associated with the parameters.
+     * Topic handler associated with the parameters.
      */
     @Getter
-    private TopicPair topicPair;
+    private BidirectionalTopicHandler topicHandler;
 
     /**
      * Forwarder associated with the parameters.
@@ -82,27 +82,27 @@ public abstract class TopicPairOperator extends OperatorPartial {
      *
      * @param actorName name of the actor with which this operator is associated
      * @param name operation name
-     * @param pairManager manager from which to get the topic pair
+     * @param topicManager manager from which to get the topic handler
      * @param selectorKeys keys used to extract the fields used to select responses for
      *        this operator
      */
-    public TopicPairOperator(String actorName, String name, TopicPairManager pairManager,
+    public BidirectionalTopicOperator(String actorName, String name, BidirectionalTopicManager topicManager,
                     List<SelectorKey> selectorKeys) {
         super(actorName, name);
-        this.pairManager = pairManager;
+        this.topicManager = topicManager;
         this.selectorKeys = selectorKeys;
     }
 
     @Override
     protected void doConfigure(Map<String, Object> parameters) {
-        params = Util.translate(getFullName(), parameters, TopicPairParams.class);
+        params = Util.translate(getFullName(), parameters, BidirectionalTopicParams.class);
         ValidationResult result = params.validate(getFullName());
         if (!result.isValid()) {
             throw new ParameterValidationRuntimeException("invalid parameters", result);
         }
 
-        topicPair = pairManager.getTopicPair(params.getSource(), params.getTarget());
-        forwarder = topicPair.addForwarder(selectorKeys);
+        topicHandler = topicManager.getTopicHandler(params.getSinkTopic(), params.getSourceTopic());
+        forwarder = topicHandler.addForwarder(selectorKeys);
     }
 
     /**
@@ -112,19 +112,21 @@ public abstract class TopicPairOperator extends OperatorPartial {
      * @param <S> response type
      * @param actorName actor name
      * @param operation operation name
-     * @param pairManager manager from which to get the topic pair
+     * @param topicManager manager from which to get the topic handler
      * @param operationMaker function to make an operation
      * @param keys keys used to extract the fields used to select responses for this
      *        operator
      * @return a new operator
      */
     // @formatter:off
-    public static <Q,S> TopicPairOperator makeOperator(String actorName, String operation, TopicPairManager pairManager,
-                    BiFunction<ControlLoopOperationParams, TopicPairOperator, TopicPairOperation<Q,S>> operationMaker,
+    public static <Q, S> BidirectionalTopicOperator makeOperator(String actorName, String operation,
+                    BidirectionalTopicManager topicManager,
+                    BiFunction<ControlLoopOperationParams, BidirectionalTopicOperator,
+                        BidirectionalTopicOperation<Q, S>> operationMaker,
                     SelectorKey... keys) {
         // @formatter:off
 
-        return makeOperator(actorName, operation, pairManager, Arrays.asList(keys), operationMaker);
+        return makeOperator(actorName, operation, topicManager, Arrays.asList(keys), operationMaker);
     }
 
     /**
@@ -134,19 +136,21 @@ public abstract class TopicPairOperator extends OperatorPartial {
      * @param <S> response type
      * @param actorName actor name
      * @param operation operation name
-     * @param pairManager manager from which to get the topic pair
+     * @param topicManager manager from which to get the topic handler
      * @param keys keys used to extract the fields used to select responses for
      *        this operator
      * @param operationMaker function to make an operation
      * @return a new operator
      */
     // @formatter:off
-    public static <Q,S> TopicPairOperator makeOperator(String actorName, String operation, TopicPairManager pairManager,
+    public static <Q,S> BidirectionalTopicOperator makeOperator(String actorName, String operation,
+                    BidirectionalTopicManager topicManager,
                     List<SelectorKey> keys,
-                    BiFunction<ControlLoopOperationParams, TopicPairOperator, TopicPairOperation<Q,S>> operationMaker) {
+                    BiFunction<ControlLoopOperationParams, BidirectionalTopicOperator,
+                        BidirectionalTopicOperation<Q,S>> operationMaker) {
         // @formatter:on
 
-        return new TopicPairOperator(actorName, operation, pairManager, keys) {
+        return new BidirectionalTopicOperator(actorName, operation, topicManager, keys) {
             @Override
             public synchronized Operation buildOperation(ControlLoopOperationParams params) {
                 return operationMaker.apply(params, this);
diff --git a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/impl/HttpOperation.java b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/impl/HttpOperation.java
index ba75f0be6..f1829d79a 100644
--- a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/impl/HttpOperation.java
+++ b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/impl/HttpOperation.java
@@ -33,9 +33,7 @@ import org.onap.policy.common.endpoints.event.comm.Topic.CommInfrastructure;
 import org.onap.policy.common.endpoints.http.client.HttpClient;
 import org.onap.policy.common.endpoints.utils.NetLoggerUtil;
 import org.onap.policy.common.endpoints.utils.NetLoggerUtil.EventType;
-import org.onap.policy.common.utils.coder.Coder;
 import org.onap.policy.common.utils.coder.CoderException;
-import org.onap.policy.common.utils.coder.StandardCoder;
 import org.onap.policy.controlloop.actorserviceprovider.OperationOutcome;
 import org.onap.policy.controlloop.actorserviceprovider.parameters.ControlLoopOperationParams;
 import org.onap.policy.controlloop.actorserviceprovider.parameters.HttpParams;
@@ -52,7 +50,6 @@ import org.slf4j.LoggerFactory;
 @Getter
 public abstract class HttpOperation<T> extends OperationPartial {
     private static final Logger logger = LoggerFactory.getLogger(HttpOperation.class);
-    private static final Coder coder = new StandardCoder();
 
     /**
      * Operator that created this operation.
@@ -171,7 +168,7 @@ public abstract class HttpOperation<T> extends OperationPartial {
 
         String strResponse = HttpClient.getBody(rawResponse, String.class);
 
-        logRestResponse(url, strResponse);
+        logMessage(EventType.IN, CommInfrastructure.REST, url, strResponse);
 
         T response;
         if (responseClass == String.class) {
@@ -224,63 +221,10 @@ public abstract class HttpOperation<T> extends OperationPartial {
         return (rawResponse.getStatus() == 200);
     }
 
-    /**
-     * Logs a REST request. If the request is not of type, String, then it attempts to
-     * pretty-print it into JSON before logging.
-     *
-     * @param url request URL
-     * @param request request to be logged
-     */
-    public <Q> void logRestRequest(String url, Q request) {
-        String json;
-        try {
-            if (request == null) {
-                json = null;
-            } else if (request instanceof String) {
-                json = request.toString();
-            } else {
-                json = makeCoder().encode(request, true);
-            }
-
-        } catch (CoderException e) {
-            logger.warn("cannot pretty-print request", e);
-            json = request.toString();
-        }
-
-        NetLoggerUtil.log(EventType.OUT, CommInfrastructure.REST, url, json);
-        logger.info("[OUT|{}|{}|]{}{}", CommInfrastructure.REST, url, NetLoggerUtil.SYSTEM_LS, json);
-    }
-
-    /**
-     * Logs a REST response. If the response is not of type, String, then it attempts to
-     * pretty-print it into JSON before logging.
-     *
-     * @param url request URL
-     * @param response response to be logged
-     */
-    public <S> void logRestResponse(String url, S response) {
-        String json;
-        try {
-            if (response == null) {
-                json = null;
-            } else if (response instanceof String) {
-                json = response.toString();
-            } else {
-                json = makeCoder().encode(response, true);
-            }
-
-        } catch (CoderException e) {
-            logger.warn("cannot pretty-print response", e);
-            json = response.toString();
-        }
-
-        NetLoggerUtil.log(EventType.IN, CommInfrastructure.REST, url, json);
-        logger.info("[IN|{}|{}|]{}{}", CommInfrastructure.REST, url, NetLoggerUtil.SYSTEM_LS, json);
-    }
-
-    // these may be overridden by junit tests
-
-    protected Coder makeCoder() {
-        return coder;
+    @Override
+    public <Q> String logMessage(EventType direction, CommInfrastructure infra, String sink, Q request) {
+        String json = super.logMessage(direction, infra, sink, request);
+        NetLoggerUtil.log(direction, infra, sink, json);
+        return json;
     }
 }
diff --git a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/impl/OperationPartial.java b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/impl/OperationPartial.java
index d00b88bb5..0b3497197 100644
--- a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/impl/OperationPartial.java
+++ b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/impl/OperationPartial.java
@@ -20,7 +20,12 @@
 
 package org.onap.policy.controlloop.actorserviceprovider.impl;
 
+import java.util.ArrayDeque;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.LinkedList;
 import java.util.List;
+import java.util.Queue;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.CompletionException;
 import java.util.concurrent.Executor;
@@ -28,6 +33,14 @@ import java.util.concurrent.TimeUnit;
 import java.util.concurrent.TimeoutException;
 import java.util.function.BiConsumer;
 import java.util.function.Function;
+import java.util.function.Supplier;
+import java.util.function.UnaryOperator;
+import org.onap.policy.common.endpoints.event.comm.Topic.CommInfrastructure;
+import org.onap.policy.common.endpoints.utils.NetLoggerUtil;
+import org.onap.policy.common.endpoints.utils.NetLoggerUtil.EventType;
+import org.onap.policy.common.utils.coder.Coder;
+import org.onap.policy.common.utils.coder.CoderException;
+import org.onap.policy.common.utils.coder.StandardCoder;
 import org.onap.policy.controlloop.ControlLoopOperation;
 import org.onap.policy.controlloop.actorserviceprovider.CallbackManager;
 import org.onap.policy.controlloop.actorserviceprovider.Operation;
@@ -53,8 +66,8 @@ import org.slf4j.LoggerFactory;
  * be done to cancel that particular operation.
  */
 public abstract class OperationPartial implements Operation {
-
     private static final Logger logger = LoggerFactory.getLogger(OperationPartial.class);
+    private static final Coder coder = new StandardCoder();
     public static final long DEFAULT_RETRY_WAIT_MS = 1000L;
 
     // values extracted from the operator
@@ -470,103 +483,110 @@ public abstract class OperationPartial implements Operation {
      * Similar to {@link CompletableFuture#anyOf(CompletableFuture...)}, but it cancels
      * any outstanding futures when one completes.
      *
-     * @param futures futures for which to wait
-     * @return a future to cancel or await an outcome. If this future is canceled, then
-     *         all of the futures will be canceled
+     * @param futureMakers function to make a future. If the function returns
+     *        {@code null}, then no future is created for that function. On the other
+     *        hand, if the function throws an exception, then the previously created
+     *        functions are canceled and the exception is re-thrown
+     * @return a future to cancel or await an outcome, or {@code null} if no futures were
+     *         created. If this future is canceled, then all of the futures will be
+     *         canceled
      */
-    protected CompletableFuture<OperationOutcome> anyOf(List<CompletableFuture<OperationOutcome>> futures) {
-
-        // convert list to an array
-        @SuppressWarnings("rawtypes")
-        CompletableFuture[] arrFutures = futures.toArray(new CompletableFuture[futures.size()]);
+    protected CompletableFuture<OperationOutcome> anyOf(
+                    @SuppressWarnings("unchecked") Supplier<CompletableFuture<OperationOutcome>>... futureMakers) {
 
-        @SuppressWarnings("unchecked")
-        CompletableFuture<OperationOutcome> result = anyOf(arrFutures);
-        return result;
+        return anyOf(Arrays.asList(futureMakers));
     }
 
     /**
-     * Same as {@link CompletableFuture#anyOf(CompletableFuture...)}, but it cancels any
-     * outstanding futures when one completes.
+     * Similar to {@link CompletableFuture#anyOf(CompletableFuture...)}, but it cancels
+     * any outstanding futures when one completes.
      *
-     * @param futures futures for which to wait
-     * @return a future to cancel or await an outcome. If this future is canceled, then
-     *         all of the futures will be canceled
+     * @param futureMakers function to make a future. If the function returns
+     *        {@code null}, then no future is created for that function. On the other
+     *        hand, if the function throws an exception, then the previously created
+     *        functions are canceled and the exception is re-thrown
+     * @return a future to cancel or await an outcome, or {@code null} if no futures were
+     *         created. If this future is canceled, then all of the futures will be
+     *         canceled. Similarly, when this future completes, any incomplete futures
+     *         will be canceled
      */
     protected CompletableFuture<OperationOutcome> anyOf(
-                    @SuppressWarnings("unchecked") CompletableFuture<OperationOutcome>... futures) {
+                    List<Supplier<CompletableFuture<OperationOutcome>>> futureMakers) {
+
+        PipelineControllerFuture<OperationOutcome> controller = new PipelineControllerFuture<>();
+
+        CompletableFuture<OperationOutcome>[] futures =
+                        attachFutures(controller, futureMakers, UnaryOperator.identity());
+
+        if (futures.length == 0) {
+            // no futures were started
+            return null;
+        }
 
         if (futures.length == 1) {
             return futures[0];
         }
 
-        final Executor executor = params.getExecutor();
-        final PipelineControllerFuture<OperationOutcome> controller = new PipelineControllerFuture<>();
-
-        attachFutures(controller, futures);
-
-        // @formatter:off
-        CompletableFuture.anyOf(futures)
-                            .thenApply(object -> (OperationOutcome) object)
-                            .whenCompleteAsync(controller.delayedComplete(), executor);
-        // @formatter:on
+        CompletableFuture.anyOf(futures).thenApply(outcome -> (OperationOutcome) outcome)
+                        .whenCompleteAsync(controller.delayedComplete(), params.getExecutor());
 
         return controller;
     }
 
     /**
-     * Similar to {@link CompletableFuture#allOf(CompletableFuture...)}, but it cancels
-     * the futures if returned future is canceled. The future returns the "worst" outcome,
-     * based on priority (see {@link #detmPriority(OperationOutcome)}).
+     * Similar to {@link CompletableFuture#allOf(CompletableFuture...)}.
      *
-     * @param futures futures for which to wait
-     * @return a future to cancel or await an outcome. If this future is canceled, then
-     *         all of the futures will be canceled
+     * @param futureMakers function to make a future. If the function returns
+     *        {@code null}, then no future is created for that function. On the other
+     *        hand, if the function throws an exception, then the previously created
+     *        functions are canceled and the exception is re-thrown
+     * @return a future to cancel or await an outcome, or {@code null} if no futures were
+     *         created. If this future is canceled, then all of the futures will be
+     *         canceled
      */
-    protected CompletableFuture<OperationOutcome> allOf(List<CompletableFuture<OperationOutcome>> futures) {
-
-        // convert list to an array
-        @SuppressWarnings("rawtypes")
-        CompletableFuture[] arrFutures = futures.toArray(new CompletableFuture[futures.size()]);
+    protected CompletableFuture<OperationOutcome> allOf(
+                    @SuppressWarnings("unchecked") Supplier<CompletableFuture<OperationOutcome>>... futureMakers) {
 
-        @SuppressWarnings("unchecked")
-        CompletableFuture<OperationOutcome> result = allOf(arrFutures);
-        return result;
+        return allOf(Arrays.asList(futureMakers));
     }
 
     /**
-     * Same as {@link CompletableFuture#allOf(CompletableFuture...)}, but it cancels the
-     * futures if returned future is canceled. The future returns the "worst" outcome,
-     * based on priority (see {@link #detmPriority(OperationOutcome)}).
+     * Similar to {@link CompletableFuture#allOf(CompletableFuture...)}.
      *
-     * @param futures futures for which to wait
-     * @return a future to cancel or await an outcome. If this future is canceled, then
-     *         all of the futures will be canceled
+     * @param futureMakers function to make a future. If the function returns
+     *        {@code null}, then no future is created for that function. On the other
+     *        hand, if the function throws an exception, then the previously created
+     *        functions are canceled and the exception is re-thrown
+     * @return a future to cancel or await an outcome, or {@code null} if no futures were
+     *         created. If this future is canceled, then all of the futures will be
+     *         canceled. Similarly, when this future completes, any incomplete futures
+     *         will be canceled
      */
     protected CompletableFuture<OperationOutcome> allOf(
-                    @SuppressWarnings("unchecked") CompletableFuture<OperationOutcome>... futures) {
-
-        if (futures.length == 1) {
-            return futures[0];
-        }
+                    List<Supplier<CompletableFuture<OperationOutcome>>> futureMakers) {
+        PipelineControllerFuture<OperationOutcome> controller = new PipelineControllerFuture<>();
 
-        final PipelineControllerFuture<OperationOutcome> controller = new PipelineControllerFuture<>();
-
-        attachFutures(controller, futures);
+        Queue<OperationOutcome> outcomes = new LinkedList<>();
 
-        OperationOutcome[] outcomes = new OperationOutcome[futures.length];
+        CompletableFuture<OperationOutcome>[] futures =
+                        attachFutures(controller, futureMakers, future -> future.thenApply(outcome -> {
+                            synchronized (outcomes) {
+                                outcomes.add(outcome);
+                            }
+                            return outcome;
+                        }));
 
-        @SuppressWarnings("rawtypes")
-        CompletableFuture[] futures2 = new CompletableFuture[futures.length];
+        if (futures.length == 0) {
+            // no futures were started
+            return null;
+        }
 
-        // record the outcomes of each future when it completes
-        for (int count = 0; count < futures2.length; ++count) {
-            final int count2 = count;
-            futures2[count] = futures[count].whenComplete((outcome2, thrown) -> outcomes[count2] = outcome2);
+        if (futures.length == 1) {
+            return futures[0];
         }
 
         // @formatter:off
-        CompletableFuture.allOf(futures2)
+        CompletableFuture.allOf(futures)
                         .thenApply(unused -> combineOutcomes(outcomes))
                         .whenCompleteAsync(controller.delayedComplete(), params.getExecutor());
         // @formatter:on
@@ -575,22 +595,62 @@ public abstract class OperationPartial implements Operation {
     }
 
     /**
-     * Attaches the given futures to the controller.
+     * Invokes the functions to create the futures and attaches them to the controller.
      *
      * @param controller master controller for all of the futures
-     * @param futures futures to be attached to the controller
-     */
-    private void attachFutures(PipelineControllerFuture<OperationOutcome> controller,
-                    @SuppressWarnings("unchecked") CompletableFuture<OperationOutcome>... futures) {
+     * @param futureMakers futures to be attached to the controller
+     * @param adorn function that "adorns" the future, possible adding onto its pipeline.
+     *        Returns the adorned future
+     * @return an array of futures, possibly zero-length. If the array is of size one,
+     *         then that one item should be returned instead of the controller
+     */
+    private CompletableFuture<OperationOutcome>[] attachFutures(PipelineControllerFuture<OperationOutcome> controller,
+                    List<Supplier<CompletableFuture<OperationOutcome>>> futureMakers,
+                    UnaryOperator<CompletableFuture<OperationOutcome>> adorn) {
+
+        if (futureMakers.isEmpty()) {
+            @SuppressWarnings("unchecked")
+            CompletableFuture<OperationOutcome>[] result = new CompletableFuture[0];
+            return result;
+        }
 
-        if (futures.length == 0) {
-            throw new IllegalArgumentException("empty list of futures");
+        // the last, unadorned future that is created
+        CompletableFuture<OperationOutcome> lastFuture = null;
+
+        List<CompletableFuture<OperationOutcome>> futures = new ArrayList<>(futureMakers.size());
+
+        // make each future
+        for (var maker : futureMakers) {
+            try {
+                CompletableFuture<OperationOutcome> future = maker.get();
+                if (future == null) {
+                    continue;
+                }
+
+                // propagate "stop" to the future
+                controller.add(future);
+
+                futures.add(adorn.apply(future));
+
+                lastFuture = future;
+
+            } catch (RuntimeException e) {
+                logger.warn("{}: exception creating 'future' for {}", getFullName(), params.getRequestId());
+                controller.cancel(false);
+                throw e;
+            }
         }
 
-        // attach each task
-        for (CompletableFuture<OperationOutcome> future : futures) {
-            controller.add(future);
+        @SuppressWarnings("unchecked")
+        CompletableFuture<OperationOutcome>[] result = new CompletableFuture[futures.size()];
+
+        if (result.length == 1) {
+            // special case - return the unadorned future
+            result[0] = lastFuture;
+            return result;
         }
+
+        return futures.toArray(result);
     }
 
     /**
@@ -599,15 +659,13 @@ public abstract class OperationPartial implements Operation {
      * @param outcomes outcomes to be examined
      * @return the combined outcome
      */
-    private OperationOutcome combineOutcomes(OperationOutcome[] outcomes) {
+    private OperationOutcome combineOutcomes(Queue<OperationOutcome> outcomes) {
 
         // identify the outcome with the highest priority
-        OperationOutcome outcome = outcomes[0];
+        OperationOutcome outcome = outcomes.remove();
         int priority = detmPriority(outcome);
 
-        // start with "1", as we've already dealt with "0"
-        for (int count = 1; count < outcomes.length; ++count) {
-            OperationOutcome outcome2 = outcomes[count];
+        for (OperationOutcome outcome2 : outcomes) {
             int priority2 = detmPriority(outcome2);
 
             if (priority2 > priority) {
@@ -656,72 +714,114 @@ public abstract class OperationPartial implements Operation {
     }
 
     /**
-     * Performs a task, after verifying that the controller is still running. Also checks
-     * that the previous outcome was successful, if specified.
+     * Performs a sequence of tasks, stopping if a task fails. A given task's future is
+     * not created until the previous task completes. The pipeline returns the outcome of
+     * the last task executed.
      *
-     * @param controller overall pipeline controller
-     * @param checkSuccess {@code true} to check the previous outcome, {@code false}
-     *        otherwise
-     * @param outcome outcome of the previous task
-     * @param task task to be performed
-     * @return the task, if everything checks out. Otherwise, it returns an incomplete
-     *         future and completes the controller instead
+     * @param futureMakers functions to make the futures
+     * @return a future to cancel the sequence or await the outcome
      */
-    // @formatter:off
-    protected CompletableFuture<OperationOutcome> doTask(
-                    PipelineControllerFuture<OperationOutcome> controller,
-                    boolean checkSuccess, OperationOutcome outcome,
-                    CompletableFuture<OperationOutcome> task) {
-        // @formatter:on
+    protected CompletableFuture<OperationOutcome> sequence(
+                    @SuppressWarnings("unchecked") Supplier<CompletableFuture<OperationOutcome>>... futureMakers) {
 
-        if (checkSuccess && !isSuccess(outcome)) {
-            /*
-             * must complete before canceling so that cancel() doesn't cause controller to
-             * complete
-             */
-            controller.complete(outcome);
-            task.cancel(false);
-            return new CompletableFuture<>();
+        return sequence(Arrays.asList(futureMakers));
+    }
+
+    /**
+     * Performs a sequence of tasks, stopping if a task fails. A given task's future is
+     * not created until the previous task completes. The pipeline returns the outcome of
+     * the last task executed.
+     *
+     * @param futureMakers functions to make the futures
+     * @return a future to cancel the sequence or await the outcome, or {@code null} if
+     *         there were no tasks to perform
+     */
+    protected CompletableFuture<OperationOutcome> sequence(
+                    List<Supplier<CompletableFuture<OperationOutcome>>> futureMakers) {
+
+        Queue<Supplier<CompletableFuture<OperationOutcome>>> queue = new ArrayDeque<>(futureMakers);
+
+        CompletableFuture<OperationOutcome> nextTask = getNextTask(queue);
+        if (nextTask == null) {
+            // no tasks
+            return null;
+        }
+
+        if (queue.isEmpty()) {
+            // only one task - just return it rather than wrapping it in a controller
+            return nextTask;
         }
 
-        return controller.wrap(task);
+        /*
+         * multiple tasks - need a controller to stop whichever task is currently
+         * executing
+         */
+        final PipelineControllerFuture<OperationOutcome> controller = new PipelineControllerFuture<>();
+        final Executor executor = params.getExecutor();
+
+        // @formatter:off
+        controller.wrap(nextTask)
+                    .thenComposeAsync(nextTaskOnSuccess(controller, queue), executor)
+                    .whenCompleteAsync(controller.delayedComplete(), executor);
+        // @formatter:on
+
+        return controller;
     }
 
     /**
-     * Performs a task, after verifying that the controller is still running. Also checks
-     * that the previous outcome was successful, if specified.
+     * Executes the next task in the queue, if the previous outcome was successful.
      *
-     * @param controller overall pipeline controller
-     * @param checkSuccess {@code true} to check the previous outcome, {@code false}
-     *        otherwise
-     * @param task function to start the task to be performed
-     * @return a function to perform the task. If everything checks out, then it returns
-     *         the task. Otherwise, it returns an incomplete future and completes the
-     *         controller instead
+     * @param controller pipeline controller
+     * @param taskQueue queue of tasks to be performed
+     * @return a future to execute the remaining tasks, or the current outcome, if it's a
+     *         failure, or if there are no more tasks
      */
-    // @formatter:off
-    protected Function<OperationOutcome, CompletableFuture<OperationOutcome>> doTask(
+    private Function<OperationOutcome, CompletableFuture<OperationOutcome>> nextTaskOnSuccess(
                     PipelineControllerFuture<OperationOutcome> controller,
-                    boolean checkSuccess,
-                    Function<OperationOutcome, CompletableFuture<OperationOutcome>> task) {
-        // @formatter:on
+                    Queue<Supplier<CompletableFuture<OperationOutcome>>> taskQueue) {
 
         return outcome -> {
-
-            if (!controller.isRunning()) {
-                return new CompletableFuture<>();
+            if (!isSuccess(outcome)) {
+                // return the failure
+                return CompletableFuture.completedFuture(outcome);
             }
 
-            if (checkSuccess && !isSuccess(outcome)) {
-                controller.complete(outcome);
-                return new CompletableFuture<>();
+            CompletableFuture<OperationOutcome> nextTask = getNextTask(taskQueue);
+            if (nextTask == null) {
+                // no tasks - just return the success
+                return CompletableFuture.completedFuture(outcome);
             }
 
-            return controller.wrap(task.apply(outcome));
+            // @formatter:off
+            return controller
+                        .wrap(nextTask)
+                        .thenComposeAsync(nextTaskOnSuccess(controller, taskQueue), params.getExecutor());
+            // @formatter:on
         };
     }
 
     /**
+     * Gets the next task from the queue, skipping those that are {@code null}.
+     *
+     * @param taskQueue task queue
+     * @return the next task, or {@code null} if the queue is now empty
+     */
+    private CompletableFuture<OperationOutcome> getNextTask(
+                    Queue<Supplier<CompletableFuture<OperationOutcome>>> taskQueue) {
+
+        Supplier<CompletableFuture<OperationOutcome>> maker;
+
+        while ((maker = taskQueue.poll()) != null) {
+            CompletableFuture<OperationOutcome> future = maker.get();
+            if (future != null) {
+                return future;
+            }
+        }
+
+        return null;
+    }
+
+    /**
      * Sets the start time of the operation and invokes the callback to indicate that the
      * operation has started. Does nothing if the pipeline has been stopped.
      * <p/>
@@ -809,6 +909,38 @@ public abstract class OperationPartial implements Operation {
         return (thrown instanceof TimeoutException);
     }
 
+    /**
+     * Logs a response. If the response is not of type, String, then it attempts to
+     * pretty-print it into JSON before logging.
+     *
+     * @param direction IN or OUT
+     * @param infra communication infrastructure on which it was published
+     * @param source source name (e.g., the URL or Topic name)
+     * @param response response to be logged
+     * @return the JSON text that was logged
+     */
+    public <T> String logMessage(EventType direction, CommInfrastructure infra, String source, T response) {
+        String json;
+        try {
+            if (response == null) {
+                json = null;
+            } else if (response instanceof String) {
+                json = response.toString();
+            } else {
+                json = makeCoder().encode(response, true);
+            }
+
+        } catch (CoderException e) {
+            String type = (direction == EventType.IN ? "response" : "request");
+            logger.warn("cannot pretty-print {}", type, e);
+            json = response.toString();
+        }
+
+        logger.info("[{}|{}|{}|]{}{}", direction, infra, source, NetLoggerUtil.SYSTEM_LS, json);
+
+        return json;
+    }
+
     // these may be overridden by subclasses or junit tests
 
     /**
@@ -841,4 +973,10 @@ public abstract class OperationPartial implements Operation {
     protected long getTimeoutMs(Integer timeoutSec) {
         return (timeoutSec == null ? 0 : TimeUnit.MILLISECONDS.convert(timeoutSec, TimeUnit.SECONDS));
     }
+
+    // these may be overridden by junit tests
+
+    protected Coder makeCoder() {
+        return coder;
+    }
 }
diff --git a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/impl/TopicPairActor.java b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/impl/TopicPairActor.java
deleted file mode 100644
index c3e1e5c4d..000000000
--- a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/impl/TopicPairActor.java
+++ /dev/null
@@ -1,112 +0,0 @@
-/*-
- * ============LICENSE_START=======================================================
- * ONAP
- * ================================================================================
- * Copyright (C) 2020 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.policy.controlloop.actorserviceprovider.impl;
-
-import java.util.Map;
-import java.util.TreeMap;
-import java.util.concurrent.ConcurrentHashMap;
-import java.util.function.Function;
-import org.apache.commons.lang3.tuple.Pair;
-import org.onap.policy.common.parameters.ValidationResult;
-import org.onap.policy.controlloop.actorserviceprovider.Util;
-import org.onap.policy.controlloop.actorserviceprovider.parameters.ParameterValidationRuntimeException;
-import org.onap.policy.controlloop.actorserviceprovider.parameters.TopicPairActorParams;
-import org.onap.policy.controlloop.actorserviceprovider.topic.TopicPair;
-import org.onap.policy.controlloop.actorserviceprovider.topic.TopicPairManager;
-
-/**
- * Actor that uses a topic pair. The actor's parameters must be a
- * {@link TopicPairActorParams}.
- */
-public class TopicPairActor extends ActorImpl implements TopicPairManager {
-
-    /**
-     * Maps a topic source and target name to its topic pair.
-     */
-    private final Map<Pair<String, String>, TopicPair> params2topic = new ConcurrentHashMap<>();
-
-
-    /**
-     * Constructs the object.
-     *
-     * @param name actor's name
-     */
-    public TopicPairActor(String name) {
-        super(name);
-    }
-
-    @Override
-    protected void doStart() {
-        params2topic.values().forEach(TopicPair::start);
-        super.doStart();
-    }
-
-    @Override
-    protected void doStop() {
-        params2topic.values().forEach(TopicPair::stop);
-        super.doStop();
-    }
-
-    @Override
-    protected void doShutdown() {
-        params2topic.values().forEach(TopicPair::shutdown);
-        params2topic.clear();
-        super.doShutdown();
-    }
-
-    @Override
-    public TopicPair getTopicPair(String source, String target) {
-        Pair<String, String> key = Pair.of(source, target);
-        return params2topic.computeIfAbsent(key, pair -> new TopicPair(source, target));
-    }
-
-    /**
-     * Translates the parameters to a {@link TopicPairActorParams} and then creates a
-     * function that will extract operator-specific parameters.
-     */
-    @Override
-    protected Function<String, Map<String, Object>> makeOperatorParameters(Map<String, Object> actorParameters) {
-        String actorName = getName();
-
-        TopicPairActorParams params = Util.translate(actorName, actorParameters, TopicPairActorParams.class);
-        ValidationResult result = params.validate(getName());
-        if (!result.isValid()) {
-            throw new ParameterValidationRuntimeException("invalid parameters", result);
-        }
-
-        // create a map of the default parameters
-        Map<String, Object> defaultParams = Util.translateToMap(getName(), params.getDefaults());
-        Map<String, Map<String, Object>> operations = params.getOperation();
-
-        return operationName -> {
-            Map<String, Object> specificParams = operations.get(operationName);
-            if (specificParams == null) {
-                return null;
-            }
-
-            // start with a copy of defaults and overlay with specific
-            Map<String, Object> subparams = new TreeMap<>(defaultParams);
-            subparams.putAll(specificParams);
-
-            return Util.translateToMap(getName() + "." + operationName, subparams);
-        };
-    }
-}
diff --git a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/parameters/BidirectionalTopicActorParams.java b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/parameters/BidirectionalTopicActorParams.java
new file mode 100644
index 000000000..291aeeb23
--- /dev/null
+++ b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/parameters/BidirectionalTopicActorParams.java
@@ -0,0 +1,57 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * ONAP
+ * ================================================================================
+ * Copyright (C) 2020 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.policy.controlloop.actorserviceprovider.parameters;
+
+import lombok.EqualsAndHashCode;
+import lombok.Getter;
+import lombok.Setter;
+import org.onap.policy.common.parameters.annotations.Min;
+
+/**
+ * Parameters used by Actors whose Operators use bidirectional topic.
+ */
+@Getter
+@Setter
+@EqualsAndHashCode(callSuper = true)
+public class BidirectionalTopicActorParams extends CommonActorParams {
+
+    /*
+     * Optional, default values that are used if missing from the operation-specific
+     * parameters.
+     */
+
+    /**
+     * Sink topic name to which requests should be published.
+     */
+    private String sinkTopic;
+
+    /**
+     * Source topic name, from which to read responses.
+     */
+    private String sourceTopic;
+
+    /**
+     * Amount of time, in seconds, to wait for the HTTP request to complete. The default
+     * is 90 seconds.
+     */
+    @Min(1)
+    private int timeoutSec = 90;
+}
diff --git a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/parameters/TopicPairParams.java b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/parameters/BidirectionalTopicParams.java
index 33fcf3052..cafca1fa6 100644
--- a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/parameters/TopicPairParams.java
+++ b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/parameters/BidirectionalTopicParams.java
@@ -29,31 +29,33 @@ import org.onap.policy.common.parameters.annotations.NotBlank;
 import org.onap.policy.common.parameters.annotations.NotNull;
 
 /**
- * Parameters used by Operators that use a pair of Topics, one to publish requests and the
- * other to receive responses.
+ * Parameters used by Operators that use a bidirectional topic.
  */
 @NotNull
 @NotBlank
 @Data
 @Builder(toBuilder = true)
-public class TopicPairParams {
+public class BidirectionalTopicParams {
 
     /**
-     * Source topic end point, from which to read responses.
+     * Sink topic name to which requests should be published.
      */
-    private String source;
+    private String sinkTopic;
 
     /**
-     * Name of the target topic end point to which requests should be published.
+     * Source topic name, from which to read responses.
      */
-    private String target;
+    private String sourceTopic;
 
     /**
-     * Amount of time, in seconds to wait for the response. The default is five minutes.
+     * Amount of time, in seconds to wait for the response.
+     * <p/>
+     * Note: this should NOT have a default value, as it receives its default value from
+     * {@link BidirectionalTopicActorParams}.
      */
     @Min(1)
-    @Builder.Default
-    private int timeoutSec = 300;
+    private int timeoutSec;
+
 
     /**
      * Validates the parameters.
diff --git a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/parameters/TopicPairActorParams.java b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/parameters/CommonActorParams.java
index 42a44ee9c..dc6f2b657 100644
--- a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/parameters/TopicPairActorParams.java
+++ b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/parameters/CommonActorParams.java
@@ -21,37 +21,57 @@
 package org.onap.policy.controlloop.actorserviceprovider.parameters;
 
 import java.util.Map;
-import lombok.Builder;
-import lombok.Data;
-import org.onap.policy.common.parameters.BeanValidationResult;
+import java.util.TreeMap;
+import java.util.function.Function;
+import lombok.EqualsAndHashCode;
+import lombok.Getter;
+import lombok.Setter;
 import org.onap.policy.common.parameters.BeanValidator;
 import org.onap.policy.common.parameters.ValidationResult;
-import org.onap.policy.common.parameters.annotations.NotBlank;
 import org.onap.policy.common.parameters.annotations.NotNull;
+import org.onap.policy.controlloop.actorserviceprovider.Util;
 
 /**
- * Parameters used by Actors whose Operators use a pair of Topics, one to publish requests
- * and the other to receive responses.
+ * Superclass for Actor parameters that have default values in "this" object, and
+ * operation-specific values in {@link #operation}.
  */
-@NotNull
-@NotBlank
-@Data
-@Builder
-public class TopicPairActorParams {
+@Getter
+@Setter
+@EqualsAndHashCode
+public class CommonActorParams {
 
     /**
-     * This contains the default parameters that are used when an operation doesn't
-     * specify them. Note: each operation to be used must still have an entry in
-     * {@link #operation}, even if it's empty. Otherwise, the given operation will not be
-     * started.
+     * Maps the operation name to its parameters.
      */
-    private TopicPairParams defaults;
+    @NotNull
+    protected Map<String, Map<String, Object>> operation;
+
 
     /**
-     * Maps an operation name to its individual parameters.
+     * Extracts a specific operation's parameters from "this".
+     *
+     * @param name name of the item containing "this"
+     * @return a function to extract an operation's parameters from "this". Note: the
+     *         returned function is not thread-safe
      */
-    private Map<String, Map<String, Object>> operation;
+    public Function<String, Map<String, Object>> makeOperationParameters(String name) {
+
+        Map<String, Object> defaultParams = Util.translateToMap(name, this);
+        defaultParams.remove("operation");
+
+        return operationName -> {
+            Map<String, Object> specificParams = operation.get(operationName);
+            if (specificParams == null) {
+                return null;
+            }
+
+            // start with a copy of defaults and overlay with specific
+            Map<String, Object> subparams = new TreeMap<>(defaultParams);
+            subparams.putAll(specificParams);
 
+            return Util.translateToMap(name + "." + operationName, subparams);
+        };
+    }
 
     /**
      * Validates the parameters.
@@ -60,7 +80,7 @@ public class TopicPairActorParams {
      * @return "this"
      * @throws IllegalArgumentException if the parameters are invalid
      */
-    public TopicPairActorParams doValidation(String name) {
+    public CommonActorParams doValidation(String name) {
         ValidationResult result = validate(name);
         if (!result.isValid()) {
             throw new ParameterValidationRuntimeException("invalid parameters", result);
@@ -77,17 +97,6 @@ public class TopicPairActorParams {
      * @return the validation result
      */
     public ValidationResult validate(String resultName) {
-        BeanValidationResult result = new BeanValidator().validateTop(resultName, this);
-
-        if (defaults != null) {
-            result.addResult(defaults.validate("defaults"));
-        }
-
-        // @formatter:off
-        result.validateMap("operation", operation,
-            (result2, entry) -> result2.validateNotNull(entry.getKey(), entry.getValue()));
-        // @formatter:on
-
-        return result;
+        return new BeanValidator().validateTop(resultName, this);
     }
 }
diff --git a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/parameters/HttpActorParams.java b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/parameters/HttpActorParams.java
index 275c8bc4e..d589e1d7e 100644
--- a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/parameters/HttpActorParams.java
+++ b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/parameters/HttpActorParams.java
@@ -20,26 +20,23 @@
 
 package org.onap.policy.controlloop.actorserviceprovider.parameters;
 
-import java.util.Map;
-import java.util.function.Function;
-import lombok.Data;
-import org.onap.policy.common.parameters.BeanValidationResult;
-import org.onap.policy.common.parameters.BeanValidator;
-import org.onap.policy.common.parameters.ValidationResult;
+import lombok.EqualsAndHashCode;
+import lombok.Getter;
+import lombok.Setter;
 import org.onap.policy.common.parameters.annotations.Min;
-import org.onap.policy.common.parameters.annotations.NotBlank;
-import org.onap.policy.common.parameters.annotations.NotNull;
-import org.onap.policy.controlloop.actorserviceprovider.Util;
 
 /**
- * Parameters used by Actors that connect to a server via HTTP. This contains the
- * parameters that are common to all of the operations. Only the path changes for each
- * operation, thus it includes a mapping from operation name to path.
+ * Parameters used by Actors that connect to a server via HTTP.
  */
-@Data
-@NotNull
-@NotBlank
-public class HttpActorParams {
+@Getter
+@Setter
+@EqualsAndHashCode(callSuper = true)
+public class HttpActorParams extends CommonActorParams {
+
+    /*
+     * Optional, default values that are used if missing from the operation-specific
+     * parameters.
+     */
 
     /**
      * Name of the HttpClient, as found in the HttpClientFactory.
@@ -47,66 +44,9 @@ public class HttpActorParams {
     private String clientName;
 
     /**
-     * Amount of time, in seconds to wait for the HTTP request to complete, where zero
-     * indicates that it should wait forever. The default is zero.
-     */
-    @Min(0)
-    private int timeoutSec = 0;
-
-    /**
-     * Maps the operation name to its URI path.
-     */
-    private Map<String, String> path;
-
-    /**
-     * Extracts a specific operation's parameters from "this".
-     *
-     * @param name name of the item containing "this"
-     * @return a function to extract an operation's parameters from "this". Note: the
-     *         returned function is not thread-safe
-     */
-    public Function<String, Map<String, Object>> makeOperationParameters(String name) {
-        HttpParams subparams = HttpParams.builder().clientName(getClientName()).timeoutSec(getTimeoutSec()).build();
-
-        return operation -> {
-            String subpath = path.get(operation);
-            if (subpath == null) {
-                return null;
-            }
-
-            subparams.setPath(subpath);
-            return Util.translateToMap(name + "." + operation, subparams);
-        };
-    }
-
-    /**
-     * Validates the parameters.
-     *
-     * @param name name of the object containing these parameters
-     * @return "this"
-     * @throws IllegalArgumentException if the parameters are invalid
+     * Amount of time, in seconds, to wait for the HTTP request to complete. The default
+     * is 90 seconds.
      */
-    public HttpActorParams doValidation(String name) {
-        ValidationResult result = validate(name);
-        if (!result.isValid()) {
-            throw new ParameterValidationRuntimeException("invalid parameters", result);
-        }
-
-        return this;
-    }
-
-    /**
-     * Validates the parameters.
-     *
-     * @param resultName name of the result
-     *
-     * @return the validation result
-     */
-    public ValidationResult validate(String resultName) {
-        BeanValidationResult result = new BeanValidator().validateTop(resultName, this);
-
-        result.validateMap("path", path, (result2, entry) -> result2.validateNotNull(entry.getKey(), entry.getValue()));
-
-        return result;
-    }
+    @Min(1)
+    private int timeoutSec = 90;
 }
diff --git a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/parameters/HttpParams.java b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/parameters/HttpParams.java
index 93711c032..2d3ab8b54 100644
--- a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/parameters/HttpParams.java
+++ b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/parameters/HttpParams.java
@@ -48,12 +48,13 @@ public class HttpParams {
     private String path;
 
     /**
-     * Amount of time, in seconds to wait for the HTTP request to complete, where zero
-     * indicates that it should wait forever. The default is zero.
+     * Amount of time, in seconds, to wait for the HTTP request to complete.
+     * <p/>
+     * Note: this should NOT have a default value, as it receives its default value from
+     * {@link HttpActorParams}.
      */
-    @Min(0)
-    @Builder.Default
-    private int timeoutSec = 0;
+    @Min(1)
+    private int timeoutSec;
 
 
     /**
diff --git a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/topic/BidirectionalTopicHandler.java b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/topic/BidirectionalTopicHandler.java
new file mode 100644
index 000000000..30ee1e2d0
--- /dev/null
+++ b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/topic/BidirectionalTopicHandler.java
@@ -0,0 +1,79 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * ONAP
+ * ================================================================================
+ * Copyright (C) 2020 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.policy.controlloop.actorserviceprovider.topic;
+
+import java.util.List;
+import org.onap.policy.common.endpoints.event.comm.client.BidirectionalTopicClient;
+import org.onap.policy.common.endpoints.event.comm.client.BidirectionalTopicClientException;
+
+/**
+ * Handler for a bidirectional topic, supporting both publishing and forwarding of
+ * incoming messages.
+ */
+public class BidirectionalTopicHandler extends BidirectionalTopicClient {
+
+    /**
+     * Listener that will be attached to the topic to receive responses.
+     */
+    private final TopicListenerImpl listener = new TopicListenerImpl();
+
+
+    /**
+     * Constructs the object.
+     *
+     * @param sinkTopic sink topic name
+     * @param sourceTopic source topic name
+     * @throws BidirectionalTopicClientException if an error occurs
+     */
+    public BidirectionalTopicHandler(String sinkTopic, String sourceTopic) throws BidirectionalTopicClientException {
+        super(sinkTopic, sourceTopic);
+    }
+
+    /**
+     * Starts listening on the source topic(s).
+     */
+    public void start() {
+        getSource().register(listener);
+    }
+
+    /**
+     * Stops listening on the source topic(s).
+     */
+    public void stop() {
+        getSource().unregister(listener);
+    }
+
+    /**
+     * Stops listening on the source topic(s) and clears all of the forwarders.
+     */
+    public void shutdown() {
+        stop();
+        listener.shutdown();
+    }
+
+    public Forwarder addForwarder(SelectorKey... keys) {
+        return listener.addForwarder(keys);
+    }
+
+    public Forwarder addForwarder(List<SelectorKey> keys) {
+        return listener.addForwarder(keys);
+    }
+}
diff --git a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/topic/TopicPairManager.java b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/topic/BidirectionalTopicManager.java
index c351f95f6..10411875a 100644
--- a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/topic/TopicPairManager.java
+++ b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/topic/BidirectionalTopicManager.java
@@ -21,17 +21,17 @@
 package org.onap.policy.controlloop.actorserviceprovider.topic;
 
 /**
- * Manages topic pairs.
+ * Manages bidirectional topics.
  */
 @FunctionalInterface
-public interface TopicPairManager {
+public interface BidirectionalTopicManager {
 
     /**
-     * Gets the topic pair for the given parameters, creating one if it does not exist.
+     * Gets the topic handler for the given parameters, creating one if it does not exist.
      *
-     * @param source source topic name
-     * @param target target topic name
-     * @return the topic pair associated with the given source and target topics
+     * @param sinkTopic sink topic name
+     * @param sourceTopic source topic name
+     * @return the topic handler associated with the given sink and source topic names
      */
-    TopicPair getTopicPair(String source, String target);
+    BidirectionalTopicHandler getTopicHandler(String sinkTopic, String sourceTopic);
 }
diff --git a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/topic/Forwarder.java b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/topic/Forwarder.java
index 8e9109c9e..2d98b66fc 100644
--- a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/topic/Forwarder.java
+++ b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/topic/Forwarder.java
@@ -24,8 +24,7 @@ import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
-import org.onap.policy.common.endpoints.event.comm.Topic.CommInfrastructure;
-import org.onap.policy.common.endpoints.utils.PropertyUtils.TriConsumer;
+import java.util.function.BiConsumer;
 import org.onap.policy.common.utils.coder.StandardCoderObject;
 import org.onap.policy.controlloop.actorserviceprovider.Util;
 import org.slf4j.Logger;
@@ -43,7 +42,7 @@ public class Forwarder {
      * Maps a set of field values to one or more listeners.
      */
     // @formatter:off
-    private final Map<List<String>, Map<TriConsumer<CommInfrastructure, String, StandardCoderObject>, String>>
+    private final Map<List<String>, Map<BiConsumer<String, StandardCoderObject>, String>>
                 values2listeners = new ConcurrentHashMap<>();
     // @formatter:on
 
@@ -68,13 +67,13 @@ public class Forwarder {
      * @param values field values of interest, in one-to-one correspondence with the keys
      * @param listener listener to register
      */
-    public void register(List<String> values, TriConsumer<CommInfrastructure, String, StandardCoderObject> listener) {
+    public void register(List<String> values, BiConsumer<String, StandardCoderObject> listener) {
         if (keys.size() != values.size()) {
             throw new IllegalArgumentException("key/value mismatch");
         }
 
         values2listeners.compute(values, (key, listeners) -> {
-            Map<TriConsumer<CommInfrastructure, String, StandardCoderObject>, String> map = listeners;
+            Map<BiConsumer<String, StandardCoderObject>, String> map = listeners;
             if (map == null) {
                 map = new ConcurrentHashMap<>();
             }
@@ -90,7 +89,7 @@ public class Forwarder {
      * @param values field values of interest, in one-to-one correspondence with the keys
      * @param listener listener to unregister
      */
-    public void unregister(List<String> values, TriConsumer<CommInfrastructure, String, StandardCoderObject> listener) {
+    public void unregister(List<String> values, BiConsumer<String, StandardCoderObject> listener) {
         values2listeners.computeIfPresent(values, (key, listeners) -> {
             listeners.remove(listener);
             return (listeners.isEmpty() ? null : listeners);
@@ -100,11 +99,10 @@ public class Forwarder {
     /**
      * Processes a message, forwarding it to the appropriate listeners, if any.
      *
-     * @param infra communication infrastructure on which the response was received
      * @param textMessage original text message that was received
      * @param scoMessage decoded text message
      */
-    public void onMessage(CommInfrastructure infra, String textMessage, StandardCoderObject scoMessage) {
+    public void onMessage(String textMessage, StandardCoderObject scoMessage) {
         // extract the key values from the message
         List<String> values = new ArrayList<>(keys.size());
         for (SelectorKey key : keys) {
@@ -121,8 +119,7 @@ public class Forwarder {
         }
 
         // get the listeners for this set of values
-        Map<TriConsumer<CommInfrastructure, String, StandardCoderObject>, String> listeners =
-                        values2listeners.get(values);
+        Map<BiConsumer<String, StandardCoderObject>, String> listeners = values2listeners.get(values);
         if (listeners == null) {
             // no listeners for this particular list of values
             return;
@@ -130,9 +127,9 @@ public class Forwarder {
 
 
         // forward the message to each listener
-        for (TriConsumer<CommInfrastructure, String, StandardCoderObject> listener : listeners.keySet()) {
+        for (BiConsumer<String, StandardCoderObject> listener : listeners.keySet()) {
             try {
-                listener.accept(infra, textMessage, scoMessage);
+                listener.accept(textMessage, scoMessage);
             } catch (RuntimeException e) {
                 logger.warn("exception thrown by listener {}", Util.ident(listener), e);
             }
diff --git a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/topic/TopicListenerImpl.java b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/topic/TopicListenerImpl.java
index eb805ca5d..fcb463518 100644
--- a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/topic/TopicListenerImpl.java
+++ b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/topic/TopicListenerImpl.java
@@ -98,7 +98,7 @@ public class TopicListenerImpl implements TopicListener {
          * them all take a crack at it.
          */
         for (Forwarder forwarder : selector2forwarder.values()) {
-            forwarder.onMessage(infra, message, object);
+            forwarder.onMessage(message, object);
         }
     }
 }
diff --git a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/topic/TopicPair.java b/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/topic/TopicPair.java
deleted file mode 100644
index c0cfe2571..000000000
--- a/models-interactions/model-actors/actorServiceProvider/src/main/java/org/onap/policy/controlloop/actorserviceprovider/topic/TopicPair.java
+++ /dev/null
@@ -1,122 +0,0 @@
-/*-
- * ============LICENSE_START=======================================================
- * ONAP
- * ================================================================================
- * Copyright (C) 2020 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.policy.controlloop.actorserviceprovider.topic;
-
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.List;
-import lombok.Getter;
-import org.onap.policy.common.endpoints.event.comm.Topic.CommInfrastructure;
-import org.onap.policy.common.endpoints.event.comm.TopicEndpoint;
-import org.onap.policy.common.endpoints.event.comm.TopicEndpointManager;
-import org.onap.policy.common.endpoints.event.comm.TopicSink;
-import org.onap.policy.common.endpoints.event.comm.TopicSource;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-/**
- * A pair of topics, one of which is used to publish requests and the other to receive
- * responses.
- */
-public class TopicPair extends TopicListenerImpl {
-    private static final Logger logger = LoggerFactory.getLogger(TopicPair.class);
-
-    @Getter
-    private final String source;
-
-    @Getter
-    private final String target;
-
-    private final List<TopicSink> publishers;
-    private final List<TopicSource> subscribers;
-
-    /**
-     * Constructs the object.
-     *
-     * @param source source topic name
-     * @param target target topic name
-     */
-    public TopicPair(String source, String target) {
-        this.source = source;
-        this.target = target;
-
-        publishers = getTopicEndpointManager().getTopicSinks(target);
-        if (publishers.isEmpty()) {
-            throw new IllegalArgumentException("no sinks for topic: " + target);
-        }
-
-        subscribers = getTopicEndpointManager().getTopicSources(Arrays.asList(source));
-        if (subscribers.isEmpty()) {
-            throw new IllegalArgumentException("no sources for topic: " + source);
-        }
-    }
-
-    /**
-     * Starts listening on the source topic(s).
-     */
-    public void start() {
-        subscribers.forEach(topic -> topic.register(this));
-    }
-
-    /**
-     * Stops listening on the source topic(s).
-     */
-    public void stop() {
-        subscribers.forEach(topic -> topic.unregister(this));
-    }
-
-    /**
-     * Stops listening on the source topic(s) and clears all of the forwarders.
-     */
-    @Override
-    public void shutdown() {
-        stop();
-        super.shutdown();
-    }
-
-    /**
-     * Publishes a message to the target topic.
-     *
-     * @param message message to be published
-     * @return a list of the infrastructures on which it was published
-     */
-    public List<CommInfrastructure> publish(String message) {
-        List<CommInfrastructure> infrastructures = new ArrayList<>(publishers.size());
-
-        for (TopicSink topic : publishers) {
-            try {
-                topic.send(message);
-                infrastructures.add(topic.getTopicCommInfrastructure());
-
-            } catch (RuntimeException e) {
-                logger.warn("cannot publish to {}:{}", topic.getTopicCommInfrastructure(), target, e);
-            }
-        }
-
-        return infrastructures;
-    }
-
-    // these may be overridden by junit tests
-
-    protected TopicEndpoint getTopicEndpointManager() {
-        return TopicEndpointManager.getManager();
-    }
-}