Implement http participant in CLAMP

Issue-ID: POLICY-3449
Signed-off-by: zrrmmua <ramesh.murugan.iyer@est.tech>
Change-Id: Ibfe23a6e98fb760a930b6080dc2291113b3cb4fa

14 files changed, 1119 insertions, 0 deletions

diff --git a/participant/participant-impl/participant-impl-http/src/main/java/org/onap/policy/clamp/controlloop/participant/http/Application.java b/participant/participant-impl/participant-impl-http/src/main/java/org/onap/policy/clamp/controlloop/participant/http/Application.java
new file mode 100644
index 000000000..dc36392f7
--- /dev/null
+++ b/participant/participant-impl/participant-impl-http/src/main/java/org/onap/policy/clamp/controlloop/participant/http/Application.java
@@ -0,0 +1,40 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2021 Nordix Foundation.
+ * ================================================================================
+ * 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.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.clamp.controlloop.participant.http;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+/**
+ * Starter.
+ *
+ */
+@SpringBootApplication
+public class Application {
+    /**
+     * Main class.
+     *
+     * @param args args
+     */
+    public static void main(String[] args) {
+        SpringApplication.run(Application.class, args);
+    }
+}
diff --git a/participant/participant-impl/participant-impl-http/src/main/java/org/onap/policy/clamp/controlloop/participant/http/config/ParticipantConfig.java b/participant/participant-impl/participant-impl-http/src/main/java/org/onap/policy/clamp/controlloop/participant/http/config/ParticipantConfig.java
new file mode 100644
index 000000000..ce013a765
--- /dev/null
+++ b/participant/participant-impl/participant-impl-http/src/main/java/org/onap/policy/clamp/controlloop/participant/http/config/ParticipantConfig.java
@@ -0,0 +1,43 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2021 Nordix Foundation.
+ * ================================================================================
+ * 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.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.clamp.controlloop.participant.http.config;
+
+import org.onap.policy.clamp.controlloop.participant.http.main.handler.ControlLoopElementHandler;
+import org.onap.policy.clamp.controlloop.participant.intermediary.api.ParticipantIntermediaryApi;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.annotation.Configuration;
+
+@Configuration
+public class ParticipantConfig {
+
+    /**
+     * Register ControlLoopElementListener.
+     *
+     * @param intermediaryApi the ParticipantIntermediaryApi
+     * @param clElementHandler the ControlLoop Element Handler
+     */
+    @Autowired
+    public void registerControlLoopElementListener(ParticipantIntermediaryApi intermediaryApi,
+            ControlLoopElementHandler clElementHandler) {
+        intermediaryApi.registerControlLoopElementListener(clElementHandler);
+        clElementHandler.setIntermediaryApi(intermediaryApi);
+    }
+}
diff --git a/participant/participant-impl/participant-impl-http/src/main/java/org/onap/policy/clamp/controlloop/participant/http/main/exception/HttpWebClientException.java b/participant/participant-impl/participant-impl-http/src/main/java/org/onap/policy/clamp/controlloop/participant/http/main/exception/HttpWebClientException.java
new file mode 100644
index 000000000..b10af884c
--- /dev/null
+++ b/participant/participant-impl/participant-impl-http/src/main/java/org/onap/policy/clamp/controlloop/participant/http/main/exception/HttpWebClientException.java
@@ -0,0 +1,31 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2021 Nordix Foundation.
+ * ================================================================================
+ * 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.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.clamp.controlloop.participant.http.main.exception;
+
+
+import org.springframework.web.reactive.function.client.WebClientResponseException;
+
+public class HttpWebClientException extends WebClientResponseException {
+
+    public HttpWebClientException(int statusCode, String statusText) {
+        super(statusCode, statusText, null, null, null);
+    }
+}
diff --git a/participant/participant-impl/participant-impl-http/src/main/java/org/onap/policy/clamp/controlloop/participant/http/main/handler/ControlLoopElementHandler.java b/participant/participant-impl/participant-impl-http/src/main/java/org/onap/policy/clamp/controlloop/participant/http/main/handler/ControlLoopElementHandler.java
new file mode 100644
index 000000000..67948a95c
--- /dev/null
+++ b/participant/participant-impl/participant-impl-http/src/main/java/org/onap/policy/clamp/controlloop/participant/http/main/handler/ControlLoopElementHandler.java
@@ -0,0 +1,148 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2021 Nordix Foundation.
+ * ================================================================================
+ * 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.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.clamp.controlloop.participant.http.main.handler;
+
+import java.io.Closeable;
+import java.io.IOException;
+import java.lang.invoke.MethodHandles;
+import java.util.Map;
+import java.util.Set;
+import java.util.UUID;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import javax.validation.ConstraintViolation;
+import javax.validation.Validation;
+import javax.validation.ValidationException;
+import lombok.Getter;
+import lombok.Setter;
+import org.apache.commons.lang3.tuple.Pair;
+import org.onap.policy.clamp.controlloop.models.controlloop.concepts.ControlLoopElement;
+import org.onap.policy.clamp.controlloop.models.controlloop.concepts.ControlLoopOrderedState;
+import org.onap.policy.clamp.controlloop.models.controlloop.concepts.ControlLoopState;
+import org.onap.policy.clamp.controlloop.participant.http.main.models.ConfigRequest;
+import org.onap.policy.clamp.controlloop.participant.http.main.webclient.ClHttpClient;
+import org.onap.policy.clamp.controlloop.participant.intermediary.api.ControlLoopElementListener;
+import org.onap.policy.clamp.controlloop.participant.intermediary.api.ParticipantIntermediaryApi;
+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.models.base.PfModelException;
+import org.onap.policy.models.tosca.authorative.concepts.ToscaConceptIdentifier;
+import org.onap.policy.models.tosca.authorative.concepts.ToscaNodeTemplate;
+import org.onap.policy.models.tosca.authorative.concepts.ToscaServiceTemplate;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.stereotype.Component;
+
+/**
+ * This class handles implementation of controlLoopElement updates.
+ */
+@Component
+public class ControlLoopElementHandler implements ControlLoopElementListener, Closeable {
+
+    private static final Coder CODER = new StandardCoder();
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(MethodHandles.lookup().lookupClass());
+
+    private ExecutorService executor = Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors());
+
+    private Map<ToscaConceptIdentifier, Pair<Integer, String>> restResponseMap = new ConcurrentHashMap<>();
+
+    @Setter
+    private ParticipantIntermediaryApi intermediaryApi;
+
+    /**
+     * Handle controlLoopElement statistics.
+     *
+     * @param controlLoopElementId controlloop element id
+     */
+    @Override
+    public void handleStatistics(UUID controlLoopElementId) throws PfModelException {
+        // Implementation not needed for http participant
+
+    }
+
+    /**
+     * Handle a control loop element state change.
+     *
+     * @param controlLoopElementId the ID of the control loop element
+     * @param currentState         the current state of the control loop element
+     * @param newState             the state to which the control loop element is changing to
+     * @throws PfModelException in case of a model exception
+     */
+    @Override
+    public void controlLoopElementStateChange(UUID controlLoopElementId, ControlLoopState currentState,
+                                              ControlLoopOrderedState newState) throws PfModelException {
+        // Implementation not needed for http participant
+    }
+
+    /**
+     * Callback method to handle an update on a control loop element.
+     *
+     * @param element the information on the control loop element
+     * @param controlLoopDefinition toscaServiceTemplate
+     */
+    @Override
+    public void controlLoopElementUpdate(ControlLoopElement element, ToscaServiceTemplate controlLoopDefinition) {
+
+        for (Map.Entry<String, ToscaNodeTemplate> nodeTemplate : controlLoopDefinition.getToscaTopologyTemplate()
+            .getNodeTemplates().entrySet()) {
+            // Fetching the node template of corresponding CL element
+            if (element.getDefinition().getName().equals(nodeTemplate.getKey())) {
+                try {
+                    var configRequest = CODER.convert(nodeTemplate.getValue().getProperties(), ConfigRequest.class);
+                    Set<ConstraintViolation<ConfigRequest>> violations = Validation.buildDefaultValidatorFactory()
+                        .getValidator().validate(configRequest);
+                    if (violations.isEmpty()) {
+                        invokeHttpClient(configRequest);
+                    } else {
+                        LOGGER.error("Violations found in the config request parameters: {}", violations);
+                        throw new ValidationException("Constraint violations in the config request");
+                    }
+                } catch (CoderException | ValidationException e) {
+                    LOGGER.error("Error invoking the http request for the config ", e);
+                }
+            }
+        }
+    }
+
+    /**
+     * Invoke a runnable thread to execute http requests.
+     * @param configRequest ConfigRequest
+     */
+    public void invokeHttpClient(ConfigRequest configRequest) {
+        // Invoke runnable thread to execute https requests of all config entities
+        executor.execute(new ClHttpClient(configRequest, restResponseMap));
+    }
+
+    /**
+     * Closes this stream and releases any system resources associated
+     * with it. If the stream is already closed then invoking this
+     * method has no effect.
+     *
+     * @throws IOException if an I/O error occurs
+     */
+    @Override
+    public void close() throws IOException {
+        executor.shutdown();
+    }
+}
diff --git a/participant/participant-impl/participant-impl-http/src/main/java/org/onap/policy/clamp/controlloop/participant/http/main/models/ConfigRequest.java b/participant/participant-impl/participant-impl-http/src/main/java/org/onap/policy/clamp/controlloop/participant/http/main/models/ConfigRequest.java
new file mode 100644
index 000000000..87cab88a7
--- /dev/null
+++ b/participant/participant-impl/participant-impl-http/src/main/java/org/onap/policy/clamp/controlloop/participant/http/main/models/ConfigRequest.java
@@ -0,0 +1,51 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2021 Nordix Foundation.
+ * ================================================================================
+ * 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.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.clamp.controlloop.participant.http.main.models;
+
+import java.util.List;
+import java.util.Map;
+import javax.validation.Valid;
+import javax.validation.constraints.Min;
+import javax.validation.constraints.NotBlank;
+import javax.validation.constraints.NotNull;
+import javax.ws.rs.DefaultValue;
+import lombok.AllArgsConstructor;
+import lombok.Data;
+
+@Data
+@AllArgsConstructor
+public class ConfigRequest {
+
+    @NotBlank
+    private String baseUrl;
+
+    @NotNull
+    private Map<String, String> httpHeaders;
+
+    @NotNull
+    @Valid
+    private List<ConfigurationEntity> configurationEntities;
+
+    @Min(value = 1)
+    @DefaultValue("20")
+    private int uninitializedToPassiveTimeout;
+
+}
diff --git a/participant/participant-impl/participant-impl-http/src/main/java/org/onap/policy/clamp/controlloop/participant/http/main/models/ConfigurationEntity.java b/participant/participant-impl/participant-impl-http/src/main/java/org/onap/policy/clamp/controlloop/participant/http/main/models/ConfigurationEntity.java
new file mode 100644
index 000000000..8703a9d21
--- /dev/null
+++ b/participant/participant-impl/participant-impl-http/src/main/java/org/onap/policy/clamp/controlloop/participant/http/main/models/ConfigurationEntity.java
@@ -0,0 +1,40 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2021 Nordix Foundation.
+ * ================================================================================
+ * 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.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.clamp.controlloop.participant.http.main.models;
+
+import java.util.List;
+import javax.validation.Valid;
+import javax.validation.constraints.NotNull;
+import lombok.AllArgsConstructor;
+import lombok.Data;
+import org.onap.policy.models.tosca.authorative.concepts.ToscaConceptIdentifier;
+
+@Data
+@AllArgsConstructor
+public class ConfigurationEntity {
+
+    @NotNull
+    private ToscaConceptIdentifier configurationEntityId;
+
+    @NotNull
+    @Valid
+    private List<RestParams> restSequence;
+}
diff --git a/participant/participant-impl/participant-impl-http/src/main/java/org/onap/policy/clamp/controlloop/participant/http/main/models/RestParams.java b/participant/participant-impl/participant-impl-http/src/main/java/org/onap/policy/clamp/controlloop/participant/http/main/models/RestParams.java
new file mode 100644
index 000000000..fc4e02897
--- /dev/null
+++ b/participant/participant-impl/participant-impl-http/src/main/java/org/onap/policy/clamp/controlloop/participant/http/main/models/RestParams.java
@@ -0,0 +1,54 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2021 Nordix Foundation.
+ * ================================================================================
+ * 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.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.clamp.controlloop.participant.http.main.models;
+
+import java.util.Map;
+import javax.validation.constraints.Max;
+import javax.validation.constraints.Min;
+import javax.validation.constraints.NotNull;
+import lombok.AllArgsConstructor;
+import lombok.Data;
+import org.onap.policy.models.tosca.authorative.concepts.ToscaConceptIdentifier;
+
+@Data
+@AllArgsConstructor
+public class RestParams {
+
+    @NotNull
+    private ToscaConceptIdentifier restRequestId;
+
+    @NotNull
+    private String httpMethod;
+
+    @NotNull
+    private String path;
+
+    @Min(100)
+    @Max(599)
+    private int expectedResponse;
+
+    private Map<String, Object> pathParams;
+
+    private Map<String, String> queryParams;
+
+    private String body;
+
+}
diff --git a/participant/participant-impl/participant-impl-http/src/main/java/org/onap/policy/clamp/controlloop/participant/http/main/webclient/ClHttpClient.java b/participant/participant-impl/participant-impl-http/src/main/java/org/onap/policy/clamp/controlloop/participant/http/main/webclient/ClHttpClient.java
new file mode 100644
index 000000000..0e0ea557e
--- /dev/null
+++ b/participant/participant-impl/participant-impl-http/src/main/java/org/onap/policy/clamp/controlloop/participant/http/main/webclient/ClHttpClient.java
@@ -0,0 +1,135 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2021 Nordix Foundation.
+ * ================================================================================
+ * 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.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.clamp.controlloop.participant.http.main.webclient;
+
+import java.lang.invoke.MethodHandles;
+import java.time.Duration;
+import java.util.Map;
+import java.util.Objects;
+import org.apache.commons.lang3.tuple.ImmutablePair;
+import org.apache.commons.lang3.tuple.Pair;
+import org.onap.policy.clamp.controlloop.participant.http.main.exception.HttpWebClientException;
+import org.onap.policy.clamp.controlloop.participant.http.main.models.ConfigRequest;
+import org.onap.policy.clamp.controlloop.participant.http.main.models.ConfigurationEntity;
+import org.onap.policy.clamp.controlloop.participant.http.main.models.RestParams;
+import org.onap.policy.models.tosca.authorative.concepts.ToscaConceptIdentifier;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpMethod;
+import org.springframework.web.reactive.function.BodyInserters;
+import org.springframework.web.reactive.function.client.WebClient;
+import org.springframework.web.util.UriComponentsBuilder;
+import reactor.core.publisher.Mono;
+
+public class ClHttpClient implements Runnable {
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(MethodHandles.lookup().lookupClass());
+
+    private final ConfigRequest configRequest;
+
+    private Map<ToscaConceptIdentifier, Pair<Integer, String>> responseMap;
+
+    /**
+     * Constructor.
+     */
+    public ClHttpClient(ConfigRequest configRequest, Map<ToscaConceptIdentifier, Pair<Integer, String>> responseMap) {
+        this.configRequest = configRequest;
+        this.responseMap = responseMap;
+    }
+
+    /**
+     * Runnable to execute http requests.
+     */
+    @Override
+    public void run() {
+
+        var webClient = WebClient.builder()
+            .baseUrl(configRequest.getBaseUrl())
+            .defaultHeaders(httpHeaders -> httpHeaders.addAll(createHeaders(configRequest)))
+            .build();
+
+        for (ConfigurationEntity configurationEntity : configRequest.getConfigurationEntities()) {
+            LOGGER.info("Executing http requests for the config entity {}",
+                configurationEntity.getConfigurationEntityId());
+
+            executeRequest(webClient, configurationEntity);
+        }
+    }
+
+    private void executeRequest(WebClient client, ConfigurationEntity configurationEntity)  {
+
+        // Iterate the sequence of http requests
+        for (RestParams request: configurationEntity.getRestSequence()) {
+            String response = null;
+            try {
+                var httpMethod = Objects.requireNonNull(HttpMethod.resolve(request.getHttpMethod()));
+                var uri = createUriString(request);
+                LOGGER.info("Executing HTTP request: {} for the Rest request id: {}", httpMethod,
+                        request.getRestRequestId());
+
+                response = client.method(httpMethod)
+                    .uri(uri)
+                    .body(request.getBody() == null ? BodyInserters.empty()
+                        : BodyInserters.fromValue(request.getBody()))
+                    .exchangeToMono(clientResponse ->
+                        clientResponse.statusCode().value() == request.getExpectedResponse()
+                            ? clientResponse.bodyToMono(String.class)
+                            : Mono.error(new HttpWebClientException(clientResponse.statusCode().value(),
+                                clientResponse.bodyToMono(String.class).toString())))
+                    .block(Duration.ofMillis(configRequest.getUninitializedToPassiveTimeout() * 1000L));
+
+                LOGGER.info("HTTP response for the {} request : {}", httpMethod, response);
+                responseMap.put(request.getRestRequestId(), new ImmutablePair<>(request.getExpectedResponse(),
+                    response));
+
+            } catch (HttpWebClientException ex) {
+                LOGGER.error("Error occurred on the HTTP request ", ex);
+                responseMap.put(request.getRestRequestId(), new ImmutablePair<>(ex.getStatusCode().value(),
+                     ex.getResponseBodyAsString()));
+            }
+        }
+    }
+
+    private HttpHeaders createHeaders(ConfigRequest request) {
+        var headers = new HttpHeaders();
+        for (Map.Entry<String, String> entry: request.getHttpHeaders().entrySet()) {
+            headers.add(entry.getKey(), entry.getValue());
+        }
+        return headers;
+    }
+
+    private String createUriString(RestParams restParams) {
+        var uriComponentsBuilder = UriComponentsBuilder.fromUriString(restParams.getPath());
+        // Add path params if present
+        if (restParams.getPathParams() != null) {
+            uriComponentsBuilder.uriVariables(restParams.getPathParams());
+        }
+        // Add query params if present
+        if (restParams.getQueryParams() != null) {
+            for (Map.Entry<String, String> entry : restParams.getQueryParams().entrySet()) {
+                uriComponentsBuilder.queryParam(entry.getKey(), entry.getValue());
+            }
+        }
+        return uriComponentsBuilder.build().toUriString();
+    }
+
+}
diff --git a/participant/participant-impl/participant-impl-http/src/main/resources/config/application.yaml b/participant/participant-impl/participant-impl-http/src/main/resources/config/application.yaml
new file mode 100644
index 000000000..1fd528458
--- /dev/null
+++ b/participant/participant-impl/participant-impl-http/src/main/resources/config/application.yaml
@@ -0,0 +1,27 @@
+participant:
+  intermediaryParameters:
+    reportingTimeInterval: 120000
+    description: Participant Description
+    participantId:
+      name: HttpParticipant0
+      version: 1.0.0
+    participantType:
+      name: org.onap.k8s.controlloop.HttpControlLoopParticipant
+      version: 2.3.4
+    clampControlLoopTopics:
+      topicSources:
+        - topic: POLICY-CLRUNTIME-PARTICIPANT
+          servers:
+            - ${topicServer:message-router}
+          topicCommInfrastructure: dmaap
+          fetchTimeout: 15000
+      topicSinks:
+        - topic: POLICY-CLRUNTIME-PARTICIPANT
+          servers:
+            - ${topicServer:message-router}
+          topicCommInfrastructure: dmaap
+
+        - topic: POLICY-NOTIFICATION
+          servers:
+            - ${topicServer:message-router}
+          topicCommInfrastructure: dmaap
diff --git a/participant/participant-impl/participant-impl-http/src/test/java/handler/ClElementHandlerTest.java b/participant/participant-impl/participant-impl-http/src/test/java/handler/ClElementHandlerTest.java
new file mode 100644
index 000000000..10b8103cb
--- /dev/null
+++ b/participant/participant-impl/participant-impl-http/src/test/java/handler/ClElementHandlerTest.java
@@ -0,0 +1,63 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2021 Nordix Foundation.
+ * ================================================================================
+ * 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.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package handler;
+
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.Mockito.doNothing;
+
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.InjectMocks;
+import org.mockito.Spy;
+import org.onap.policy.clamp.controlloop.models.controlloop.concepts.ControlLoopElement;
+import org.onap.policy.clamp.controlloop.participant.http.main.handler.ControlLoopElementHandler;
+import org.onap.policy.common.utils.coder.CoderException;
+import org.onap.policy.models.tosca.authorative.concepts.ToscaServiceTemplate;
+import org.springframework.test.context.junit.jupiter.SpringExtension;
+import utils.CommonTestData;
+import utils.ToscaUtils;
+
+@ExtendWith(SpringExtension.class)
+class ClElementHandlerTest {
+
+    @InjectMocks
+    @Spy
+    private ControlLoopElementHandler controlLoopElementHandler = new ControlLoopElementHandler();
+
+    private CommonTestData commonTestData = new CommonTestData();
+
+    private static ToscaServiceTemplate serviceTemplate;
+
+    @BeforeAll
+    static void init() throws CoderException {
+        serviceTemplate = ToscaUtils.readControlLoopFromTosca();
+    }
+
+    @Test
+    void test_ControlLoopElementUpdate() {
+        doNothing().when(controlLoopElementHandler).invokeHttpClient(any());
+        ControlLoopElement element = commonTestData.getControlLoopElement();
+        assertDoesNotThrow(() -> controlLoopElementHandler
+            .controlLoopElementUpdate(element, serviceTemplate));
+    }
+}
diff --git a/participant/participant-impl/participant-impl-http/src/test/java/utils/CommonTestData.java b/participant/participant-impl/participant-impl-http/src/test/java/utils/CommonTestData.java
new file mode 100644
index 000000000..84957edfa
--- /dev/null
+++ b/participant/participant-impl/participant-impl-http/src/test/java/utils/CommonTestData.java
@@ -0,0 +1,146 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2021 Nordix Foundation.
+ * ================================================================================
+ * 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.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package utils;
+
+import java.util.List;
+import java.util.Map;
+import java.util.UUID;
+import org.onap.policy.clamp.controlloop.models.controlloop.concepts.ControlLoopElement;
+import org.onap.policy.clamp.controlloop.models.controlloop.concepts.ControlLoopOrderedState;
+import org.onap.policy.clamp.controlloop.participant.http.main.models.ConfigurationEntity;
+import org.onap.policy.clamp.controlloop.participant.http.main.models.RestParams;
+import org.onap.policy.common.utils.coder.Coder;
+import org.onap.policy.common.utils.coder.StandardCoder;
+import org.onap.policy.models.tosca.authorative.concepts.ToscaConceptIdentifier;
+
+public class CommonTestData {
+
+    private static final Coder CODER = new StandardCoder();
+    private static final String TEST_KEY_NAME = "org.onap.domain.database.Http_PMSHMicroserviceControlLoopElement";
+
+
+    /**
+     * Get a controlLoop Element.
+     * @return controlLoopElement object
+     */
+    public ControlLoopElement getControlLoopElement() {
+        ControlLoopElement element = new ControlLoopElement();
+        element.setId(UUID.randomUUID());
+        element.setDefinition(new ToscaConceptIdentifier(TEST_KEY_NAME, "1.0.1"));
+        element.setOrderedState(ControlLoopOrderedState.PASSIVE);
+        return element;
+    }
+
+    /**
+     * Get query params.
+     * @return Map of query params
+     */
+    public Map<String, String> getQueryParams() {
+        return Map.of("name", "dummy", "version", "1.0");
+    }
+
+    /**
+     * Get path params.
+     * @return Map of path params
+     */
+    public Map<String, Object> getPathParams() {
+        return Map.of("id", "123", "name", "dummy");
+    }
+
+    /**
+     * Rest params with GET request.
+     * @return RestParams obj
+     */
+    public RestParams restParamsWithGet() {
+        return new RestParams(
+            new ToscaConceptIdentifier("getRequest", "1.0"),
+            "GET",
+            "get",
+            200,
+            null,
+            getQueryParams(),
+            null
+        );
+    }
+
+    /**
+     * Rest params with POST request.
+     * @return RestParams obj
+     */
+    public RestParams restParamsWithPost() {
+        return new RestParams(
+            new ToscaConceptIdentifier("postRequest", "1.0"),
+            "POST",
+            "post",
+            200,
+            null,
+            getQueryParams(),
+            "Test body"
+        );
+    }
+
+    /**
+     * Rest params with POST request.
+     * @return RestParams obj
+     */
+    public RestParams restParamsWithInvalidPost() {
+        return new RestParams(
+            new ToscaConceptIdentifier("postRequest", "1.0"),
+            "POST",
+            "post/{id}/{name}",
+            200,
+            getPathParams(),
+            getQueryParams(),
+            "Test body"
+        );
+    }
+
+    /**
+     * Get invalid configuration entity.
+     * @return ConfigurationEntity obj
+     */
+    public ConfigurationEntity getInvalidConfigurationEntity() {
+        return new ConfigurationEntity(
+            new ToscaConceptIdentifier("config1", "1.0.1"),
+            List.of(restParamsWithGet(), restParamsWithInvalidPost())
+        );
+    }
+
+    /**
+     * Get configuration entity.
+     * @return ConfigurationEntity obj
+     */
+    public ConfigurationEntity getConfigurationEntity() {
+        return new ConfigurationEntity(
+            new ToscaConceptIdentifier("config1", "1.0.1"),
+            List.of(restParamsWithGet(), restParamsWithPost())
+        );
+    }
+
+    /**
+     * Get headers for config request.
+     * @return Map of headers
+     */
+    public Map<String, String> getHeaders() {
+        return  Map.of("Content-Type", "application/json", "Accept", "application/json");
+    }
+
+}
diff --git a/participant/participant-impl/participant-impl-http/src/test/java/utils/ToscaUtils.java b/participant/participant-impl/participant-impl-http/src/test/java/utils/ToscaUtils.java
new file mode 100644
index 000000000..cf71248c3
--- /dev/null
+++ b/participant/participant-impl/participant-impl-http/src/test/java/utils/ToscaUtils.java
@@ -0,0 +1,48 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2021 Nordix Foundation.
+ * ================================================================================
+ * 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.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package utils;
+
+import org.onap.policy.common.utils.coder.YamlJsonTranslator;
+import org.onap.policy.common.utils.resources.ResourceUtils;
+import org.onap.policy.models.tosca.authorative.concepts.ToscaServiceTemplate;
+
+/**
+ * Util class for Test scope.
+ */
+public class ToscaUtils {
+
+    private static final YamlJsonTranslator yamlTranslator = new YamlJsonTranslator();
+    private static final String TOSCA_TEMPLATE_YAML = "src/test/resources/HttpParticipantConfig.yaml";
+
+
+    /**
+     * Read a service template yaml.
+     * @return ToscaServiceTemplate
+     */
+    public static ToscaServiceTemplate readControlLoopFromTosca() {
+        return serializeControlLoopYaml(TOSCA_TEMPLATE_YAML);
+    }
+
+    private static ToscaServiceTemplate serializeControlLoopYaml(String controlLoopFilePath) {
+        String controlLoopString = ResourceUtils.getResourceAsString(controlLoopFilePath);
+        return yamlTranslator.fromYaml(controlLoopString, ToscaServiceTemplate.class);
+    }
+}
diff --git a/participant/participant-impl/participant-impl-http/src/test/java/webclient/ClHttpClientTest.java b/participant/participant-impl/participant-impl-http/src/test/java/webclient/ClHttpClientTest.java
new file mode 100644
index 000000000..411974a04
--- /dev/null
+++ b/participant/participant-impl/participant-impl-http/src/test/java/webclient/ClHttpClientTest.java
@@ -0,0 +1,85 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2021 Nordix Foundation.
+ * ================================================================================
+ * 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.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package webclient;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import org.apache.commons.lang3.tuple.Pair;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.onap.policy.clamp.controlloop.participant.http.main.models.ConfigRequest;
+import org.onap.policy.clamp.controlloop.participant.http.main.models.ConfigurationEntity;
+import org.onap.policy.clamp.controlloop.participant.http.main.webclient.ClHttpClient;
+import org.onap.policy.models.tosca.authorative.concepts.ToscaConceptIdentifier;
+import org.springframework.test.context.junit.jupiter.SpringExtension;
+import utils.CommonTestData;
+
+@ExtendWith(SpringExtension.class)
+class ClHttpClientTest {
+
+    private CommonTestData commonTestData = new CommonTestData();
+
+    private String testBaseUrl = "https://httpbin.org";
+
+    private Map<ToscaConceptIdentifier, Pair<Integer, String>> responseMap = new HashMap<>();
+
+
+    @Test
+    void test_validRequest() {
+        //Add valid rest requests POST, GET
+        ConfigurationEntity configurationEntity = commonTestData.getConfigurationEntity();
+
+        Map<String, String> headers = commonTestData.getHeaders();
+        ConfigRequest configRequest = new ConfigRequest(testBaseUrl, headers,
+            List.of(configurationEntity), 10);
+
+        ClHttpClient client = new ClHttpClient(configRequest, responseMap);
+        assertDoesNotThrow(client::run);
+        assertThat(responseMap).hasSize(2).containsKey(commonTestData
+            .restParamsWithGet().getRestRequestId());
+
+        Pair<Integer, String> restResponseMap = responseMap.get(commonTestData
+            .restParamsWithGet().getRestRequestId());
+        assertThat(restResponseMap.getKey()).isEqualTo(200);
+    }
+
+    @Test
+    void test_invalidRequest() {
+        //Add rest requests Invalid POST, Valid GET
+        ConfigurationEntity configurationEntity = commonTestData.getInvalidConfigurationEntity();
+
+        Map<String, String> headers = commonTestData.getHeaders();
+        ConfigRequest configRequest = new ConfigRequest(testBaseUrl, headers,
+            List.of(configurationEntity), 10);
+
+        ClHttpClient client = new ClHttpClient(configRequest, responseMap);
+        assertDoesNotThrow(client::run);
+        assertThat(responseMap).hasSize(2).containsKey(commonTestData
+            .restParamsWithGet().getRestRequestId());
+        Pair<Integer, String> response = responseMap
+            .get(commonTestData.restParamsWithInvalidPost().getRestRequestId());
+        assertThat(response.getKey()).isEqualTo(404);
+    }
+}
diff --git a/participant/participant-impl/participant-impl-http/src/test/resources/HttpParticipantConfig.yaml b/participant/participant-impl/participant-impl-http/src/test/resources/HttpParticipantConfig.yaml
new file mode 100644
index 000000000..43d0c269c
--- /dev/null
+++ b/participant/participant-impl/participant-impl-http/src/test/resources/HttpParticipantConfig.yaml
@@ -0,0 +1,208 @@
+# ============LICENSE_START=======================================================
+# Copyright (C) 2021 Nordix Foundation.
+# ================================================================================
+# 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.
+#
+# SPDX-License-Identifier: Apache-2.0
+# ============LICENSE_END=========================================================
+tosca_definitions_version: tosca_simple_yaml_1_3
+data_types:
+  onap.datatypes.ToscaConceptIdentifier:
+    derived_from: tosca.datatypes.Root
+    properties:
+      name:
+        type: string
+        required: true
+      version:
+        type: string
+        required: true
+
+  org.onap.datatypes.policy.clamp.controlloop.httpControlLoopElement.RestRequest:
+    version: 1.0.0
+    derived_from: tosca.datatypes.Root
+    properties:
+      restRequestId:
+        type:  onap.datatypes.ToscaConceptIdentifier
+        typeVersion: 1.0.0
+        required: true
+        description: The name and version of a REST request to be sent to a REST endpoint
+      httpMethod:
+        type: string
+        required: true
+        constraints:
+          - valid_values: [POST, PUT, GET, DELETE]
+        description: The REST method to use
+      path:
+        type: string
+        required: true
+        description: The path of the REST request relative to the base URL
+      body:
+        type: string
+        required: false
+        description: The body of the REST request for PUT and POST requests
+      expectedResponse:
+        type: integer
+        required: true
+        constraints:
+          - in_range: [100, 599]
+        description: THe expected HTTP status code for the REST request
+    org.onap.datatypes.policy.clamp.controlloop.httpControlLoopElement.ConfigurationEntity:
+      version: 1.0.0
+      derived_from: tosca.datatypes.Root
+      properties:
+        configurationEntityId:
+          type:  onap.datatypes.ToscaConceptIdentifier
+          typeVersion: 1.0.0
+          required: true
+          description: The name and version of a Configuration Entity to be handled by the HTTP Control Loop Element
+        restSequence:
+          type: list
+          entry_schema:
+            type: org.onap.datatypes.policy.clamp.controlloop.httpControlLoopElement.RestRequest
+            typeVersion: 1.0.0
+          description: A sequence of REST commands to send to the REST endpoint
+
+
+node_types:
+  org.onap.policy.clamp.controlloop.Participant:
+    version: 1.0.1
+    derived_from: tosca.nodetypes.Root
+    properties:
+      provider:
+        type: string
+        requred: false
+  org.onap.policy.clamp.controlloop.ControlLoopElement:
+    version: 1.0.1
+    derived_from: tosca.nodetypes.Root
+    properties:
+      provider:
+        type: string
+        requred: false
+      participant_id:
+        type: onap.datatypes.ToscaConceptIdentifier
+        requred: true
+  org.onap.policy.clamp.controlloop.ControlLoop:
+    version: 1.0.1
+    derived_from: tosca.nodetypes.Root
+    properties:
+      provider:
+        type: string
+        requred: false
+      elements:
+        type: list
+        required: true
+        entry_schema:
+          type: onap.datatypes.ToscaConceptIdentifier
+  org.onap.policy.clamp.controlloop.HttpControlLoopElement:
+    version: 1.0.1
+    derived_from: org.onap.policy.clamp.controlloop.ControlLoopElement
+    properties:
+      baseUrl:
+        type: string
+        required: true
+        description: The base URL to be prepended to each path, identifies the host for the REST endpoints.
+      httpHeaders:
+        type: map
+        required: false
+        entry_schema:
+          type: string
+        description: HTTP headers to send on REST requests
+      configurationEntities:
+        type: map
+        required: true
+        entry_schema:
+          type: org.onap.datatypes.policy.clamp.controlloop.httpControlLoopElement.ConfigurationEntity
+          typeVersion: 1.0.0
+        description: The connfiguration entities the Control Loop Element is managing and their associated REST requests
+topology_template:
+  node_templates:
+    org.onap.k8s.controlloop.HttpControlLoopParticipant:
+      version: 2.3.4
+      type: org.onap.policy.clamp.controlloop.Participant
+      type_version: 1.0.1
+      description: Participant for Http requests
+      properties:
+        provider: ONAP
+
+    org.onap.domain.database.Http_PMSHMicroserviceControlLoopElement:
+      # Http config for PMSH.
+      version: 1.2.3
+      type: org.onap.policy.clamp.controlloop.HttpControlLoopElement
+      type_version: 1.0.1
+      description: Control loop element for the http requests of PMSH microservice
+      properties:
+        provider: ONAP
+        participant_id:
+          name: org.onap.controlloop.HttpControlLoopParticipant
+          version: 2.3.4
+        uninitializedToPassiveTimeout: 180
+        baseUrl: https://httpbin.org
+        httpHeaders:
+          Content-Type: application/json
+        configurationEntities:
+          - configurationEntityId:
+              name: entity1
+              version: 1.0.1
+            restSequence:
+              - restRequestId:
+                  name: request1
+                  version: 1.0.1
+                httpMethod: POST
+                path: post
+                body: '{"name":"ob1","port_type"}'
+                expectedResponse: 200
+
+              - restRequestId:
+                  name: request1
+                  version: 1.0.1
+                httpMethod: GET
+                path: get
+                expectedResponse: 200
+
+          # Rest path with path params and query params
+          - configurationEntityId:
+              name: entity2
+              version: 1.0.1
+            restSequence:
+              - restRequestId:
+                  name: request1
+                  version: 1.0.1
+                httpMethod: POST
+                path: post/{id}/{name}
+                pathParams:
+                  id: 123
+                  name: dummyName
+                body: this is a test body
+                expectedResponse: 200
+
+              - restRequestId:
+                  name: request1
+                  version: 1.0.1
+                httpMethod: GET
+                path: get
+                queryParams:
+                  id: 123
+                  name: dummyName
+                expectedResponse: 200
+
+
+    org.onap.domain.sample.GenericK8s_ControlLoopDefinition:
+      version: 1.2.3
+      type: org.onap.policy.clamp.controlloop.ControlLoop
+      type_version: 1.0.0
+      description: Control loop for HTTP request
+      properties:
+        provider: ONAP
+        elements:
+          - name: org.onap.domain.database.Http_PMSHMicroserviceControlLoopElement
+            version: 1.2.3