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diff --git a/src/main/java/org/onap/policy/clamp/policy/PolicyEngineServices.java b/src/main/java/org/onap/policy/clamp/policy/PolicyEngineServices.java
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+/*-
+ * ============LICENSE_START=======================================================
+ * ONAP CLAMP
+ * ================================================================================
+ * Copyright (C) 2020-2021 AT&T Intellectual Property. All rights
+ *                             reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * 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.clamp.policy;
+
+import com.att.eelf.configuration.EELFLogger;
+import com.att.eelf.configuration.EELFManager;
+import java.util.LinkedHashMap;
+import java.util.Map;
+import org.apache.camel.CamelContext;
+import org.apache.camel.Exchange;
+import org.apache.camel.builder.ExchangeBuilder;
+import org.onap.policy.clamp.clds.config.ClampProperties;
+import org.onap.policy.clamp.clds.sdc.controller.installer.BlueprintMicroService;
+import org.onap.policy.clamp.clds.util.JsonUtils;
+import org.onap.policy.clamp.loop.template.PolicyModel;
+import org.onap.policy.clamp.loop.template.PolicyModelsService;
+import org.onap.policy.models.pdp.concepts.PdpGroups;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Component;
+import org.yaml.snakeyaml.DumperOptions;
+import org.yaml.snakeyaml.Yaml;
+
+
+/**
+ * The class implements the communication with the Policy Engine to retrieve
+ * policy models (tosca). It mainly delegates the physical calls to Camel
+ * engine.
+ * It supports a retry mechanism for these calls, configurations can be specified in the
+ * application.properties "policy.retry.interval"(default 0) and "policy.retry.limit"(default 1).
+ */
+@Component
+public class PolicyEngineServices {
+    private final CamelContext camelContext;
+
+    private final PolicyModelsService policyModelsService;
+
+    private static final EELFLogger logger = EELFManager.getInstance().getLogger(PolicyEngineServices.class);
+    private static int retryInterval = 0;
+    private static int retryLimit = 1;
+
+    public static final String POLICY_RETRY_INTERVAL = "policy.retry.interval";
+    public static final String POLICY_RETRY_LIMIT = "policy.retry.limit";
+
+    /**
+     * Default constructor.
+     *
+     * @param camelContext        Camel context bean
+     * @param clampProperties     ClampProperties bean
+     * @param policyModelsService policyModel service
+     */
+    @Autowired
+    public PolicyEngineServices(CamelContext camelContext, ClampProperties clampProperties,
+                                PolicyModelsService policyModelsService) {
+        this.camelContext = camelContext;
+        this.policyModelsService = policyModelsService;
+        if (clampProperties.getStringValue(POLICY_RETRY_LIMIT) != null) {
+            retryLimit = Integer.parseInt(clampProperties.getStringValue(POLICY_RETRY_LIMIT));
+        }
+        if (clampProperties.getStringValue(POLICY_RETRY_INTERVAL) != null) {
+            retryInterval = Integer.parseInt(clampProperties.getStringValue(POLICY_RETRY_INTERVAL));
+        }
+    }
+
+    /**
+     * This method query Policy engine and create a PolicyModel object with type and version.
+     * If the policy already exist in the db it returns the existing one.
+     *
+     * @param policyType    The policyType id
+     * @param policyVersion The policy version of that type
+     * @return A PolicyModel created from policyEngine data or null if nothing is found on policyEngine
+     */
+    public PolicyModel createPolicyModelFromPolicyEngine(String policyType, String policyVersion) {
+        PolicyModel policyModelFound = policyModelsService.getPolicyModel(policyType, policyVersion);
+        if (policyModelFound == null) {
+            String policyTosca = this.downloadOnePolicyToscaModel(policyType, policyVersion);
+            if (policyTosca != null && !policyTosca.isEmpty()) {
+                return policyModelsService.savePolicyModelInNewTransaction(
+                        new PolicyModel(policyType, policyTosca, policyVersion));
+            } else {
+                logger.error("Policy not found in the Policy Engine, returning null: " + policyType
+                        + "/" + policyVersion);
+                return null;
+            }
+        } else {
+            logger.info("Skipping policy model download as it exists already in the database " + policyType
+                    + "/" + policyVersion);
+            return policyModelFound;
+        }
+    }
+
+    /**
+     * This method query Policy engine and create a PolicyModel object with type and version.
+     *
+     * @param microService microservice object instance
+     * @return A PolicyModel created from policyEngine data
+     */
+    public PolicyModel createPolicyModelFromPolicyEngine(BlueprintMicroService microService) {
+        return createPolicyModelFromPolicyEngine(microService.getModelType(), microService.getModelVersion());
+    }
+
+    /**
+     * This method synchronize the clamp database and the policy engine.
+     * So it creates the required PolicyModel.
+     */
+    public void synchronizeAllPolicies() {
+        LinkedHashMap<String, Object> loadedYaml;
+        loadedYaml = new Yaml().load(downloadAllPolicyModels());
+        if (loadedYaml == null || loadedYaml.isEmpty()) {
+            logger.warn("getAllPolicyType yaml returned by policy engine could not be decoded, as it's null or empty");
+            return;
+        }
+
+        LinkedHashMap<String, Object> policyTypesMap = (LinkedHashMap<String, Object>) loadedYaml
+                .get("policy_types");
+        policyTypesMap.forEach((key, value) ->
+                this.createPolicyModelFromPolicyEngine(key,
+                        ((String) ((LinkedHashMap<String, Object>) value).get("version"))));
+    }
+
+    /**
+     * This method can be used to download all policy types + data types defined in
+     * policy engine.
+     *
+     * @return A yaml containing all policy Types and all data types
+     */
+    public String downloadAllPolicyModels() {
+        return callCamelRoute(ExchangeBuilder.anExchange(camelContext).build(), "direct:get-all-policy-models",
+                "Get all policies models");
+    }
+
+    /**
+     * This method can be used to download a policy tosca model on the engine.
+     *
+     * @param policyType    The policy type (id)
+     * @param policyVersion The policy version
+     * @return A string with the whole policy tosca model
+     */
+    public String downloadOnePolicyToscaModel(String policyType, String policyVersion) {
+        logger.info("Downloading the policy tosca model " + policyType + "/" + policyVersion);
+        DumperOptions options = new DumperOptions();
+        options.setDefaultScalarStyle(DumperOptions.ScalarStyle.PLAIN);
+        options.setIndent(4);
+        options.setPrettyFlow(true);
+        options.setDefaultFlowStyle(DumperOptions.FlowStyle.BLOCK);
+        Yaml yamlParser = new Yaml(options);
+        String responseBody = callCamelRoute(
+                ExchangeBuilder.anExchange(camelContext).withProperty("policyModelName", policyType)
+                        .withProperty("policyModelVersion", policyVersion).build(), "direct:get-policy-tosca-model",
+                "Get one policy");
+
+        if (responseBody == null || responseBody.isEmpty()) {
+            logger.warn("getPolicyToscaModel returned by policy engine could not be decoded, as it's null or empty");
+            return null;
+        }
+
+        return yamlParser.dump((Map<String, Object>) yamlParser.load(responseBody));
+    }
+
+    /**
+     * This method can be used to download all Pdp Groups data from policy engine.
+     */
+    public void downloadPdpGroups() {
+        String responseBody =
+                callCamelRoute(ExchangeBuilder.anExchange(camelContext).build(), "direct:get-all-pdp-groups",
+                        "Get Pdp Groups");
+
+        if (responseBody == null || responseBody.isEmpty()) {
+            logger.warn("getPdpGroups returned by policy engine could not be decoded, as it's null or empty");
+            return;
+        }
+
+        policyModelsService.updatePdpGroupInfo(JsonUtils.GSON.fromJson(responseBody, PdpGroups.class));
+    }
+
+    private String callCamelRoute(Exchange exchange, String camelFlow, String logMsg) {
+        for (int i = 0; i < retryLimit; i++) {
+            Exchange exchangeResponse = camelContext.createProducerTemplate().send(camelFlow, exchange);
+            if (Integer.valueOf(200).equals(exchangeResponse.getIn().getHeader("CamelHttpResponseCode"))) {
+                return (String) exchangeResponse.getIn().getBody();
+            } else {
+                logger.info(logMsg + " query " + retryInterval + "ms before retrying ...");
+                // wait for a while and try to connect to DCAE again
+                try {
+                    Thread.sleep(retryInterval);
+                } catch (InterruptedException e) {
+                    Thread.currentThread().interrupt();
+                }
+            }
+        }
+        return "";
+    }
+}