1 files changed, 277 insertions, 0 deletions
diff --git a/feature-healthcheck/src/main/java/org/onap/policy/drools/healthcheck/HealthCheck.java b/feature-healthcheck/src/main/java/org/onap/policy/drools/healthcheck/HealthCheck.java
new file mode 100644
index 00000000..0e4ed792
--- /dev/null
+++ b/feature-healthcheck/src/main/java/org/onap/policy/drools/healthcheck/HealthCheck.java
@@ -0,0 +1,277 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * feature-healthcheck
+ * ================================================================================
+ * Copyright (C) 2017 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.drools.healthcheck;
+
+import java.util.ArrayList;
+import java.util.Properties;
+
+import javax.ws.rs.core.Response;
+
+import org.onap.policy.drools.http.client.HttpClient;
+import org.onap.policy.drools.http.server.HttpServletServer;
+import org.onap.policy.drools.persistence.SystemPersistence;
+import org.onap.policy.drools.properties.Startable;
+import org.onap.policy.drools.system.PolicyEngine;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Healthcheck
+ */
+public interface HealthCheck extends Startable {
+	
+	/**
+	 * Healthcheck Report
+	 */
+	public static class Report {
+		/**
+		 * Named Entity in the report
+		 */
+		public String name;
+		
+		/**
+		 * URL queried
+		 */
+		public String url;
+		
+		/**
+		 * healthy?
+		 */
+		public boolean healthy;
+		
+		/**
+		 * return code
+		 */
+		public int code;
+		
+		/**
+		 * Message from remote entity
+		 */
+		public String message;
+		
+		@Override
+		public String toString() {
+			StringBuilder builder = new StringBuilder();
+			builder.append("Report [name=");
+			builder.append(name);
+			builder.append(", url=");
+			builder.append(url);
+			builder.append(", healthy=");
+			builder.append(healthy);
+			builder.append(", code=");
+			builder.append(code);
+			builder.append(", message=");
+			builder.append(message);
+			builder.append("]");
+			return builder.toString();
+		}
+	}
+	
+	/**
+	 * Report aggregation
+	 */
+	public static class Reports {
+		public boolean healthy;
+		public ArrayList<Report> details = new ArrayList<>();
+		
+		@Override
+		public String toString() {
+			StringBuilder builder = new StringBuilder();
+			builder.append("Reports [healthy=");
+			builder.append(healthy);
+			builder.append(", details=");
+			builder.append(details);
+			builder.append("]");
+			return builder.toString();
+		}
+	}
+	
+	/**
+	 * perform a healthcheck
+	 * @return a report
+	 */
+	public Reports healthCheck();
+
+	/**
+	 * Healthcheck Monitor
+	 */
+	public static final HealthCheck monitor = new HealthCheckMonitor();
+}
+
+/**
+ * Healthcheck Monitor
+ */
+class HealthCheckMonitor implements HealthCheck {
+
+	/**
+	 * Logger
+	 */
+	private static Logger logger = LoggerFactory.getLogger(HealthCheckMonitor.class);
+	
+	/**
+	 * attached http servers
+	 */
+	protected volatile ArrayList<HttpServletServer> servers = new ArrayList<>();
+	
+	/**
+	 * attached http clients
+	 */
+	protected volatile ArrayList<HttpClient> clients = new ArrayList<>();
+	
+	/**
+	 * healthcheck configuration
+	 */
+	protected volatile Properties healthCheckProperties = null; 
+	
+	/**
+	 * {@inheritDoc}
+	 */
+	public Reports healthCheck() {	
+		Reports reports = new Reports();
+		reports.healthy = PolicyEngine.manager.isAlive();
+		
+		HealthCheck.Report engineReport = new Report();
+		engineReport.healthy = PolicyEngine.manager.isAlive();
+		engineReport.name = "PDP-D";
+		engineReport.url = "self";
+		engineReport.code = (PolicyEngine.manager.isAlive()) ? 200 : 500;
+		engineReport.message = (PolicyEngine.manager.isAlive()) ? "alive" : "not alive";
+		reports.details.add(engineReport);
+		
+		for (HttpClient client : clients) {
+			HealthCheck.Report report = new Report();
+			report.name = client.getName();
+			report.url = client.getBaseUrl();
+			report.healthy = true;
+			try {
+				Response response = client.get();
+				report.code = response.getStatus();
+				if (report.code != 200) {
+					report.healthy = false;
+					reports.healthy = false;
+				}
+					
+				try {
+					report.message = HttpClient.getBody(response, String.class);
+				} catch (Exception e) {
+					logger.warn("{}: cannot get body from http-client {}", this, client, e);
+				}
+			} catch (Exception e) {
+				report.healthy = false;
+				reports.healthy = false;
+			}
+			reports.details.add(report);
+		}
+		return reports;
+	}
+	
+	/**
+	 * {@inheritDoc}
+	 */
+	@Override
+	public boolean start() throws IllegalStateException {
+		
+		try {
+			this.healthCheckProperties = SystemPersistence.manager.getProperties(HealthCheckFeature.CONFIGURATION_PROPERTIES_NAME);
+			this.servers = HttpServletServer.factory.build(healthCheckProperties);
+			this.clients = HttpClient.factory.build(healthCheckProperties);
+			
+			for (HttpServletServer server : servers) {
+				try {
+					server.start();
+				} catch (Exception e) {
+					logger.warn("{}: cannot start http-server {}", this, server, e);
+				}
+			}
+		} catch (Exception e) {
+			return false;
+		}
+		
+		return true;
+	}
+
+	/**
+	 * {@inheritDoc}
+	 */
+	@Override
+	public boolean stop() throws IllegalStateException {
+		
+		for (HttpServletServer server : servers) {
+			try {
+				server.stop();
+			} catch (Exception e) {
+				logger.warn("{}: cannot stop http-server {}", this, server, e);
+			}
+		}
+		
+		for (HttpClient client : clients) {
+			try {
+				client.stop();
+			} catch (Exception e) {
+				logger.warn("{}: cannot stop http-client {}", this, client, e);
+			}
+		}
+		
+		return true;
+	}
+
+	/**
+	 * {@inheritDoc}
+	 */
+	@Override
+	public void shutdown() throws IllegalStateException {
+		this.stop();
+	}
+
+	/**
+	 * {@inheritDoc}
+	 */
+	@Override
+	public synchronized boolean isAlive() {
+		return this.healthCheckProperties != null;
+	}
+	
+	/**
+	 * @return list of attached Http Servers
+	 */
+	public ArrayList<HttpServletServer> getServers() {
+		return this.servers;
+	}
+	
+	/**
+	 * @return list of attached Http Clients
+	 */
+	public ArrayList<HttpClient> getClients() {
+		return this.clients;
+	}
+
+	@Override
+	public String toString() {
+		StringBuilder builder = new StringBuilder();
+		builder.append("HealthCheckMonitor [servers=");
+		builder.append(servers);
+		builder.append(", clients=");
+		builder.append(clients);
+		builder.append("]");
+		return builder.toString();
+	}
+	
+}