feature-healthcheck/src/main/java/org/onap/policy/drools/healthcheck/HealthCheck.java

   1 /*-
   2  * ============LICENSE_START=======================================================
   3  * feature-healthcheck
   4  * ================================================================================
   5  * Copyright (C) 2017 AT&T Intellectual Property. All rights reserved.
   6  * ================================================================================
   7  * Licensed under the Apache License, Version 2.0 (the "License");
   8  * you may not use this file except in compliance with the License.
   9  * You may obtain a copy of the License at
  10  *
  11  *      http://www.apache.org/licenses/LICENSE-2.0
  12  *
  13  * Unless required by applicable law or agreed to in writing, software
  14  * distributed under the License is distributed on an "AS IS" BASIS,
  15  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  16  * See the License for the specific language governing permissions and
  17  * limitations under the License.
  18  * ============LICENSE_END=========================================================
  19  */
  20
  21 package org.onap.policy.drools.healthcheck;
  22
  23 import java.util.ArrayList;
  24 import java.util.Properties;
  25
  26 import javax.ws.rs.core.Response;
  27
  28 import org.onap.policy.drools.http.client.HttpClient;
  29 import org.onap.policy.drools.http.server.HttpServletServer;
  30 import org.onap.policy.drools.persistence.SystemPersistence;
  31 import org.onap.policy.drools.properties.Startable;
  32 import org.onap.policy.drools.system.PolicyEngine;
  33 import org.slf4j.Logger;
  34 import org.slf4j.LoggerFactory;
  35
  36 /**
  37  * Healthcheck
  38  */
  39 public interface HealthCheck extends Startable {
  40
  41         /**
  42          * Healthcheck Report
  43          */
  44         public static class Report {
  45                 /**
  46                  * Named Entity in the report
  47                  */
  48                 public String name;
  49
  50                 /**
  51                  * URL queried
  52                  */
  53                 public String url;
  54
  55                 /**
  56                  * healthy?
  57                  */
  58                 public boolean healthy;
  59
  60                 /**
  61                  * return code
  62                  */
  63                 public int code;
  64
  65                 /**
  66                  * Message from remote entity
  67                  */
  68                 public String message;
  69
  70                 @Override
  71                 public String toString() {
  72                         StringBuilder builder = new StringBuilder();
  73                         builder.append("Report [name=");
  74                         builder.append(name);
  75                         builder.append(", url=");
  76                         builder.append(url);
  77                         builder.append(", healthy=");
  78                         builder.append(healthy);
  79                         builder.append(", code=");
  80                         builder.append(code);
  81                         builder.append(", message=");
  82                         builder.append(message);
  83                         builder.append("]");
  84                         return builder.toString();
  85                 }
  86         }
  87
  88         /**
  89          * Report aggregation
  90          */
  91         public static class Reports {
  92                 public boolean healthy;
  93                 public ArrayList<Report> details = new ArrayList<>();
  94
  95                 @Override
  96                 public String toString() {
  97                         StringBuilder builder = new StringBuilder();
  98                         builder.append("Reports [healthy=");
  99                         builder.append(healthy);
 100                         builder.append(", details=");
 101                         builder.append(details);
 102                         builder.append("]");
 103                         return builder.toString();
 104                 }
 105         }
 106
 107         /**
 108          * perform a healthcheck
 109          * @return a report
 110          */
 111         public Reports healthCheck();
 112
 113         /**
 114          * Healthcheck Monitor
 115          */
 116         public static final HealthCheck monitor = new HealthCheckMonitor();
 117 }
 118
 119 /**
 120  * Healthcheck Monitor
 121  */
 122 class HealthCheckMonitor implements HealthCheck {
 123
 124         /**
 125          * Logger
 126          */
 127         private static Logger logger = LoggerFactory.getLogger(HealthCheckMonitor.class);
 128
 129         /**
 130          * attached http servers
 131          */
 132         protected volatile ArrayList<HttpServletServer> servers = new ArrayList<>();
 133
 134         /**
 135          * attached http clients
 136          */
 137         protected volatile ArrayList<HttpClient> clients = new ArrayList<>();
 138
 139         /**
 140          * healthcheck configuration
 141          */
 142         protected volatile Properties healthCheckProperties = null;
 143
 144         /**
 145          * {@inheritDoc}
 146          */
 147         public Reports healthCheck() {
 148                 Reports reports = new Reports();
 149                 reports.healthy = PolicyEngine.manager.isAlive();
 150
 151                 HealthCheck.Report engineReport = new Report();
 152                 engineReport.healthy = PolicyEngine.manager.isAlive();
 153                 engineReport.name = "PDP-D";
 154                 engineReport.url = "self";
 155                 engineReport.code = (PolicyEngine.manager.isAlive()) ? 200 : 500;
 156                 engineReport.message = (PolicyEngine.manager.isAlive()) ? "alive" : "not alive";
 157                 reports.details.add(engineReport);
 158
 159                 for (HttpClient client : clients) {
 160                         HealthCheck.Report report = new Report();
 161                         report.name = client.getName();
 162                         report.url = client.getBaseUrl();
 163                         report.healthy = true;
 164                         try {
 165                                 Response response = client.get();
 166                                 report.code = response.getStatus();
 167                                 if (report.code != 200) {
 168                                         report.healthy = false;
 169                                         reports.healthy = false;
 170                                 }
 171
 172                                 try {
 173                                         report.message = HttpClient.getBody(response, String.class);
 174                                 } catch (Exception e) {
 175                                         logger.warn("{}: cannot get body from http-client {}", this, client, e);
 176                                 }
 177                         } catch (Exception e) {
 178                                 report.healthy = false;
 179                                 reports.healthy = false;
 180                         }
 181                         reports.details.add(report);
 182                 }
 183                 return reports;
 184         }
 185
 186         /**
 187          * {@inheritDoc}
 188          */
 189         @Override
 190         public boolean start() throws IllegalStateException {
 191
 192                 try {
 193                         this.healthCheckProperties = SystemPersistence.manager.getProperties(HealthCheckFeature.CONFIGURATION_PROPERTIES_NAME);
 194                         this.servers = HttpServletServer.factory.build(healthCheckProperties);
 195                         this.clients = HttpClient.factory.build(healthCheckProperties);
 196
 197                         for (HttpServletServer server : servers) {
 198                                 try {
 199                                         server.start();
 200                                 } catch (Exception e) {
 201                                         logger.warn("{}: cannot start http-server {}", this, server, e);
 202                                 }
 203                         }
 204                 } catch (Exception e) {
 205                         return false;
 206                 }
 207
 208                 return true;
 209         }
 210
 211         /**
 212          * {@inheritDoc}
 213          */
 214         @Override
 215         public boolean stop() throws IllegalStateException {
 216
 217                 for (HttpServletServer server : servers) {
 218                         try {
 219                                 server.stop();
 220                         } catch (Exception e) {
 221                                 logger.warn("{}: cannot stop http-server {}", this, server, e);
 222                         }
 223                 }
 224
 225                 for (HttpClient client : clients) {
 226                         try {
 227                                 client.stop();
 228                         } catch (Exception e) {
 229                                 logger.warn("{}: cannot stop http-client {}", this, client, e);
 230                         }
 231                 }
 232
 233                 return true;
 234         }
 235
 236         /**
 237          * {@inheritDoc}
 238          */
 239         @Override
 240         public void shutdown() throws IllegalStateException {
 241                 this.stop();
 242         }
 243
 244         /**
 245          * {@inheritDoc}
 246          */
 247         @Override
 248         public synchronized boolean isAlive() {
 249                 return this.healthCheckProperties != null;
 250         }
 251
 252         /**
 253          * @return list of attached Http Servers
 254          */
 255         public ArrayList<HttpServletServer> getServers() {
 256                 return this.servers;
 257         }
 258
 259         /**
 260          * @return list of attached Http Clients
 261          */
 262         public ArrayList<HttpClient> getClients() {
 263                 return this.clients;
 264         }
 265
 266         @Override
 267         public String toString() {
 268                 StringBuilder builder = new StringBuilder();
 269                 builder.append("HealthCheckMonitor [servers=");
 270                 builder.append(servers);
 271                 builder.append(", clients=");
 272                 builder.append(clients);
 273                 builder.append("]");
 274                 return builder.toString();
 275         }
 276
 277 }