client/src/main/java/org/onap/aaf/cadi/locator/DNSLocator.java

   1 /*******************************************************************************\r
   2  * ============LICENSE_START====================================================\r
   3  * * org.onap.aaf\r
   4  * * ===========================================================================\r
   5  * * Copyright © 2017 AT&T Intellectual Property. All rights reserved.\r
   6  * * ===========================================================================\r
   7  * * Licensed under the Apache License, Version 2.0 (the "License");\r
   8  * * you may not use this file except in compliance with the License.\r
   9  * * You may obtain a copy of the License at\r
  10  * * \r
  11  *  *      http://www.apache.org/licenses/LICENSE-2.0\r
  12  * * \r
  13  *  * Unless required by applicable law or agreed to in writing, software\r
  14  * * distributed under the License is distributed on an "AS IS" BASIS,\r
  15  * * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\r
  16  * * See the License for the specific language governing permissions and\r
  17  * * limitations under the License.\r
  18  * * ============LICENSE_END====================================================\r
  19  * *\r
  20  * * ECOMP is a trademark and service mark of AT&T Intellectual Property.\r
  21  * *\r
  22  ******************************************************************************/\r
  23 package org.onap.aaf.cadi.locator;\r
  24 \r
  25 import java.io.IOException;\r
  26 import java.net.InetAddress;\r
  27 import java.net.URI;\r
  28 import java.net.URISyntaxException;\r
  29 \r
  30 import org.onap.aaf.cadi.Access;\r
  31 import org.onap.aaf.cadi.Locator;\r
  32 import org.onap.aaf.cadi.LocatorException;\r
  33 import org.onap.aaf.cadi.Access.Level;\r
  34 \r
  35 public class DNSLocator implements Locator<URI> {\r
  36         private static enum Status {UNTRIED, OK, INVALID, SLOW};\r
  37         private static final int CHECK_TIME = 3000;\r
  38         \r
  39         private String host, protocol;\r
  40         private Access access;\r
  41         private Host[] hosts;\r
  42         private int startPort, endPort;\r
  43         private String suffix;\r
  44         \r
  45         public DNSLocator(Access access, String protocol, String host, String range) {\r
  46                 this.host = host;\r
  47                 this.protocol = protocol;\r
  48                 this.access = access;\r
  49                 int dash = range.indexOf('-');\r
  50                 if(dash<0) {\r
  51                         startPort = endPort = Integer.parseInt(range);\r
  52                 } else {\r
  53                         startPort = Integer.parseInt(range.substring(0,dash));\r
  54                         endPort = Integer.parseInt(range.substring(dash + 1));\r
  55                 }\r
  56                 refresh();\r
  57         }\r
  58 \r
  59         @Override\r
  60         public URI get(Item item) throws LocatorException {\r
  61                 return hosts[((DLItem)item).cnt].uri;\r
  62         }\r
  63 \r
  64         @Override\r
  65         public boolean hasItems() {\r
  66                 for(Host h : hosts) {\r
  67                         if(h.status==Status.OK) {\r
  68                                 return true;\r
  69                         }\r
  70                 }\r
  71                 return false;\r
  72         }\r
  73 \r
  74         @Override\r
  75         public void invalidate(Item item) {\r
  76                 DLItem di = (DLItem)item;\r
  77                 hosts[di.cnt].status = Status.INVALID;\r
  78         }\r
  79 \r
  80         @Override\r
  81         public Item best() throws LocatorException {\r
  82                 // not a good "best"\r
  83                 for(int i=0;i<hosts.length;++i) {\r
  84                         switch(hosts[i].status) {\r
  85                                 case OK:\r
  86                                         return new DLItem(i);\r
  87                                 case INVALID:\r
  88                                         break;\r
  89                                 case SLOW:\r
  90                                         break;\r
  91                                 case UNTRIED:\r
  92                                         try {\r
  93                                                 if(hosts[i].ia.isReachable(CHECK_TIME)) {\r
  94                                                         hosts[i].status = Status.OK;\r
  95                                                         return new DLItem(i);\r
  96                                                 }\r
  97                                         } catch (IOException e) {\r
  98                                                 throw new LocatorException(e);\r
  99                                         }\r
 100                                         break;\r
 101                                 default:\r
 102                                         break;\r
 103                         }\r
 104                 }\r
 105                 throw new LocatorException("No Available URIs for " + host);\r
 106         }\r
 107 \r
 108         @Override\r
 109         public Item first() throws LocatorException {\r
 110                 return new DLItem(0);\r
 111         }\r
 112 \r
 113         @Override\r
 114         public Item next(Item item) throws LocatorException {\r
 115                 DLItem di = (DLItem)item;\r
 116                 if(++di.cnt<hosts.length) {\r
 117                         return di;\r
 118                 } else {\r
 119                         return null;\r
 120                 }\r
 121         }\r
 122 \r
 123         @Override\r
 124         public boolean refresh() {\r
 125                 try {\r
 126                         InetAddress[] ias = InetAddress.getAllByName(host);\r
 127                         Host[] temp = new Host[ias.length * (1 + endPort - startPort)];\r
 128                         int cnt = -1;\r
 129                         for(int j=startPort; j<=endPort; ++j) {\r
 130                                 for(int i=0;i<ias.length;++i) {\r
 131                                         temp[++cnt] = new Host(ias[i], j, suffix);\r
 132                                 }\r
 133                         }\r
 134                         hosts = temp;\r
 135                         return true;\r
 136                 } catch (Exception e) {\r
 137                         access.log(Level.ERROR, e);\r
 138                 }\r
 139                 return false;\r
 140         }\r
 141 \r
 142         private class Host {\r
 143                 private URI uri;\r
 144                 private InetAddress ia;\r
 145                 private Status status;\r
 146                 \r
 147                 public Host(InetAddress inetAddress, int port, String suffix) throws URISyntaxException {\r
 148                         ia = inetAddress;\r
 149                         uri = new URI(protocol,null,inetAddress.getHostAddress(),port,suffix,null,null);\r
 150                         status = Status.UNTRIED;\r
 151                 }\r
 152         }\r
 153         \r
 154         private class DLItem implements Item {\r
 155                 public DLItem(int i) {\r
 156                         cnt = i;\r
 157                 }\r
 158 \r
 159                 private int cnt;\r
 160         }\r
 161         \r
 162         public void destroy() {}\r
 163 }\r