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

   1 /**
   2  * ============LICENSE_START====================================================
   3  * org.onap.aaf
   4  * ===========================================================================
   5  * Copyright (c) 2018 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
  22 package org.onap.aaf.cadi.locator;
  23
  24 import java.io.IOException;
  25 import java.net.InetAddress;
  26 import java.net.URI;
  27 import java.net.URISyntaxException;
  28
  29 import org.onap.aaf.cadi.Access;
  30 import org.onap.aaf.cadi.Locator;
  31 import org.onap.aaf.cadi.LocatorException;
  32 import org.onap.aaf.cadi.Access.Level;
  33
  34 public class DNSLocator implements Locator<URI> {
  35         private static enum Status {UNTRIED, OK, INVALID, SLOW};
  36         private static final int CHECK_TIME = 3000;
  37
  38         private String host, protocol;
  39         private Access access;
  40         private Host[] hosts;
  41         private int startPort, endPort;
  42         private String suffix;
  43
  44         public DNSLocator(Access access, String protocol, String host, String range) {
  45                 this.host = host;
  46                 this.protocol = protocol;
  47                 this.access = access;
  48                 int dash = range.indexOf('-');
  49                 if(dash<0) {
  50                         startPort = endPort = Integer.parseInt(range);
  51                 } else {
  52                         startPort = Integer.parseInt(range.substring(0,dash));
  53                         endPort = Integer.parseInt(range.substring(dash + 1));
  54                 }
  55                 refresh();
  56         }
  57
  58         public DNSLocator(Access access, String aaf_locate) throws LocatorException {
  59                 this.access = access;
  60                 if(aaf_locate==null) {
  61                         throw new LocatorException("Null passed into DNSLocator constructor");
  62                 }
  63                 int start, port;
  64                 if(aaf_locate.startsWith("https:")) {
  65                         protocol = "https:";
  66                         start = 9; // https://
  67                         port = 443;
  68                 } else if(aaf_locate.startsWith("http:")) {
  69                         protocol = "http:";
  70                         start = 8; // http://
  71                         port = 80;
  72                 } else {
  73                         throw new LocatorException("DNSLocator accepts only https or http protocols.  (requested URL " + aaf_locate + ')');
  74                 }
  75
  76                 int colon = aaf_locate.indexOf(':',start);
  77                 int slash;
  78                 if(colon>0) {
  79                         start = colon+1;
  80                         int left = aaf_locate.indexOf('[',start);
  81                         if(left>0) {
  82                                 int right = aaf_locate.indexOf(']',left+1);
  83                                 if(right>0) {
  84                                         int dash = aaf_locate.indexOf('-',left+1);
  85                                         if(dash<0) {
  86                                                 startPort = endPort = Integer.parseInt(aaf_locate.substring(left+1,right));
  87                                         } else {
  88                                                 startPort = Integer.parseInt(aaf_locate.substring(left+1,dash));
  89                                                 endPort = Integer.parseInt(aaf_locate.substring(dash + 1,right));
  90                                         }
  91                                 }
  92
  93                         } else {
  94                                 slash = aaf_locate.indexOf('/',colon+1);
  95                                 if(slash<0) {
  96                                         startPort = endPort = Integer.parseInt(aaf_locate.substring(start));
  97                                 } else {
  98                                         startPort = endPort = Integer.parseInt(aaf_locate.substring(start,slash));
  99                                 }
 100                         }
 101                 } else {
 102                         startPort = endPort = port;
 103                 }
 104         }
 105
 106         @Override
 107         public URI get(Item item) throws LocatorException {
 108                 return hosts[((DLItem)item).cnt].uri;
 109         }
 110
 111         @Override
 112         public boolean hasItems() {
 113                 for(Host h : hosts) {
 114                         if(h.status==Status.OK) {
 115                                 return true;
 116                         }
 117                 }
 118                 return false;
 119         }
 120
 121         @Override
 122         public void invalidate(Item item) {
 123                 DLItem di = (DLItem)item;
 124                 hosts[di.cnt].status = Status.INVALID;
 125         }
 126
 127         @Override
 128         public Item best() throws LocatorException {
 129                 // not a good "best"
 130                 for(int i=0;i<hosts.length;++i) {
 131                         switch(hosts[i].status) {
 132                                 case OK:
 133                                         return new DLItem(i);
 134                                 case INVALID:
 135                                         break;
 136                                 case SLOW:
 137                                         break;
 138                                 case UNTRIED:
 139                                         try {
 140                                                 if(hosts[i].ia.isReachable(CHECK_TIME)) {
 141                                                         hosts[i].status = Status.OK;
 142                                                         return new DLItem(i);
 143                                                 }
 144                                         } catch (IOException e) {
 145                                                 throw new LocatorException(e);
 146                                         }
 147                                         break;
 148                                 default:
 149                                         break;
 150                         }
 151                 }
 152                 throw new LocatorException("No Available URIs for " + host);
 153         }
 154
 155         @Override
 156         public Item first() throws LocatorException {
 157                 return new DLItem(0);
 158         }
 159
 160         @Override
 161         public Item next(Item item) throws LocatorException {
 162                 DLItem di = (DLItem)item;
 163                 if(++di.cnt<hosts.length) {
 164                         return di;
 165                 } else {
 166                         return null;
 167                 }
 168         }
 169
 170         @Override
 171         public boolean refresh() {
 172                 try {
 173                         InetAddress[] ias = InetAddress.getAllByName(host);
 174                         Host[] temp = new Host[ias.length * (1 + endPort - startPort)];
 175                         int cnt = -1;
 176                         for(int j=startPort; j<=endPort; ++j) {
 177                                 for(int i=0;i<ias.length;++i) {
 178                                         temp[++cnt] = new Host(ias[i], j, suffix);
 179                                 }
 180                         }
 181                         hosts = temp;
 182                         return true;
 183                 } catch (Exception e) {
 184                         access.log(Level.ERROR, e);
 185                 }
 186                 return false;
 187         }
 188
 189         private class Host {
 190                 private URI uri;
 191                 private InetAddress ia;
 192                 private Status status;
 193
 194                 public Host(InetAddress inetAddress, int port, String suffix) throws URISyntaxException {
 195                         ia = inetAddress;
 196                         uri = new URI(protocol,null,inetAddress.getHostAddress(),port,suffix,null,null);
 197                         status = Status.UNTRIED;
 198                 }
 199         }
 200
 201         private class DLItem implements Item {
 202                 public DLItem(int i) {
 203                         cnt = i;
 204                 }
 205
 206                 private int cnt;
 207         }
 208
 209         public void destroy() {}
 210 }