/* * 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. */ package org.bitsofinfo.hazelcast.spi.docker.swarm.dnsrr.discovery; import com.hazelcast.logging.ILogger; import com.hazelcast.nio.Address; import com.hazelcast.spi.discovery.AbstractDiscoveryStrategy; import com.hazelcast.spi.discovery.DiscoveryNode; import com.hazelcast.spi.discovery.SimpleDiscoveryNode; import java.net.InetAddress; import java.net.UnknownHostException; import java.util.Arrays; import java.util.HashSet; import java.util.LinkedList; import java.util.Map; import java.util.Set; /** * Hazelcast discovery strategy to be used with docker endpoint_mode: dnsrr * This expects a CSV of peer services and resolves each one to component IP * addresses within the docker network to connect to each individually. * * @author Cardds */ public class DockerDNSRRDiscoveryStrategy extends AbstractDiscoveryStrategy { private ILogger logger; public DockerDNSRRDiscoveryStrategy( ILogger logger, //The Comparable raw type is defined by AbstractDiscoveryStrategy as //the value for the properties element; passing through here @SuppressWarnings("rawtypes") Map<String, Comparable> properties ) { super(logger, properties); this.logger = logger; } @Override public Iterable<DiscoveryNode> discoverNodes() { LinkedList<DiscoveryNode> discoveryNodes = new LinkedList<>(); //Pull properties String servicesCsv = getOrDefault( DockerDNSRRDiscoveryConfiguration.SERVICESCSV, "" ); //If there are no services configured, no point in doing anything. if ( servicesCsv == null || servicesCsv.trim().isEmpty() ) { return discoveryNodes; } Set<InetAddress> serviceNameResolutions = new HashSet<>(); String[] serviceHostnameAndPort; Integer port = 5701; //Loop for every service defined in the CSV for (String service : servicesCsv.split(",")) { if (!service.trim().isEmpty()) { //CSV should be composed of hostname:port serviceHostnameAndPort = service.split(":"); //Validate hostname exists if ( serviceHostnameAndPort[0] == null || serviceHostnameAndPort[0].trim().isEmpty() ) { logger.info( "Unable to resolve service hostname " + serviceHostnameAndPort[0] + " Skipping service entry." ); continue; } //Validate port exists; assume default port if it doesn't if ( serviceHostnameAndPort.length <= 1 || serviceHostnameAndPort[1] == null || serviceHostnameAndPort[1].trim().isEmpty() ) { port = 5701; } else { try { port = Integer.valueOf( serviceHostnameAndPort[1] ); } catch (NumberFormatException nfe) { logger.info( "Unable to parse port " + serviceHostnameAndPort[1] + " Skipping service entry." ); continue; } } //Resolve service hostname to a set of IP addresses, if any serviceNameResolutions = resolveDomainNames( serviceHostnameAndPort[0] ); //Add all IP addresses for service hostname with the given port. for (InetAddress resolution : serviceNameResolutions) { discoveryNodes.add( new SimpleDiscoveryNode( new Address( resolution, port ) ) ); } } } return discoveryNodes; } private Set<InetAddress> resolveDomainNames(String domainName) { Set<InetAddress> addresses = new HashSet<>(); try { InetAddress[] inetAddresses; inetAddresses = InetAddress.getAllByName(domainName); addresses.addAll( Arrays.asList(inetAddresses) ); logger.info( "Resolved domain name '" + domainName + "' to address(es): " + addresses ); } catch (UnknownHostException e) { logger.severe( "Unable to resolve domain name " + domainName ); } return addresses; } }