1 /*
2 * #%L
3 * ReplicaSetConnection.java - mongodb-async-driver - Allanbank Consulting, Inc.
4 * %%
5 * Copyright (C) 2011 - 2014 Allanbank Consulting, Inc.
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 * #L%
19 */
20
21 package com.allanbank.mongodb.client.connection.rs;
22
23 import java.io.IOException;
24 import java.util.List;
25
26 import com.allanbank.mongodb.MongoClientConfiguration;
27 import com.allanbank.mongodb.MongoDbException;
28 import com.allanbank.mongodb.client.Message;
29 import com.allanbank.mongodb.client.connection.Connection;
30 import com.allanbank.mongodb.client.connection.proxy.AbstractProxyMultipleConnection;
31 import com.allanbank.mongodb.client.connection.proxy.ConnectionInfo;
32 import com.allanbank.mongodb.client.connection.proxy.ProxiedConnectionFactory;
33 import com.allanbank.mongodb.client.state.Cluster;
34 import com.allanbank.mongodb.client.state.Server;
35 import com.allanbank.mongodb.util.log.Log;
36 import com.allanbank.mongodb.util.log.LogFactory;
37
38 /**
39 * Provides a {@link Connection} implementation for connecting to a replica-set
40 * environment.
41 *
42 * @api.no This class is <b>NOT</b> part of the drivers API. This class may be
43 * mutated in incompatible ways between any two releases of the driver.
44 * @copyright 2011-2013, Allanbank Consulting, Inc., All Rights Reserved
45 */
46 public class ReplicaSetConnection extends
47 AbstractProxyMultipleConnection<Server> {
48
49 /** The logger for the {@link ReplicaSetConnection}. */
50 private static final Log LOG = LogFactory
51 .getLog(ReplicaSetConnection.class);
52
53 /** The strategy for reconnecting/finding the primary. */
54 private volatile ReplicaSetReconnectStrategy myReconnectStrategy;
55
56 /**
57 * Creates a new {@link ReplicaSetConnection}.
58 *
59 * @param proxiedConnection
60 * The connection being proxied.
61 * @param server
62 * The primary server this connection is connected to.
63 * @param cluster
64 * The state of the cluster for finding secondary connections.
65 * @param factory
66 * The connection factory for opening secondary connections.
67 * @param config
68 * The MongoDB client configuration.
69 * @param strategy
70 * The strategy for reconnecting/finding the primary.
71 */
72 public ReplicaSetConnection(final Connection proxiedConnection,
73 final Server server, final Cluster cluster,
74 final ProxiedConnectionFactory factory,
75 final MongoClientConfiguration config,
76 final ReplicaSetReconnectStrategy strategy) {
77 super(proxiedConnection, server, cluster, factory, config);
78
79 myReconnectStrategy = strategy;
80 }
81
82 /**
83 * {@inheritDoc}
84 * <p>
85 * Overridden to return the canonical name of the primary.
86 * </p>
87 */
88 @Override
89 public String getServerName() {
90 if (myMainKey != null) {
91 return myMainKey.getCanonicalName();
92 }
93 return "UNKNOWN";
94 }
95
96 /**
97 * {@inheritDoc}
98 * <p>
99 * Overridden to create a connection to the server.
100 * </p>
101 */
102 @Override
103 protected Connection connect(final Server server) {
104 Connection conn = null;
105 try {
106 conn = myFactory.connect(server, myConfig);
107
108 conn = cacheConnection(server, conn);
109 }
110 catch (final IOException e) {
111 LOG.info("Could not connect to the server '"
112 + server.getCanonicalName() + "': " + e.getMessage());
113 }
114 return conn;
115 }
116
117 /**
118 * Locates the set of servers that can be used to send the specified
119 * messages. This method will attempt to connect to the primary server if
120 * there is not a current connection to the primary.
121 *
122 * @param message1
123 * The first message to send.
124 * @param message2
125 * The second message to send. May be <code>null</code>.
126 * @return The servers that can be used.
127 * @throws MongoDbException
128 * On a failure to locate a server that all messages can be sent
129 * to.
130 */
131 @Override
132 protected List<Server> findPotentialKeys(final Message message1,
133 final Message message2) throws MongoDbException {
134 List<Server> servers = myCluster.findServers(message1, message2);
135
136 if (servers.isEmpty()) {
137 // If we get here and a reconnect is in progress then
138 // block for the reconnect. The primary will have been marked a
139 // secondary... Once the reconnect is complete, try again.
140 if (myMainKey == null) {
141 // Wait for a reconnect.
142 final ConnectionInfo<Server> newConnInfo = reconnectMain();
143 if (newConnInfo != null) {
144 updateMain(newConnInfo);
145 servers = myCluster.findServers(message1, message2);
146 }
147 }
148
149 if (servers.isEmpty()) {
150 throw createReconnectFailure(message1, message2);
151 }
152 }
153
154 return servers;
155 }
156
157 /**
158 * {@inheritDoc}
159 * <p>
160 * Overridden to return the string {@code ReplicaSet}.
161 * </p>
162 */
163 @Override
164 protected String getConnectionType() {
165 return "ReplicaSet";
166 }
167
168 /**
169 * {@inheritDoc}
170 * <p>
171 * Overridden creates a connection back to the primary server.
172 * </p>
173 */
174 @Override
175 protected ConnectionInfo<Server> reconnectMain() {
176 return myReconnectStrategy.reconnectPrimary();
177 }
178
179 }