|
132
|
1 /*******************************************************************************
|
|
|
2
|
|
|
3 copyright: Copyright (c) 2004 Kris Bell. All rights reserved
|
|
|
4
|
|
|
5 license: BSD style: $(LICENSE)
|
|
|
6
|
|
|
7 version: July 2004: Initial release
|
|
|
8
|
|
|
9 author: Kris
|
|
|
10
|
|
|
11 *******************************************************************************/
|
|
|
12
|
|
|
13 module tango.net.cluster.tina.ClusterServer;
|
|
|
14
|
|
|
15 private import tango.core.Thread;
|
|
|
16
|
|
|
17 private import tango.util.ArgParser;
|
|
|
18
|
|
|
19 private import tango.net.Socket,
|
|
|
20 tango.net.InternetAddress;
|
|
|
21
|
|
|
22 private import tango.net.cluster.tina.Cluster,
|
|
|
23 tango.net.cluster.tina.RollCall;
|
|
|
24
|
|
|
25 private import tango.net.cluster.NetworkRegistry;
|
|
|
26
|
|
|
27 private import tango.net.cluster.tina.util.ServerThread;
|
|
|
28
|
|
|
29 package import tango.net.cluster.tina.util.AbstractServer;
|
|
|
30
|
|
|
31 /******************************************************************************
|
|
|
32
|
|
|
33 Extends the AbstractServer to glue cluster support together.
|
|
|
34
|
|
|
35 ******************************************************************************/
|
|
|
36
|
|
|
37 abstract class ClusterServer : AbstractServer
|
|
|
38 {
|
|
|
39 package char[] name;
|
|
|
40 package Cluster cluster;
|
|
|
41 package IChannel channel;
|
|
|
42 package RollCall rollcall;
|
|
|
43
|
|
|
44 /**********************************************************************
|
|
|
45
|
|
|
46 Concrete server must expose a service handler
|
|
|
47
|
|
|
48 **********************************************************************/
|
|
|
49
|
|
|
50 abstract void service (IConduit conduit);
|
|
|
51
|
|
|
52 /**********************************************************************
|
|
|
53
|
|
|
54 Construct this server with the requisite attributes. The
|
|
|
55 'bind' address is the local address we'll be listening on,
|
|
|
56 'threads' represents the number of socket-accept threads,
|
|
|
57 and backlog is the number of "simultaneous" connection
|
|
|
58 requests that a socket layer will buffer on our behalf.
|
|
|
59
|
|
|
60 We also set up a listener for client discovery-requests,
|
|
|
61 and lastly, we tell active clients that we're available
|
|
|
62 for work. Clients should be listening on the appropriate
|
|
|
63 channel for an instance of the RollCall payload.
|
|
|
64
|
|
|
65 **********************************************************************/
|
|
|
66
|
|
|
67 this (char[] name, InternetAddress bind, Logger logger)
|
|
|
68 {
|
|
|
69 this.name = name;
|
|
|
70
|
|
|
71 super (bind, 1, 50, logger);
|
|
|
72
|
|
|
73 // hook into the cluster as a server
|
|
|
74 cluster = new Cluster (logger);
|
|
|
75 }
|
|
|
76
|
|
|
77 /**********************************************************************
|
|
|
78
|
|
|
79 **********************************************************************/
|
|
|
80
|
|
|
81 void enroll (IMessage task)
|
|
|
82 {
|
|
|
83 NetworkRegistry.shared.enroll (task);
|
|
|
84 }
|
|
|
85
|
|
|
86 /**********************************************************************
|
|
|
87
|
|
|
88 Start the server
|
|
|
89
|
|
|
90 Note that we hijack the calling thread, and use it to
|
|
|
91 generate a hearbeat. The hearbeat has two functions: it
|
|
|
92 tells all clients when this server starts, and it tells
|
|
|
93 them we're still alive. The latter is important if, for
|
|
|
94 example, a client request to this server had timed-out
|
|
|
95 due to the server being too busy. In such a case, the
|
|
|
96 client will mark the server as being unavailable, and
|
|
|
97 the heartbeat will presumably revert that.
|
|
|
98
|
|
|
99 It would also be useful to monitor the GC from here.
|
|
|
100
|
|
|
101 **********************************************************************/
|
|
|
102
|
|
|
103 void start (RollCall id, bool reuse=false)
|
|
|
104 {
|
|
|
105 super.start (reuse);
|
|
|
106
|
|
|
107 // configure an identity for ourselves
|
|
|
108 id.addr = Socket.hostName ~ ':' ~ localAddress.toPortString;
|
|
|
109 this.rollcall = id;
|
|
|
110
|
|
|
111 // clients are listening on this channel ...
|
|
|
112 channel = cluster.createChannel ("cluster.server.advertise");
|
|
|
113
|
|
|
114 // ... and listen for subsequent server.advertise requests
|
|
|
115 channel.createBulletinConsumer (¬ify);
|
|
|
116
|
|
|
117 while (true)
|
|
|
118 {
|
|
|
119 getLogger.trace ("heartbeat");
|
|
|
120 channel.broadcast (rollcall);
|
|
|
121 Thread.sleep (30.0);
|
|
|
122 }
|
|
|
123 }
|
|
|
124
|
|
|
125 /**********************************************************************
|
|
|
126
|
|
|
127 Return a text string identifying this server
|
|
|
128
|
|
|
129 **********************************************************************/
|
|
|
130
|
|
|
131 char[] getProtocol ()
|
|
|
132 {
|
|
|
133 return name;
|
|
|
134 }
|
|
|
135
|
|
|
136 /**********************************************************************
|
|
|
137
|
|
|
138 Return a text string identifying this server
|
|
|
139
|
|
|
140 **********************************************************************/
|
|
|
141
|
|
|
142 override char[] toString ()
|
|
|
143 {
|
|
|
144 return "cluster::" ~ name;
|
|
|
145 }
|
|
|
146
|
|
|
147 /**********************************************************************
|
|
|
148
|
|
|
149 Create a ServerSocket instance.
|
|
|
150
|
|
|
151 **********************************************************************/
|
|
|
152
|
|
|
153 override ServerSocket createSocket (InternetAddress bind, int backlog, bool reuse=false)
|
|
|
154 {
|
|
|
155 return new ServerSocket (bind, backlog, reuse);
|
|
|
156 }
|
|
|
157
|
|
|
158 /**********************************************************************
|
|
|
159
|
|
|
160 Create a ServerThread instance. This can be overridden to
|
|
|
161 create other thread-types, perhaps with additional thread-
|
|
|
162 level data attached.
|
|
|
163
|
|
|
164 **********************************************************************/
|
|
|
165
|
|
|
166 override void createThread (ServerSocket socket)
|
|
|
167 {
|
|
|
168 new ServerThread (this, socket);
|
|
|
169 }
|
|
|
170
|
|
|
171 /**********************************************************************
|
|
|
172
|
|
|
173 Interface method that's invoked when a client is making
|
|
|
174 discovery requests. We just send back our identity in a
|
|
|
175 reply
|
|
|
176
|
|
|
177 **********************************************************************/
|
|
|
178
|
|
|
179 private void notify (IEvent event)
|
|
|
180 {
|
|
|
181 scope input = new RollCall;
|
|
|
182 event.get (input);
|
|
|
183
|
|
|
184 // if this is a request, reply with our identity
|
|
|
185 if (input.type is input.Request)
|
|
|
186 channel.broadcast (rollcall);
|
|
|
187 }
|
|
|
188 }
|
|
|
189
|
