1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
|
/* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-
* vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
*
* Copyright (C) 2008-2009 Sun Microsystems, Inc.
* Copyright (C) 2009-2010 Jay Pipes <jaypipes@gmail.com>
*
* Authors:
*
* Jay Pipes <jaypipes@gmail.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file Server-side utility which is responsible for managing the
* communication between the kernel and the replication plugins:
*
* - TransactionReplicator
* - TransactionApplier
* - Publisher
* - Subscriber
*
* ReplicationServices is a bridge between replication modules and the kernel,
* and its primary function is to */
#include <config.h>
#include <drizzled/replication_services.h>
#include <drizzled/plugin/transaction_replicator.h>
#include <drizzled/plugin/transaction_applier.h>
#include <drizzled/message/transaction.pb.h>
#include <drizzled/gettext.h>
#include <drizzled/session.h>
#include <drizzled/error.h>
#include <drizzled/errmsg_print.h>
#include <string>
#include <vector>
#include <algorithm>
using namespace std;
namespace drizzled {
typedef std::vector<plugin::TransactionReplicator*> Replicators;
typedef std::vector<std::pair<std::string, plugin::TransactionApplier*> > Appliers;
/**
* Atomic boolean set to true if any *active* replicators
* or appliers are actually registered.
*/
static bool is_active= false;
/**
* The timestamp of the last time a Transaction message was successfully
* applied (sent to an Applier)
*/
static atomic<uint64_t> last_applied_timestamp;
/** Our collection of registered replicator plugins */
static Replicators replicators;
/** Our collection of registered applier plugins and their requested replicator plugin names */
static Appliers appliers;
/** Our replication streams */
static ReplicationServices::ReplicationStreams replication_streams;
/**
* Strips underscores and lowercases supplied replicator name
* or requested name, and appends the suffix "replicator" if missing...
*/
static void normalizeReplicatorName(string &name)
{
boost::to_lower(name);
if (name.find("replicator") == string::npos)
name.append("replicator");
{
size_t found_underscore= name.find('_');
while (found_underscore != string::npos)
{
name.erase(found_underscore, 1);
found_underscore= name.find('_');
}
}
}
bool ReplicationServices::evaluateRegisteredPlugins()
{
/*
* We loop through appliers that have registered with us
* and attempts to pair the applier with its requested
* replicator. If an applier has requested a replicator
* that has either not been built or has not registered
* with the replication services, we print an error and
* return false
*/
if (appliers.empty())
return true;
if (replicators.empty() && not appliers.empty())
{
errmsg_printf(error::ERROR,
N_("You registered a TransactionApplier plugin but no "
"TransactionReplicator plugins were registered.\n"));
return false;
}
BOOST_FOREACH(Appliers::reference appl_iter, appliers)
{
plugin::TransactionApplier *applier= appl_iter.second;
string requested_replicator_name= appl_iter.first;
normalizeReplicatorName(requested_replicator_name);
bool found= false;
Replicators::iterator repl_iter;
for (repl_iter= replicators.begin(); repl_iter != replicators.end(); ++repl_iter)
{
string replicator_name= (*repl_iter)->getName();
normalizeReplicatorName(replicator_name);
if (requested_replicator_name.compare(replicator_name) == 0)
{
found= true;
break;
}
}
if (not found)
{
errmsg_printf(error::ERROR,
N_("You registered a TransactionApplier plugin but no "
"TransactionReplicator plugins were registered that match the "
"requested replicator name of '%s'.\n"
"We have deactivated the TransactionApplier '%s'.\n"),
requested_replicator_name.c_str(),
applier->getName().c_str());
applier->deactivate();
return false;
}
else
{
replication_streams.push_back(make_pair(*repl_iter, applier));
}
}
is_active= true;
return true;
}
void ReplicationServices::attachReplicator(plugin::TransactionReplicator *in_replicator)
{
replicators.push_back(in_replicator);
}
void ReplicationServices::detachReplicator(plugin::TransactionReplicator *in_replicator)
{
replicators.erase(std::find(replicators.begin(), replicators.end(), in_replicator));
}
void ReplicationServices::attachApplier(plugin::TransactionApplier *in_applier, const string &requested_replicator_name)
{
appliers.push_back(make_pair(requested_replicator_name, in_applier));
}
void ReplicationServices::detachApplier(plugin::TransactionApplier *)
{
}
bool ReplicationServices::isActive()
{
return is_active;
}
plugin::ReplicationReturnCode ReplicationServices::pushTransactionMessage(Session &in_session,
message::Transaction &to_push)
{
plugin::ReplicationReturnCode result= plugin::SUCCESS;
BOOST_FOREACH(ReplicationStreams::reference iter, replication_streams)
{
plugin::TransactionReplicator *cur_repl= iter.first;
plugin::TransactionApplier *cur_appl= iter.second;
result= cur_repl->replicate(cur_appl, in_session, to_push);
if (result == plugin::SUCCESS)
{
/*
* We update the timestamp for the last applied Transaction so that
* publisher plugins can ask the replication services when the
* last known applied Transaction was using the getLastAppliedTimestamp()
* method.
*/
last_applied_timestamp.fetch_and_store(to_push.transaction_context().end_timestamp());
}
else
return result;
}
return result;
}
ReplicationServices::ReplicationStreams &ReplicationServices::getReplicationStreams()
{
return replication_streams;
}
} /* namespace drizzled */
|