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
|
/* Helloworld cluster -- A ping/pong cluster API example.
*
* -----------------------------------------------------------------------------
*
* Copyright (c) 2018, Salvatore Sanfilippo <antirez at gmail dot com>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of Redis nor the names of its contributors may be used
* to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include "../redismodule.h"
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>
#define MSGTYPE_PING 1
#define MSGTYPE_PONG 2
/* HELLOCLUSTER.PINGALL */
int PingallCommand_RedisCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
REDISMODULE_NOT_USED(argv);
REDISMODULE_NOT_USED(argc);
RedisModule_SendClusterMessage(ctx,NULL,MSGTYPE_PING,"Hey",3);
return RedisModule_ReplyWithSimpleString(ctx, "OK");
}
/* HELLOCLUSTER.LIST */
int ListCommand_RedisCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
REDISMODULE_NOT_USED(argv);
REDISMODULE_NOT_USED(argc);
size_t numnodes;
char **ids = RedisModule_GetClusterNodesList(ctx,&numnodes);
if (ids == NULL) {
return RedisModule_ReplyWithError(ctx,"Cluster not enabled");
}
RedisModule_ReplyWithArray(ctx,numnodes);
for (size_t j = 0; j < numnodes; j++) {
int port;
RedisModule_GetClusterNodeInfo(ctx,ids[j],NULL,NULL,&port,NULL);
RedisModule_ReplyWithArray(ctx,2);
RedisModule_ReplyWithStringBuffer(ctx,ids[j],REDISMODULE_NODE_ID_LEN);
RedisModule_ReplyWithLongLong(ctx,port);
}
RedisModule_FreeClusterNodesList(ids);
return REDISMODULE_OK;
}
/* Callback for message MSGTYPE_PING */
void PingReceiver(RedisModuleCtx *ctx, const char *sender_id, uint8_t type, const unsigned char *payload, uint32_t len) {
RedisModule_Log(ctx,"notice","PING (type %d) RECEIVED from %.*s: '%.*s'",
type,REDISMODULE_NODE_ID_LEN,sender_id,(int)len, payload);
RedisModule_SendClusterMessage(ctx,NULL,MSGTYPE_PONG,"Ohi!",4);
RedisModuleCallReply *reply = RedisModule_Call(ctx, "INCR", "c", "pings_received");
RedisModule_FreeCallReply(reply);
}
/* Callback for message MSGTYPE_PONG. */
void PongReceiver(RedisModuleCtx *ctx, const char *sender_id, uint8_t type, const unsigned char *payload, uint32_t len) {
RedisModule_Log(ctx,"notice","PONG (type %d) RECEIVED from %.*s: '%.*s'",
type,REDISMODULE_NODE_ID_LEN,sender_id,(int)len, payload);
}
/* This function must be present on each Redis module. It is used in order to
* register the commands into the Redis server. */
int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
REDISMODULE_NOT_USED(argv);
REDISMODULE_NOT_USED(argc);
if (RedisModule_Init(ctx,"hellocluster",1,REDISMODULE_APIVER_1)
== REDISMODULE_ERR) return REDISMODULE_ERR;
if (RedisModule_CreateCommand(ctx,"hellocluster.pingall",
PingallCommand_RedisCommand,"readonly",0,0,0) == REDISMODULE_ERR)
return REDISMODULE_ERR;
if (RedisModule_CreateCommand(ctx,"hellocluster.list",
ListCommand_RedisCommand,"readonly",0,0,0) == REDISMODULE_ERR)
return REDISMODULE_ERR;
/* Disable Redis Cluster sharding and redirections. This way every node
* will be able to access every possible key, regardless of the hash slot.
* This way the PING message handler will be able to increment a specific
* variable. Normally you do that in order for the distributed system
* you create as a module to have total freedom in the keyspace
* manipulation. */
RedisModule_SetClusterFlags(ctx,REDISMODULE_CLUSTER_FLAG_NO_REDIRECTION);
/* Register our handlers for different message types. */
RedisModule_RegisterClusterMessageReceiver(ctx,MSGTYPE_PING,PingReceiver);
RedisModule_RegisterClusterMessageReceiver(ctx,MSGTYPE_PONG,PongReceiver);
return REDISMODULE_OK;
}
|