1 files changed, 118 insertions, 0 deletions
diff --git a/src/modules/hellocluster.c b/src/modules/hellocluster.c
new file mode 100644
index 0000000..bc145c2
--- /dev/null
+++ b/src/modules/hellocluster.c
@@ -0,0 +1,118 @@
+/* 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;
+}