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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>
#include <hiredis.h>
#include <async.h>
#include <adapters/redismoduleapi.h>
void debugCallback(redisAsyncContext *c, void *r, void *privdata) {
(void)privdata; //unused
redisReply *reply = r;
if (reply == NULL) {
/* The DEBUG SLEEP command will almost always fail, because we have set a 1 second timeout */
printf("`DEBUG SLEEP` error: %s\n", c->errstr ? c->errstr : "unknown error");
return;
}
/* Disconnect after receiving the reply of DEBUG SLEEP (which will not)*/
redisAsyncDisconnect(c);
}
void getCallback(redisAsyncContext *c, void *r, void *privdata) {
redisReply *reply = r;
if (reply == NULL) {
if (c->errstr) {
printf("errstr: %s\n", c->errstr);
}
return;
}
printf("argv[%s]: %s\n", (char*)privdata, reply->str);
/* start another request that demonstrate timeout */
redisAsyncCommand(c, debugCallback, NULL, "DEBUG SLEEP %f", 1.5);
}
void connectCallback(const redisAsyncContext *c, int status) {
if (status != REDIS_OK) {
printf("Error: %s\n", c->errstr);
return;
}
printf("Connected...\n");
}
void disconnectCallback(const redisAsyncContext *c, int status) {
if (status != REDIS_OK) {
printf("Error: %s\n", c->errstr);
return;
}
printf("Disconnected...\n");
}
/*
* This example requires Redis 7.0 or above.
*
* 1- Compile this file as a shared library. Directory of "redismodule.h" must
* be in the include path.
* gcc -fPIC -shared -I../../redis/src/ -I.. example-redismoduleapi.c -o example-redismoduleapi.so
*
* 2- Load module:
* redis-server --loadmodule ./example-redismoduleapi.so value
*/
int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
int ret = RedisModule_Init(ctx, "example-redismoduleapi", 1, REDISMODULE_APIVER_1);
if (ret != REDISMODULE_OK) {
printf("error module init \n");
return REDISMODULE_ERR;
}
if (redisModuleCompatibilityCheck() != REDIS_OK) {
printf("Redis 7.0 or above is required! \n");
return REDISMODULE_ERR;
}
redisAsyncContext *c = redisAsyncConnect("127.0.0.1", 6379);
if (c->err) {
/* Let *c leak for now... */
printf("Error: %s\n", c->errstr);
return 1;
}
size_t len;
const char *val = RedisModule_StringPtrLen(argv[argc-1], &len);
RedisModuleCtx *module_ctx = RedisModule_GetDetachedThreadSafeContext(ctx);
redisModuleAttach(c, module_ctx);
redisAsyncSetConnectCallback(c,connectCallback);
redisAsyncSetDisconnectCallback(c,disconnectCallback);
redisAsyncSetTimeout(c, (struct timeval){ .tv_sec = 1, .tv_usec = 0});
/*
In this demo, we first `set key`, then `get key` to demonstrate the basic usage of the adapter.
Then in `getCallback`, we start a `debug sleep` command to create 1.5 second long request.
Because we have set a 1 second timeout to the connection, the command will always fail with a
timeout error, which is shown in the `debugCallback`.
*/
redisAsyncCommand(c, NULL, NULL, "SET key %b", val, len);
redisAsyncCommand(c, getCallback, (char*)"end-1", "GET key");
return 0;
}
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