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#include <adapters/valkeymoduleapi.h>
#include <async.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <valkey.h>
void debugCallback(valkeyAsyncContext *c, void *r, void *privdata) {
(void)privdata; //unused
valkeyReply *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)*/
valkeyAsyncDisconnect(c);
}
void getCallback(valkeyAsyncContext *c, void *r, void *privdata) {
valkeyReply *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 */
valkeyAsyncCommand(c, debugCallback, NULL, "DEBUG SLEEP %f", 1.5);
}
void connectCallback(valkeyAsyncContext *c, int status) {
if (status != VALKEY_OK) {
printf("Error: %s\n", c->errstr);
return;
}
printf("Connected...\n");
}
void disconnectCallback(const valkeyAsyncContext *c, int status) {
if (status != VALKEY_OK) {
printf("Error: %s\n", c->errstr);
return;
}
printf("Disconnected...\n");
}
/*
* 1- Compile this file as a shared library. Directory of "valkeymodule.h" must
* be in the include path.
* gcc -fPIC -shared -I../../valkey/src/ -I.. example-valkeymoduleapi.c -o example-valkeymoduleapi.so
*
* 2- Load module:
* valkey-server --loadmodule ./example-valkeymoduleapi.so value
*/
int ValkeyModule_OnLoad(ValkeyModuleCtx *ctx, ValkeyModuleString **argv, int argc) {
int ret = ValkeyModule_Init(ctx, "example-valkeymoduleapi", 1, VALKEYMODULE_APIVER_1);
if (ret != VALKEYMODULE_OK) {
printf("error module init \n");
return VALKEYMODULE_ERR;
}
valkeyAsyncContext *c = valkeyAsyncConnect("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 = ValkeyModule_StringPtrLen(argv[argc - 1], &len);
ValkeyModuleCtx *module_ctx = ValkeyModule_GetDetachedThreadSafeContext(ctx);
valkeyModuleAttach(c, module_ctx);
valkeyAsyncSetConnectCallback(c, connectCallback);
valkeyAsyncSetDisconnectCallback(c, disconnectCallback);
valkeyAsyncSetTimeout(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`.
*/
valkeyAsyncCommand(c, NULL, NULL, "SET key %b", val, len);
valkeyAsyncCommand(c, getCallback, (char *)"end-1", "GET key");
return 0;
}
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