redict/tests/modules/postnotifications.c
2024-03-21 14:30:47 +01:00

284 lines
11 KiB
C

// Copyright (c) 2020, Meir Shpilraien <meir at redislabs dot com>
// SPDX-FileCopyrightText: 2024 Redict Contributors
// SPDX-FileCopyrightText: 2024 Salvatore Sanfilippo <antirez at gmail dot com>
//
// SPDX-License-Identifier: BSD-3-Clause
// SPDX-License-Identifier: GPL-3.0-only
/* This module allow to verify 'RedisModule_AddPostNotificationJob' by registering to 3
* key space event:
* * STRINGS - the module register to all strings notifications and set post notification job
* that increase a counter indicating how many times the string key was changed.
* In addition, it increase another counter that counts the total changes that
* was made on all strings keys.
* * EXPIRED - the module register to expired event and set post notification job that that
* counts the total number of expired events.
* * EVICTED - the module register to evicted event and set post notification job that that
* counts the total number of evicted events.
*
* In addition, the module register a new command, 'postnotification.async_set', that performs a set
* command from a background thread. This allows to check the 'RedisModule_AddPostNotificationJob' on
* notifications that was triggered on a background thread. */
#define _BSD_SOURCE
#define _DEFAULT_SOURCE /* For usleep */
#include "redictmodule.h"
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <pthread.h>
static void KeySpace_PostNotificationStringFreePD(void *pd) {
RedisModule_FreeString(NULL, pd);
}
static void KeySpace_PostNotificationReadKey(RedisModuleCtx *ctx, void *pd) {
RedisModuleCallReply* rep = RedisModule_Call(ctx, "get", "!s", pd);
RedisModule_FreeCallReply(rep);
}
static void KeySpace_PostNotificationString(RedisModuleCtx *ctx, void *pd) {
REDISMODULE_NOT_USED(ctx);
RedisModuleCallReply* rep = RedisModule_Call(ctx, "incr", "!s", pd);
RedisModule_FreeCallReply(rep);
}
static int KeySpace_NotificationExpired(RedisModuleCtx *ctx, int type, const char *event, RedisModuleString *key){
REDISMODULE_NOT_USED(type);
REDISMODULE_NOT_USED(event);
REDISMODULE_NOT_USED(key);
RedisModuleString *new_key = RedisModule_CreateString(NULL, "expired", 7);
int res = RedisModule_AddPostNotificationJob(ctx, KeySpace_PostNotificationString, new_key, KeySpace_PostNotificationStringFreePD);
if (res == REDISMODULE_ERR) KeySpace_PostNotificationStringFreePD(new_key);
return REDISMODULE_OK;
}
static int KeySpace_NotificationEvicted(RedisModuleCtx *ctx, int type, const char *event, RedisModuleString *key){
REDISMODULE_NOT_USED(type);
REDISMODULE_NOT_USED(event);
REDISMODULE_NOT_USED(key);
const char *key_str = RedisModule_StringPtrLen(key, NULL);
if (strncmp(key_str, "evicted", 7) == 0) {
return REDISMODULE_OK; /* do not count the evicted key */
}
if (strncmp(key_str, "before_evicted", 14) == 0) {
return REDISMODULE_OK; /* do not count the before_evicted key */
}
RedisModuleString *new_key = RedisModule_CreateString(NULL, "evicted", 7);
int res = RedisModule_AddPostNotificationJob(ctx, KeySpace_PostNotificationString, new_key, KeySpace_PostNotificationStringFreePD);
if (res == REDISMODULE_ERR) KeySpace_PostNotificationStringFreePD(new_key);
return REDISMODULE_OK;
}
static int KeySpace_NotificationString(RedisModuleCtx *ctx, int type, const char *event, RedisModuleString *key){
REDISMODULE_NOT_USED(ctx);
REDISMODULE_NOT_USED(type);
REDISMODULE_NOT_USED(event);
const char *key_str = RedisModule_StringPtrLen(key, NULL);
if (strncmp(key_str, "string_", 7) != 0) {
return REDISMODULE_OK;
}
if (strcmp(key_str, "string_total") == 0) {
return REDISMODULE_OK;
}
RedisModuleString *new_key;
if (strncmp(key_str, "string_changed{", 15) == 0) {
new_key = RedisModule_CreateString(NULL, "string_total", 12);
} else {
new_key = RedisModule_CreateStringPrintf(NULL, "string_changed{%s}", key_str);
}
int res = RedisModule_AddPostNotificationJob(ctx, KeySpace_PostNotificationString, new_key, KeySpace_PostNotificationStringFreePD);
if (res == REDISMODULE_ERR) KeySpace_PostNotificationStringFreePD(new_key);
return REDISMODULE_OK;
}
static int KeySpace_LazyExpireInsidePostNotificationJob(RedisModuleCtx *ctx, int type, const char *event, RedisModuleString *key){
REDISMODULE_NOT_USED(ctx);
REDISMODULE_NOT_USED(type);
REDISMODULE_NOT_USED(event);
const char *key_str = RedisModule_StringPtrLen(key, NULL);
if (strncmp(key_str, "read_", 5) != 0) {
return REDISMODULE_OK;
}
RedisModuleString *new_key = RedisModule_CreateString(NULL, key_str + 5, strlen(key_str) - 5);;
int res = RedisModule_AddPostNotificationJob(ctx, KeySpace_PostNotificationReadKey, new_key, KeySpace_PostNotificationStringFreePD);
if (res == REDISMODULE_ERR) KeySpace_PostNotificationStringFreePD(new_key);
return REDISMODULE_OK;
}
static int KeySpace_NestedNotification(RedisModuleCtx *ctx, int type, const char *event, RedisModuleString *key){
REDISMODULE_NOT_USED(ctx);
REDISMODULE_NOT_USED(type);
REDISMODULE_NOT_USED(event);
const char *key_str = RedisModule_StringPtrLen(key, NULL);
if (strncmp(key_str, "write_sync_", 11) != 0) {
return REDISMODULE_OK;
}
/* This test was only meant to check REDISMODULE_OPTIONS_ALLOW_NESTED_KEYSPACE_NOTIFICATIONS.
* In general it is wrong and discourage to perform any writes inside a notification callback. */
RedisModuleString *new_key = RedisModule_CreateString(NULL, key_str + 11, strlen(key_str) - 11);;
RedisModuleCallReply* rep = RedisModule_Call(ctx, "set", "!sc", new_key, "1");
RedisModule_FreeCallReply(rep);
RedisModule_FreeString(NULL, new_key);
return REDISMODULE_OK;
}
static void *KeySpace_PostNotificationsAsyncSetInner(void *arg) {
RedisModuleBlockedClient *bc = arg;
RedisModuleCtx *ctx = RedisModule_GetThreadSafeContext(bc);
RedisModule_ThreadSafeContextLock(ctx);
RedisModuleCallReply* rep = RedisModule_Call(ctx, "set", "!cc", "string_x", "1");
RedisModule_ThreadSafeContextUnlock(ctx);
RedisModule_ReplyWithCallReply(ctx, rep);
RedisModule_FreeCallReply(rep);
RedisModule_UnblockClient(bc, NULL);
RedisModule_FreeThreadSafeContext(ctx);
return NULL;
}
static int KeySpace_PostNotificationsAsyncSet(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
REDISMODULE_NOT_USED(argv);
if (argc != 1)
return RedisModule_WrongArity(ctx);
pthread_t tid;
RedisModuleBlockedClient *bc = RedisModule_BlockClient(ctx,NULL,NULL,NULL,0);
if (pthread_create(&tid,NULL,KeySpace_PostNotificationsAsyncSetInner,bc) != 0) {
RedisModule_AbortBlock(bc);
return RedisModule_ReplyWithError(ctx,"-ERR Can't start thread");
}
return REDISMODULE_OK;
}
typedef struct KeySpace_EventPostNotificationCtx {
RedisModuleString *triggered_on;
RedisModuleString *new_key;
} KeySpace_EventPostNotificationCtx;
static void KeySpace_ServerEventPostNotificationFree(void *pd) {
KeySpace_EventPostNotificationCtx *pn_ctx = pd;
RedisModule_FreeString(NULL, pn_ctx->new_key);
RedisModule_FreeString(NULL, pn_ctx->triggered_on);
RedisModule_Free(pn_ctx);
}
static void KeySpace_ServerEventPostNotification(RedisModuleCtx *ctx, void *pd) {
REDISMODULE_NOT_USED(ctx);
KeySpace_EventPostNotificationCtx *pn_ctx = pd;
RedisModuleCallReply* rep = RedisModule_Call(ctx, "lpush", "!ss", pn_ctx->new_key, pn_ctx->triggered_on);
RedisModule_FreeCallReply(rep);
}
static void KeySpace_ServerEventCallback(RedisModuleCtx *ctx, RedisModuleEvent eid, uint64_t subevent, void *data) {
REDISMODULE_NOT_USED(eid);
REDISMODULE_NOT_USED(data);
if (subevent > 3) {
RedisModule_Log(ctx, "warning", "Got an unexpected subevent '%llu'", (unsigned long long)subevent);
return;
}
static const char* events[] = {
"before_deleted",
"before_expired",
"before_evicted",
"before_overwritten",
};
const RedisModuleString *key_name = RedisModule_GetKeyNameFromModuleKey(((RedisModuleKeyInfo*)data)->key);
const char *key_str = RedisModule_StringPtrLen(key_name, NULL);
for (int i = 0 ; i < 4 ; ++i) {
const char *event = events[i];
if (strncmp(key_str, event , strlen(event)) == 0) {
return; /* don't log any event on our tracking keys */
}
}
KeySpace_EventPostNotificationCtx *pn_ctx = RedisModule_Alloc(sizeof(*pn_ctx));
pn_ctx->triggered_on = RedisModule_HoldString(NULL, (RedisModuleString*)key_name);
pn_ctx->new_key = RedisModule_CreateString(NULL, events[subevent], strlen(events[subevent]));
int res = RedisModule_AddPostNotificationJob(ctx, KeySpace_ServerEventPostNotification, pn_ctx, KeySpace_ServerEventPostNotificationFree);
if (res == REDISMODULE_ERR) KeySpace_ServerEventPostNotificationFree(pn_ctx);
}
/* 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,"postnotifications",1,REDISMODULE_APIVER_1) == REDISMODULE_ERR){
return REDISMODULE_ERR;
}
if (!(RedisModule_GetModuleOptionsAll() & REDISMODULE_OPTIONS_ALLOW_NESTED_KEYSPACE_NOTIFICATIONS)) {
return REDISMODULE_ERR;
}
int with_key_events = 0;
if (argc >= 1) {
const char *arg = RedisModule_StringPtrLen(argv[0], 0);
if (strcmp(arg, "with_key_events") == 0) {
with_key_events = 1;
}
}
RedisModule_SetModuleOptions(ctx, REDISMODULE_OPTIONS_ALLOW_NESTED_KEYSPACE_NOTIFICATIONS);
if(RedisModule_SubscribeToKeyspaceEvents(ctx, REDISMODULE_NOTIFY_STRING, KeySpace_NotificationString) != REDISMODULE_OK){
return REDISMODULE_ERR;
}
if(RedisModule_SubscribeToKeyspaceEvents(ctx, REDISMODULE_NOTIFY_STRING, KeySpace_LazyExpireInsidePostNotificationJob) != REDISMODULE_OK){
return REDISMODULE_ERR;
}
if(RedisModule_SubscribeToKeyspaceEvents(ctx, REDISMODULE_NOTIFY_STRING, KeySpace_NestedNotification) != REDISMODULE_OK){
return REDISMODULE_ERR;
}
if(RedisModule_SubscribeToKeyspaceEvents(ctx, REDISMODULE_NOTIFY_EXPIRED, KeySpace_NotificationExpired) != REDISMODULE_OK){
return REDISMODULE_ERR;
}
if(RedisModule_SubscribeToKeyspaceEvents(ctx, REDISMODULE_NOTIFY_EVICTED, KeySpace_NotificationEvicted) != REDISMODULE_OK){
return REDISMODULE_ERR;
}
if (with_key_events) {
if(RedisModule_SubscribeToServerEvent(ctx, RedisModuleEvent_Key, KeySpace_ServerEventCallback) != REDISMODULE_OK){
return REDISMODULE_ERR;
}
}
if (RedisModule_CreateCommand(ctx, "postnotification.async_set", KeySpace_PostNotificationsAsyncSet,
"write", 0, 0, 0) == REDISMODULE_ERR){
return REDISMODULE_ERR;
}
return REDISMODULE_OK;
}
int RedisModule_OnUnload(RedisModuleCtx *ctx) {
REDISMODULE_NOT_USED(ctx);
return REDISMODULE_OK;
}