漫话Redis源码之九十七

本文主要是介绍漫话Redis源码之九十七，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

这里都是Event相关的代码，非核心内容，不用细看：

#include "redismodule.h"
#include <stdio.h>
#include <string.h>/* We need to store events to be able to test and see what we got, and we can't* store them in the key-space since that would mess up rdb loading (duplicates)* and be lost of flushdb. */
RedisModuleDict *event_log = NULL;typedef struct EventElement {long count;RedisModuleString *last_val_string;long last_val_int;
} EventElement;void LogStringEvent(RedisModuleCtx *ctx, const char* keyname, const char* data) {EventElement *event = RedisModule_DictGetC(event_log, (void*)keyname, strlen(keyname), NULL);if (!event) {event = RedisModule_Alloc(sizeof(EventElement));memset(event, 0, sizeof(EventElement));RedisModule_DictSetC(event_log, (void*)keyname, strlen(keyname), event);}if (event->last_val_string) RedisModule_FreeString(ctx, event->last_val_string);event->last_val_string = RedisModule_CreateString(ctx, data, strlen(data));event->count++;
}void LogNumericEvent(RedisModuleCtx *ctx, const char* keyname, long data) {REDISMODULE_NOT_USED(ctx);EventElement *event = RedisModule_DictGetC(event_log, (void*)keyname, strlen(keyname), NULL);if (!event) {event = RedisModule_Alloc(sizeof(EventElement));memset(event, 0, sizeof(EventElement));RedisModule_DictSetC(event_log, (void*)keyname, strlen(keyname), event);}event->last_val_int = data;event->count++;
}void FreeEvent(RedisModuleCtx *ctx, EventElement *event) {if (event->last_val_string)RedisModule_FreeString(ctx, event->last_val_string);RedisModule_Free(event);
}int cmdEventCount(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
{if (argc != 2){RedisModule_WrongArity(ctx);return REDISMODULE_OK;}EventElement *event = RedisModule_DictGet(event_log, argv[1], NULL);RedisModule_ReplyWithLongLong(ctx, event? event->count: 0);return REDISMODULE_OK;
}int cmdEventLast(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
{if (argc != 2){RedisModule_WrongArity(ctx);return REDISMODULE_OK;}EventElement *event = RedisModule_DictGet(event_log, argv[1], NULL);if (event && event->last_val_string)RedisModule_ReplyWithString(ctx, event->last_val_string);else if (event)RedisModule_ReplyWithLongLong(ctx, event->last_val_int);elseRedisModule_ReplyWithNull(ctx);return REDISMODULE_OK;
}void clearEvents(RedisModuleCtx *ctx)
{RedisModuleString *key;EventElement *event;RedisModuleDictIter *iter = RedisModule_DictIteratorStart(event_log, "^", NULL);while((key = RedisModule_DictNext(ctx, iter, (void**)&event)) != NULL) {event->count = 0;event->last_val_int = 0;if (event->last_val_string) RedisModule_FreeString(ctx, event->last_val_string);event->last_val_string = NULL;RedisModule_DictDel(event_log, key, NULL);RedisModule_Free(event);}RedisModule_DictIteratorStop(iter);
}int cmdEventsClear(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
{REDISMODULE_NOT_USED(argc);REDISMODULE_NOT_USED(argv);clearEvents(ctx);return REDISMODULE_OK;
}/* Client state change callback. */
void clientChangeCallback(RedisModuleCtx *ctx, RedisModuleEvent e, uint64_t sub, void *data)
{REDISMODULE_NOT_USED(e);RedisModuleClientInfo *ci = data;char *keyname = (sub == REDISMODULE_SUBEVENT_CLIENT_CHANGE_CONNECTED) ?"client-connected" : "client-disconnected";LogNumericEvent(ctx, keyname, ci->id);
}void flushdbCallback(RedisModuleCtx *ctx, RedisModuleEvent e, uint64_t sub, void *data)
{REDISMODULE_NOT_USED(e);RedisModuleFlushInfo *fi = data;char *keyname = (sub == REDISMODULE_SUBEVENT_FLUSHDB_START) ?"flush-start" : "flush-end";LogNumericEvent(ctx, keyname, fi->dbnum);
}void roleChangeCallback(RedisModuleCtx *ctx, RedisModuleEvent e, uint64_t sub, void *data)
{REDISMODULE_NOT_USED(e);REDISMODULE_NOT_USED(data);RedisModuleReplicationInfo *ri = data;char *keyname = (sub == REDISMODULE_EVENT_REPLROLECHANGED_NOW_MASTER) ?"role-master" : "role-replica";LogStringEvent(ctx, keyname, ri->masterhost);
}void replicationChangeCallback(RedisModuleCtx *ctx, RedisModuleEvent e, uint64_t sub, void *data)
{REDISMODULE_NOT_USED(e);REDISMODULE_NOT_USED(data);char *keyname = (sub == REDISMODULE_SUBEVENT_REPLICA_CHANGE_ONLINE) ?"replica-online" : "replica-offline";LogNumericEvent(ctx, keyname, 0);
}void rasterLinkChangeCallback(RedisModuleCtx *ctx, RedisModuleEvent e, uint64_t sub, void *data)
{REDISMODULE_NOT_USED(e);REDISMODULE_NOT_USED(data);char *keyname = (sub == REDISMODULE_SUBEVENT_MASTER_LINK_UP) ?"masterlink-up" : "masterlink-down";LogNumericEvent(ctx, keyname, 0);
}void persistenceCallback(RedisModuleCtx *ctx, RedisModuleEvent e, uint64_t sub, void *data)
{REDISMODULE_NOT_USED(e);REDISMODULE_NOT_USED(data);char *keyname = NULL;switch (sub) {case REDISMODULE_SUBEVENT_PERSISTENCE_RDB_START: keyname = "persistence-rdb-start"; break;case REDISMODULE_SUBEVENT_PERSISTENCE_AOF_START: keyname = "persistence-aof-start"; break;case REDISMODULE_SUBEVENT_PERSISTENCE_SYNC_RDB_START: keyname = "persistence-syncrdb-start"; break;case REDISMODULE_SUBEVENT_PERSISTENCE_ENDED: keyname = "persistence-end"; break;case REDISMODULE_SUBEVENT_PERSISTENCE_FAILED: keyname = "persistence-failed"; break;}/* modifying the keyspace from the fork child is not an option, using log instead */RedisModule_Log(ctx, "warning", "module-event-%s", keyname);if (sub == REDISMODULE_SUBEVENT_PERSISTENCE_SYNC_RDB_START)LogNumericEvent(ctx, keyname, 0);
}void loadingCallback(RedisModuleCtx *ctx, RedisModuleEvent e, uint64_t sub, void *data)
{REDISMODULE_NOT_USED(e);REDISMODULE_NOT_USED(data);char *keyname = NULL;switch (sub) {case REDISMODULE_SUBEVENT_LOADING_RDB_START: keyname = "loading-rdb-start"; break;case REDISMODULE_SUBEVENT_LOADING_AOF_START: keyname = "loading-aof-start"; break;case REDISMODULE_SUBEVENT_LOADING_REPL_START: keyname = "loading-repl-start"; break;case REDISMODULE_SUBEVENT_LOADING_ENDED: keyname = "loading-end"; break;case REDISMODULE_SUBEVENT_LOADING_FAILED: keyname = "loading-failed"; break;}LogNumericEvent(ctx, keyname, 0);
}void loadingProgressCallback(RedisModuleCtx *ctx, RedisModuleEvent e, uint64_t sub, void *data)
{REDISMODULE_NOT_USED(e);RedisModuleLoadingProgress *ei = data;char *keyname = (sub == REDISMODULE_SUBEVENT_LOADING_PROGRESS_RDB) ?"loading-progress-rdb" : "loading-progress-aof";LogNumericEvent(ctx, keyname, ei->progress);
}void shutdownCallback(RedisModuleCtx *ctx, RedisModuleEvent e, uint64_t sub, void *data)
{REDISMODULE_NOT_USED(e);REDISMODULE_NOT_USED(data);REDISMODULE_NOT_USED(sub);RedisModule_Log(ctx, "warning", "module-event-%s", "shutdown");
}void cronLoopCallback(RedisModuleCtx *ctx, RedisModuleEvent e, uint64_t sub, void *data)
{REDISMODULE_NOT_USED(e);REDISMODULE_NOT_USED(sub);RedisModuleCronLoop *ei = data;LogNumericEvent(ctx, "cron-loop", ei->hz);
}void moduleChangeCallback(RedisModuleCtx *ctx, RedisModuleEvent e, uint64_t sub, void *data)
{REDISMODULE_NOT_USED(e);RedisModuleModuleChange *ei = data;char *keyname = (sub == REDISMODULE_SUBEVENT_MODULE_LOADED) ?"module-loaded" : "module-unloaded";LogStringEvent(ctx, keyname, ei->module_name);
}void swapDbCallback(RedisModuleCtx *ctx, RedisModuleEvent e, uint64_t sub, void *data)
{REDISMODULE_NOT_USED(e);REDISMODULE_NOT_USED(sub);RedisModuleSwapDbInfo *ei = data;LogNumericEvent(ctx, "swapdb-first", ei->dbnum_first);LogNumericEvent(ctx, "swapdb-second", ei->dbnum_second);
}/* 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) {
#define VerifySubEventSupported(e, s) \if (!RedisModule_IsSubEventSupported(e, s)) { \return REDISMODULE_ERR; \}REDISMODULE_NOT_USED(argv);REDISMODULE_NOT_USED(argc);if (RedisModule_Init(ctx,"testhook",1,REDISMODULE_APIVER_1)== REDISMODULE_ERR) return REDISMODULE_ERR;/* Example on how to check if a server sub event is supported */if (!RedisModule_IsSubEventSupported(RedisModuleEvent_ReplicationRoleChanged, REDISMODULE_EVENT_REPLROLECHANGED_NOW_MASTER)) {return REDISMODULE_ERR;}/* replication related hooks */RedisModule_SubscribeToServerEvent(ctx,RedisModuleEvent_ReplicationRoleChanged, roleChangeCallback);RedisModule_SubscribeToServerEvent(ctx,RedisModuleEvent_ReplicaChange, replicationChangeCallback);RedisModule_SubscribeToServerEvent(ctx,RedisModuleEvent_MasterLinkChange, rasterLinkChangeCallback);/* persistence related hooks */RedisModule_SubscribeToServerEvent(ctx,RedisModuleEvent_Persistence, persistenceCallback);RedisModule_SubscribeToServerEvent(ctx,RedisModuleEvent_Loading, loadingCallback);RedisModule_SubscribeToServerEvent(ctx,RedisModuleEvent_LoadingProgress, loadingProgressCallback);/* other hooks */RedisModule_SubscribeToServerEvent(ctx,RedisModuleEvent_ClientChange, clientChangeCallback);RedisModule_SubscribeToServerEvent(ctx,RedisModuleEvent_FlushDB, flushdbCallback);RedisModule_SubscribeToServerEvent(ctx,RedisModuleEvent_Shutdown, shutdownCallback);RedisModule_SubscribeToServerEvent(ctx,RedisModuleEvent_CronLoop, cronLoopCallback);RedisModule_SubscribeToServerEvent(ctx,RedisModuleEvent_ModuleChange, moduleChangeCallback);RedisModule_SubscribeToServerEvent(ctx,RedisModuleEvent_SwapDB, swapDbCallback);event_log = RedisModule_CreateDict(ctx);if (RedisModule_CreateCommand(ctx,"hooks.event_count", cmdEventCount,"",0,0,0) == REDISMODULE_ERR)return REDISMODULE_ERR;if (RedisModule_CreateCommand(ctx,"hooks.event_last", cmdEventLast,"",0,0,0) == REDISMODULE_ERR)return REDISMODULE_ERR;if (RedisModule_CreateCommand(ctx,"hooks.clear", cmdEventsClear,"",0,0,0) == REDISMODULE_ERR)return REDISMODULE_ERR;return REDISMODULE_OK;
}int RedisModule_OnUnload(RedisModuleCtx *ctx) {clearEvents(ctx);RedisModule_FreeDict(ctx, event_log);event_log = NULL;return REDISMODULE_OK;
}

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