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#include "redismodule.h"
#include <string.h>
#include <assert.h>
#include <unistd.h>
typedef struct {
size_t nkeys;
} scan_strings_pd;
void scan_strings_callback(RedisModuleCtx *ctx, RedisModuleString* keyname, RedisModuleKey* key, void *privdata) {
scan_strings_pd* pd = privdata;
int was_opened = 0;
if (!key) {
key = RedisModule_OpenKey(ctx, keyname, REDISMODULE_READ);
was_opened = 1;
}
if (RedisModule_KeyType(key) == REDISMODULE_KEYTYPE_STRING) {
size_t len;
char * data = RedisModule_StringDMA(key, &len, REDISMODULE_READ);
RedisModule_ReplyWithArray(ctx, 2);
RedisModule_ReplyWithString(ctx, keyname);
RedisModule_ReplyWithStringBuffer(ctx, data, len);
pd->nkeys++;
}
if (was_opened)
RedisModule_CloseKey(key);
}
int scan_strings(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
{
REDISMODULE_NOT_USED(argv);
REDISMODULE_NOT_USED(argc);
scan_strings_pd pd = {
.nkeys = 0,
};
RedisModule_ReplyWithArray(ctx, REDISMODULE_POSTPONED_LEN);
RedisModuleScanCursor* cursor = RedisModule_ScanCursorCreate();
while(RedisModule_Scan(ctx, cursor, scan_strings_callback, &pd));
RedisModule_ScanCursorDestroy(cursor);
RedisModule_ReplySetArrayLength(ctx, pd.nkeys);
return REDISMODULE_OK;
}
typedef struct {
RedisModuleCtx *ctx;
size_t nreplies;
} scan_key_pd;
void scan_key_callback(RedisModuleKey *key, RedisModuleString* field, RedisModuleString* value, void *privdata) {
REDISMODULE_NOT_USED(key);
scan_key_pd* pd = privdata;
RedisModule_ReplyWithArray(pd->ctx, 2);
size_t fieldCStrLen;
// The implementation of RedisModuleString is robj with lots of encodings.
// We want to make sure the robj that passes to this callback in
// String encoded, this is why we use RedisModule_StringPtrLen and
// RedisModule_ReplyWithStringBuffer instead of directly use
// RedisModule_ReplyWithString.
const char* fieldCStr = RedisModule_StringPtrLen(field, &fieldCStrLen);
RedisModule_ReplyWithStringBuffer(pd->ctx, fieldCStr, fieldCStrLen);
if(value){
size_t valueCStrLen;
const char* valueCStr = RedisModule_StringPtrLen(value, &valueCStrLen);
RedisModule_ReplyWithStringBuffer(pd->ctx, valueCStr, valueCStrLen);
} else {
RedisModule_ReplyWithNull(pd->ctx);
}
pd->nreplies++;
}
int scan_key(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
{
if (argc != 2) {
RedisModule_WrongArity(ctx);
return REDISMODULE_OK;
}
scan_key_pd pd = {
.ctx = ctx,
.nreplies = 0,
};
RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_READ);
if (!key) {
RedisModule_ReplyWithError(ctx, "not found");
return REDISMODULE_OK;
}
RedisModule_ReplyWithArray(ctx, REDISMODULE_POSTPONED_ARRAY_LEN);
RedisModuleScanCursor* cursor = RedisModule_ScanCursorCreate();
while(RedisModule_ScanKey(key, cursor, scan_key_callback, &pd));
RedisModule_ScanCursorDestroy(cursor);
RedisModule_ReplySetArrayLength(ctx, pd.nreplies);
RedisModule_CloseKey(key);
return REDISMODULE_OK;
}
int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
REDISMODULE_NOT_USED(argv);
REDISMODULE_NOT_USED(argc);
if (RedisModule_Init(ctx, "scan", 1, REDISMODULE_APIVER_1)== REDISMODULE_ERR)
return REDISMODULE_ERR;
if (RedisModule_CreateCommand(ctx, "scan.scan_strings", scan_strings, "", 0, 0, 0) == REDISMODULE_ERR)
return REDISMODULE_ERR;
if (RedisModule_CreateCommand(ctx, "scan.scan_key", scan_key, "", 0, 0, 0) == REDISMODULE_ERR)
return REDISMODULE_ERR;
return REDISMODULE_OK;
}
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