valkey/tests/modules/getkeys.c
Yossi Gottlieb 7d117d7591 Modules: add RM_GetCommandKeys().
This is essentially the same as calling COMMAND GETKEYS but provides a
more efficient interface that can be used in every context (i.e. not a
Redis command).
2020-10-11 16:04:14 +03:00

126 lines
3.6 KiB
C

#define REDISMODULE_EXPERIMENTAL_API
#include "redismodule.h"
#include <strings.h>
#include <assert.h>
#include <unistd.h>
#include <errno.h>
#define UNUSED(V) ((void) V)
/* A sample movable keys command that returns a list of all
* arguments that follow a KEY argument, i.e.
*/
int getkeys_command(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
{
int i;
int count = 0;
/* Handle getkeys-api introspection */
if (RedisModule_IsKeysPositionRequest(ctx)) {
for (i = 0; i < argc; i++) {
size_t len;
const char *str = RedisModule_StringPtrLen(argv[i], &len);
if (len == 3 && !strncasecmp(str, "key", 3) && i + 1 < argc)
RedisModule_KeyAtPos(ctx, i + 1);
}
return REDISMODULE_OK;
}
/* Handle real command invocation */
RedisModule_ReplyWithArray(ctx, REDISMODULE_POSTPONED_ARRAY_LEN);
for (i = 0; i < argc; i++) {
size_t len;
const char *str = RedisModule_StringPtrLen(argv[i], &len);
if (len == 3 && !strncasecmp(str, "key", 3) && i + 1 < argc) {
RedisModule_ReplyWithString(ctx, argv[i+1]);
count++;
}
}
RedisModule_ReplySetArrayLength(ctx, count);
return REDISMODULE_OK;
}
int getkeys_fixed(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
{
int i;
RedisModule_ReplyWithArray(ctx, argc - 1);
for (i = 1; i < argc; i++) {
RedisModule_ReplyWithString(ctx, argv[i]);
}
return REDISMODULE_OK;
}
/* Introspect a command using RM_GetCommandKeys() and returns the list
* of keys. Essentially this is COMMAND GETKEYS implemented in a module.
*/
int getkeys_introspect(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
{
UNUSED(argv);
UNUSED(argc);
if (argc < 3) {
RedisModule_WrongArity(ctx);
return REDISMODULE_OK;
}
size_t cmd_len;
const char *cmd = RedisModule_StringPtrLen(argv[1], &cmd_len);
int num_keys;
int *keyidx = RedisModule_GetCommandKeys(ctx, cmd, &argv[1], argc - 1, &num_keys);
if (!keyidx) {
if (!errno)
RedisModule_ReplyWithEmptyArray(ctx);
else {
char err[100];
switch (errno) {
case ENOENT:
RedisModule_ReplyWithError(ctx, "ERR ENOENT");
break;
case EINVAL:
RedisModule_ReplyWithError(ctx, "ERR EINVAL");
break;
default:
snprintf(err, sizeof(err) - 1, "ERR errno=%d", errno);
RedisModule_ReplyWithError(ctx, err);
break;
}
}
} else {
int i;
RedisModule_ReplyWithArray(ctx, num_keys);
for (i = 0; i < num_keys; i++)
RedisModule_ReplyWithString(ctx, argv[1 + keyidx[i]]);
RedisModule_Free(keyidx);
}
return REDISMODULE_OK;
}
int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
UNUSED(argv);
UNUSED(argc);
if (RedisModule_Init(ctx,"getkeys",1,REDISMODULE_APIVER_1)== REDISMODULE_ERR)
return REDISMODULE_ERR;
if (RedisModule_CreateCommand(ctx,"getkeys.command", getkeys_command,"getkeys-api",0,0,0) == REDISMODULE_ERR)
return REDISMODULE_ERR;
if (RedisModule_CreateCommand(ctx,"getkeys.fixed", getkeys_fixed,"",2,4,1) == REDISMODULE_ERR)
return REDISMODULE_ERR;
if (RedisModule_CreateCommand(ctx,"getkeys.introspect", getkeys_introspect,"",0,0,0) == REDISMODULE_ERR)
return REDISMODULE_ERR;
return REDISMODULE_OK;
}