// Cmd performs the given command on the correct cluster node and gives back the
// command's reply. The command *must* have a key parameter (i.e. len(args) >=
// 1). If any MOVED or ASK errors are returned they will be transparently
// handled by this method.
func (c *Cluster) Cmd(cmd string, args ...interface{}) *redis.Resp {
if len(args) < 1 {
return errorResp(ErrBadCmdNoKey)
}
key, err := redis.KeyFromArgs(args)
if err != nil {
return errorResp(err)
}
client, err := c.getConn(key, "")
if err != nil {
return errorResp(err)
}
return c.clientCmd(client, cmd, args, false, nil, false)
}
// LuaEval calls EVAL on the given Cmder for the given script, passing the key
// count and argument list in as well. See http://redis.io/commands/eval for
// more on how EVAL works and for the meaning of the keys argument.
//
// LuaEval will automatically try to call EVALSHA first in order to preserve
// bandwidth, and only falls back on EVAL if the script has never been used
// before.
//
// This method works with any of the Cmder's implemented in radix.v2, including
// Client, Pool, and Cluster.
//
// r := util.LuaEval(c, `return redis.call('GET', KEYS[1])`, 1, "foo")
//
func LuaEval(c Cmder, script string, keys int, args ...interface{}) *redis.Resp {
mainKey, _ := redis.KeyFromArgs(args...)
sumRaw := sha1.Sum([]byte(script))
sum := hex.EncodeToString(sumRaw[:])
var r *redis.Resp
if err := withClientForKey(c, mainKey, func(cc Cmder) {
r = c.Cmd("EVALSHA", sum, keys, args)
if r.Err != nil && strings.HasPrefix(r.Err.Error(), "NOSCRIPT") {
r = c.Cmd("EVAL", script, keys, args)
}
}); err != nil {
return redis.NewResp(err)
}
return r
}