PHP Predis: Как преобразовать `redis-cli скрипт загрузки $ LUA_SCRIPT` в методы Predis?

Question

Как конвертировать redis-cli script load $LUA_SCRIPT в методы Predis?

Follow является Lua скрипт:

local lock_key = 'icicle-generator-lock' 
local sequence_key = 'icicle-generator-sequence' 
local logical_shard_id_key = 'icicle-generator-logical-shard-id' 

local max_sequence = tonumber(KEYS[1]) 
local min_logical_shard_id = tonumber(KEYS[2]) 
local max_logical_shard_id = tonumber(KEYS[3]) 
local num_ids = tonumber(KEYS[4]) 

if redis.call('EXISTS', lock_key) == 1 then 
    redis.log(redis.LOG_INFO, 'Icicle: Cannot generate ID, waiting for lock to expire.') 
    return redis.error_reply('Icicle: Cannot generate ID, waiting for lock to expire.') 
end 

--[[ 
Increment by a set number, this can 
--]] 
local end_sequence = redis.call('INCRBY', sequence_key, num_ids) 
local start_sequence = end_sequence - num_ids + 1 
local logical_shard_id = tonumber(redis.call('GET', logical_shard_id_key)) or -1 

if end_sequence >= max_sequence then 
    --[[ 
    As the sequence is about to roll around, we can't generate another ID until we're sure we're not in the same 
    millisecond since we last rolled. This is because we may have already generated an ID with the same time and 
    sequence, and we cannot allow even the smallest possibility of duplicates. It's also because if we roll the sequence 
    around, we will start generating IDs with smaller values than the ones previously in this millisecond - that would 
    break our k-ordering guarantees! 
    The only way we can handle this is to block for a millisecond, as we can't store the time due the purity constraints 
    of Redis Lua scripts. 
    In addition to a neat side-effect of handling leap seconds (where milliseconds will last a little bit longer to bring 
    time back to where it should be) because Redis uses system time internally to expire keys, this prevents any duplicate 
    IDs from being generated if the rate of generation is greater than the maximum sequence per millisecond. 
    Note that it only blocks even it rolled around *not* in the same millisecond; this is because unless we do this, the 
    IDs won't remain ordered. 
    --]] 
    redis.log(redis.LOG_INFO, 'Icicle: Rolling sequence back to the start, locking for 1ms.') 
    redis.call('SET', sequence_key, '-1') 
    redis.call('PSETEX', lock_key, 1, 'lock') 
    end_sequence = max_sequence 
end 

--[[ 
The TIME command MUST be called after anything that mutates state, or the Redis server will error the script out. 
This is to ensure the script is "pure" in the sense that randomness or time based input will not change the 
outcome of the writes. 
See the "Scripts as pure functions" section at http://redis.io/commands/eval for more information. 
--]] 
local time = redis.call('TIME') 

return { 
    start_sequence, 
    end_sequence, -- Doesn't need conversion, the result of INCR or the variable set is always a number. 
    logical_shard_id, 
    tonumber(time[1]), 
    tonumber(time[2]) 
} 



redis-cli script load $LUA_SCRIPT 

Я попытался

$predis->eval(file_get_contents($luaPath), 0); 

или

class ListPushRandomValue extends \Predis\Command\ScriptCommand { 
    public function getKeysCount() { 
     return 0; 
    } 

    public function getScript() { 
     $luaPath = Aa::$vendorRoot .'/icicle/id-generation.lua'; 
     return file_get_contents($luaPath); 
    } 
} 
$predis->getProfile()->defineCommand('t', '\Controller\ListPushRandomValue'); 

$response = $predis->t(); 

Но оба выше показал ошибку ниже.

ERR Error running script (call to f_5849d008682280eed4ec67b97ba50ae546fc5e8d): @user_script:19: user_script:19: attempt to perform arithmetic on local 'end_sequence' (a table value) 

Answer 1

Во-первых, позвольте мне сказать, что я не являюсь экспертом по LUA, но я только что занимался Redis и LUA скрипт для выполнения простой блокировки и заметил несколько ошибок в вопросе.

Процесс преобразования между Redis и LUA должен быть пересмотрен: Conversion. Я думаю, что это поможет с данной ошибкой.

На этом призыве:

$predis->eval(file_get_contents($luaPath), 0); 

Вы передаете содержимое ключей сценария и доступа, но не проходит ни ключи для оценки. Этот звонок верен:

$predis->eval(file_get_contents($luaPath), 4, oneKey, twoKey, threeKey, fourKey); 

Возможно, это и есть причина вышеуказанной ошибки. Надеюсь, это поможет кому-то в будущем.