Module: Redis::EM::Mutex::ScriptHandlerMixin::Scripts

Defined in:: lib/redis/em-mutex/script_handler.rb,
lib/redis/em-mutex/script_handler.rb

Constant Summary collapse

TRY_LOCK_MULTI = lock multi *keys, lock_id, msexpire_at > 1 > 0

<<-EOL
  local size=#KEYS
  local lock=ARGV[1]
  local exp=tonumber(ARGV[2])
  local args={}
  for i=1,size do
    args[#args+1]=KEYS[i]
    args[#args+1]=lock
  end
  if 1==redis.call('msetnx',unpack(args)) then
    for i=1,size do
      redis.call('pexpireat',KEYS[i],exp)
    end
    return 1
  end
  return 0
EOL

LOCK_MULTI = lock multi *keys, lock_id, msexpire_at > OK > DD (deadlock) > milliseconds ttl wait

<<-EOL
  local size=#KEYS
  local lock=ARGV[1]
  local exp=tonumber(ARGV[2])
  local args={}
  for i=1,size do
    args[#args+1]=KEYS[i]
    args[#args+1]=lock
  end
  if 1==redis.call('msetnx',unpack(args)) then
    for i=1,size do
      redis.call('pexpireat',KEYS[i],exp)
    end
    return 'OK'
  end
  local res=redis.call('mget',unpack(KEYS))
  exp=nil
  for i, v in next, res do
    if v==lock then
      return 'DD'
    elseif v then
      v=redis.call('pttl',KEYS[i])
      if not exp or v<exp then
        exp=v
      end
    end
  end
  return exp or -1
EOL

UNLOCK_MULTI = unlock multiple *keys, lock_id, pub_channel, pub_message > #keys unlocked

<<-EOL
  local size=#KEYS
  local lock=ARGV[1]
  local args={}
  local res=redis.call('mget',unpack(KEYS))
  for i=1,size do
    if res[i]==lock then
      args[#args+1]=KEYS[i]
    end
  end
  if #args>0 then
    if redis.call('del',unpack(args)) > 0 then
      redis.call('publish',ARGV[2],ARGV[3])
    end
  end
  return #args
EOL

REFRESH_MULTI = refresh multi *keys, lock_id, msexpire_at > 1 > 0

<<-EOL
  local size=#KEYS
  local lock=ARGV[1]
  local exp=tonumber(ARGV[2])
  local args={}
  local res=redis.call('mget',unpack(KEYS))
  for i=1,size do
    if res[i]==lock then
      args[#args+1]=KEYS[i]
    end
  end
  if #args==size then
    for i=1,size do
      if 0==redis.call('pexpireat',args[i],exp) then
        redis.call('del',unpack(args))
        return 0
      end
    end
    return 1
  elseif #args>0 then
    redis.call('del',unpack(args))
  end
  return 0
EOL

IS_LOCKED_MULTI = locked? multi *keys > 1 > 0

<<-EOL
  for i=1,#KEYS do
    if 1==redis.call('exists',KEYS[i]) then
      return 1
    end
  end
  return 0
EOL

TRY_LOCK_SINGLE = try_lock single key, lock_id, msexpire_at > 1 > 0

<<-EOL
  local key=KEYS[1]
  local lock=ARGV[1]
  if 1==redis.call('setnx',key,lock) then
    return redis.call('pexpireat',key,tonumber(ARGV[2]))
  end
  return 0
EOL

LOCK_SINGLE = lock single key, lock_id, msexpire_at > OK > DD (deadlock) > milliseconds ttl wait

<<-EOL
  local key=KEYS[1]
  local lock=ARGV[1]
  if 1==redis.call('setnx',key,lock) then
    redis.call('pexpireat',key,tonumber(ARGV[2]))
    return 'OK'
  end
  if lock==redis.call('get',key) then
    return 'DD'
  end
  return redis.call('pttl',key)
EOL

UNLOCK_SINGLE = unlock single key, lock_id, pub_channel, pub_message > 1 > 0

<<-EOL
  local key=KEYS[1]
  local res=redis.call('get',key)
  if res==ARGV[1] then
    if 1==redis.call('del',key) then
      redis.call('publish',ARGV[2],ARGV[3])
      return 1
    end
  end
  return 0
EOL

REFRESH_SINGLE = refresh single key, lock_id, msexpire_at > 1 > 0

<<-EOL
  local key=KEYS[1]
  local res=redis.call('get',key)
  if res==ARGV[1] then
    return redis.call('pexpireat',key,tonumber(ARGV[2]))
  end
  return 0
EOL

MULTI =

{
  TRY_LOCK_MULTI_SHA1 => TRY_LOCK_MULTI,
  LOCK_MULTI_SHA1 => LOCK_MULTI,
  UNLOCK_MULTI_SHA1 => UNLOCK_MULTI,
  REFRESH_MULTI_SHA1 => REFRESH_MULTI,
  IS_LOCKED_MULTI_SHA1 => IS_LOCKED_MULTI
}

SINGLE =

{
  TRY_LOCK_SINGLE_SHA1 => TRY_LOCK_SINGLE,
  LOCK_SINGLE_SHA1 => LOCK_SINGLE,
  UNLOCK_SINGLE_SHA1 => UNLOCK_SINGLE,
  REFRESH_SINGLE_SHA1 => REFRESH_SINGLE,
}