Data.Snowchecked

This generates unique (guaranteed) identifiers build from a timestamp, counter, and node id. Identifiers are convertible to values which are monotonically increasing with respect to time.

Documentation

newSnowcheckedGen :: MonadIO io => SnowcheckedConfig -> Word256 -> io SnowcheckedGen

Create a new generator. Takes a configuration and node id.

nextFlake :: MonadIO io => SnowcheckedGen -> io Flake

Generates the next id.

data SnowcheckedConfig

Configuration that specifies how much bits are used for each part of the id. These values are not validated and may be any legal value for the type.

The default value provided by def is 64 bits in total length, just like the original Snowflake algorithm. However, 4 bits are taken from the count bits and used for check bits. Note that specifying 0 check bits results in the normal snowflake generation.

Constructors

SnowcheckedConfig

Fields

• confTimeBits :: Word8

  Number of bits used to hold the time

• confCountBits :: Word8

  Number of bits used to count instances per-time

• confNodeBits :: Word8

  Number of bits derived from the node id

• confCheckBits :: Word8

  Number of bits used to store the checksum

Instances

Eq SnowcheckedConfig

Defined in Data.Snowchecked.Types

Methods

(==) :: SnowcheckedConfig -> SnowcheckedConfig -> Bool

(/=) :: SnowcheckedConfig -> SnowcheckedConfig -> Bool

Show SnowcheckedConfig

Defined in Data.Snowchecked.Types

Methods

showsPrec :: Int -> SnowcheckedConfig -> ShowS

show :: SnowcheckedConfig -> String

showList :: [SnowcheckedConfig] -> ShowS

Generic SnowcheckedConfig

Defined in Data.Snowchecked.Types

Associated Types

type Rep SnowcheckedConfig :: Type -> Type

Methods

from :: SnowcheckedConfig -> Rep SnowcheckedConfig x

to :: Rep SnowcheckedConfig x -> SnowcheckedConfig

Default SnowcheckedConfig

Defined in Data.Snowchecked.Types

Methods

def :: SnowcheckedConfig

NFData SnowcheckedConfig

Defined in Data.Snowchecked.Types

Methods

rnf :: SnowcheckedConfig -> ()

type Rep SnowcheckedConfig

Defined in Data.Snowchecked.Types

type Rep SnowcheckedConfig = D1 ('MetaData "SnowcheckedConfig" "Data.Snowchecked.Types" "snowchecked-0.0.0.1-1XcYrHn4yNqBegYObj5FEb" 'False) (C1 ('MetaCons "SnowcheckedConfig" 'PrefixI 'True) ((S1 ('MetaSel ('Just "confTimeBits") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Word8) :*: S1 ('MetaSel ('Just "confCountBits") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Word8)) :*: (S1 ('MetaSel ('Just "confNodeBits") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Word8) :*: S1 ('MetaSel ('Just "confCheckBits") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Word8))))

data SnowcheckedGen

The state that needs to be communicated between flake generation calls. - This should not be accessed or created directly by consumers of this library: - doing so may cause your code to hang indefinitely.

data Flake

The state of a given generated instance. Note that the actual value is calculated on demand.

Instances

Eq Flake

Defined in Data.Snowchecked.Types

Methods

(==) :: Flake -> Flake -> Bool

(/=) :: Flake -> Flake -> Bool

Show Flake

Defined in Data.Snowchecked.Types

Methods

showsPrec :: Int -> Flake -> ShowS

show :: Flake -> String

showList :: [Flake] -> ShowS

Generic Flake

Defined in Data.Snowchecked.Types

Associated Types

type Rep Flake :: Type -> Type

Methods

from :: Flake -> Rep Flake x

to :: Rep Flake x -> Flake

NFData Flake

Defined in Data.Snowchecked.Types

Methods

rnf :: Flake -> ()

type Rep Flake

Defined in Data.Snowchecked.Types

type Rep Flake = D1 ('MetaData "Flake" "Data.Snowchecked.Types" "snowchecked-0.0.0.1-1XcYrHn4yNqBegYObj5FEb" 'False) (C1 ('MetaCons "Flake" 'PrefixI 'True) ((S1 ('MetaSel ('Just "flakeTime") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Word256) :*: S1 ('MetaSel ('Just "flakeCount") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Word256)) :*: (S1 ('MetaSel ('Just "flakeNodeId") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Word256) :*: S1 ('MetaSel ('Just "flakeConfig") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 SnowcheckedConfig))))

snowcheckedConfigBitCount :: SnowcheckedConfig -> Word32

uniqueFlakeCount :: SnowcheckedConfig -> Integer

Provides the count of total number of unique flakes possibly generated by this configuration.