Conferer.FromConfig.Internal

Internal module providing FromConfig functionality

Documentation

class FromConfig a where

The typeclass for defining the way to get values from a Config, hiding the Text based nature of the Sources and parse whatever value as the types sees fit

Some of these instances are provided in different packages to avoid the heavy dependencies.

It provides a reasonable default using Generics so most of the time user need not to implement this typeclass.

Minimal complete definition

Nothing

Methods

fromConfig :: Key -> Config -> IO a

This function uses a Config and a scoping Key to get a value.

Some conventions:

• When some Key is missing this function should throw MissingRequiredKey
• For any t it should hold that fetchFromConfig k (config & addDefault k t) == t meaning that a default on the same key with the right type should be used as a default and with no configuration that value should be returned
• Try desconstructing the value in as many keys as possible since is allows easier partial overriding.

default fromConfig :: (Typeable a, Generic a, IntoDefaultsG (Rep a), FromConfigG (Rep a)) => Key -> Config -> IO a

Instances

FromConfig Bool

Defined in Conferer.FromConfig.Internal

Methods

fromConfig :: Key -> Config -> IO Bool

FromConfig Float

Defined in Conferer.FromConfig.Internal

Methods

fromConfig :: Key -> Config -> IO Float

FromConfig Int

Defined in Conferer.FromConfig.Internal

Methods

fromConfig :: Key -> Config -> IO Int

FromConfig Integer

Defined in Conferer.FromConfig.Internal

Methods

fromConfig :: Key -> Config -> IO Integer

FromConfig ()

Defined in Conferer.FromConfig.Internal

Methods

fromConfig :: Key -> Config -> IO ()

Typeable a => FromConfig a

Defined in Conferer.FromConfig.Internal

Methods

fromConfig :: Key -> Config -> IO a

FromConfig String

Defined in Conferer.FromConfig.Internal

Methods

fromConfig :: Key -> Config -> IO String

FromConfig ByteString

Defined in Conferer.FromConfig.Internal

Methods

fromConfig :: Key -> Config -> IO ByteString

FromConfig ByteString

Defined in Conferer.FromConfig.Internal

Methods

fromConfig :: Key -> Config -> IO ByteString

FromConfig Text

Defined in Conferer.FromConfig.Internal

Methods

fromConfig :: Key -> Config -> IO Text

FromConfig File

Defined in Conferer.FromConfig.Internal

Methods

fromConfig :: Key -> Config -> IO File

(Typeable a, FromConfig a) => FromConfig [a]

Defined in Conferer.FromConfig.Internal

Methods

fromConfig :: Key -> Config -> IO [a]

(Typeable a, FromConfig a) => FromConfig (Maybe a)

Defined in Conferer.FromConfig.Internal

Methods

fromConfig :: Key -> Config -> IO (Maybe a)

fetchFromConfig :: forall a. (FromConfig a, Typeable a) => Key -> Config -> IO a

class DefaultConfig a where

Utility only typeclass to smooth the naming differences between default values for external library settings

This typeclass is not used internally it's only here for convinience for users

Methods

configDef :: a

newtype File

A newtype wrapper for a FilePath to allow implementing FromConfig with something better than just a String

Constructors

File FilePath

Instances

Eq File

Defined in Conferer.FromConfig.Internal

Methods

(==) :: File -> File -> Bool

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

Ord File

Defined in Conferer.FromConfig.Internal

Methods

compare :: File -> File -> Ordering

(<) :: File -> File -> Bool

(<=) :: File -> File -> Bool

(>) :: File -> File -> Bool

(>=) :: File -> File -> Bool

max :: File -> File -> File

min :: File -> File -> File

Read File

Defined in Conferer.FromConfig.Internal

Methods

readsPrec :: Int -> ReadS File

readList :: ReadS [File]

readPrec :: ReadPrec File

readListPrec :: ReadPrec [File]

Show File

Defined in Conferer.FromConfig.Internal

Methods

showsPrec :: Int -> File -> ShowS

show :: File -> String

showList :: [File] -> ShowS

IsString File

Defined in Conferer.FromConfig.Internal

Methods

fromString :: String -> File

FromConfig File

Defined in Conferer.FromConfig.Internal

Methods

fromConfig :: Key -> Config -> IO File

unFile :: File -> FilePath

parseBool :: Text -> Maybe Bool

Helper function to parse a Bool from Text

data OverrideFromConfig a

Constructors

OverrideFromConfig (Key -> Config -> IO a)

fetchFromConfigByRead :: (Typeable a, Read a) => Key -> Config -> IO a

Allow the programmer to override this FromConfig instance by providing a special OverrideFromConfig value.

To avoid infinite recursion we remove the Override before calling the value

Helper function to implement fetchFromConfig using the Read instance

fetchFromConfigByIsString :: (Typeable a, IsString a) => Key -> Config -> IO a

Helper function to implement fetchFromConfig using the IsString instance

fetchFromConfigWith :: forall a. Typeable a => (Text -> Maybe a) -> Key -> Config -> IO a

Helper function to implement fetchFromConfig using some parsing function

fromDynamics :: forall a. Typeable a => [Dynamic] -> Maybe a

addDefaultsAfterDeconstructingToDefaults

Arguments

:: forall a. Typeable a

=> (a -> [(Key, Dynamic)])

Function to deconstruct the value

-> Key

Key where to look for the value

-> Config

The config

-> IO Config

Helper function does the plumbing of desconstructing a default into smaller defaults, which is usefull for nested fetchFromConfig.

overrideFetch :: forall a. Typeable a => (Key -> Config -> IO a) -> Dynamic

Helper function to override the fetching function for a certain key.

This function creates a Dynamic that when added to the defaults allows overriding the default FromConfig instance.

data ConfigParsingError

Exception to show that a value couldn't be parsed properly

Constructors

ConfigParsingError Key Text TypeRep

Instances

Eq ConfigParsingError

Defined in Conferer.FromConfig.Internal

Methods

(==) :: ConfigParsingError -> ConfigParsingError -> Bool

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

Show ConfigParsingError

Defined in Conferer.FromConfig.Internal

Methods

showsPrec :: Int -> ConfigParsingError -> ShowS

show :: ConfigParsingError -> String

showList :: [ConfigParsingError] -> ShowS

Exception ConfigParsingError

Defined in Conferer.FromConfig.Internal

Methods

toException :: ConfigParsingError -> SomeException

fromException :: SomeException -> Maybe ConfigParsingError

displayException :: ConfigParsingError -> String

throwConfigParsingError :: forall a b. Typeable a => Key -> Text -> IO b

Helper function to throw ConfigParsingError

configParsingError :: forall a. Typeable a => Key -> Text -> ConfigParsingError

Helper function to create a ConfigParsingError

data MissingRequiredKey

Exception to show that some non optional Key was missing while trying to fetchFromConfig

Constructors

MissingRequiredKey [Key] TypeRep

Instances

Eq MissingRequiredKey

Defined in Conferer.FromConfig.Internal

Methods

(==) :: MissingRequiredKey -> MissingRequiredKey -> Bool

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

Show MissingRequiredKey

Defined in Conferer.FromConfig.Internal

Methods

showsPrec :: Int -> MissingRequiredKey -> ShowS

show :: MissingRequiredKey -> String

showList :: [MissingRequiredKey] -> ShowS

Exception MissingRequiredKey

Defined in Conferer.FromConfig.Internal

Methods

toException :: MissingRequiredKey -> SomeException

fromException :: SomeException -> Maybe MissingRequiredKey

displayException :: MissingRequiredKey -> String

throwMissingRequiredKey :: forall t a. Typeable t => Key -> IO a

Simplified helper function to throw a MissingRequiredKey

missingRequiredKey :: forall t. Typeable t => Key -> MissingRequiredKey

Simplified helper function to create a MissingRequiredKey

throwMissingRequiredKeys :: forall t a. Typeable t => [Key] -> IO a

Helper function to throw a MissingRequiredKey

missingRequiredKeys :: forall a. Typeable a => [Key] -> MissingRequiredKey

Helper function to create a MissingRequiredKey

fetchRequiredFromDefaults :: forall a. Typeable a => Key -> Config -> IO a

Fetch from value from the defaults map of a Config or else throw

fetchFromDefaults :: forall a. Typeable a => Key -> Config -> Maybe a

Fetch from value from the defaults map of a Config or else return a Nothing

fetchFromRootConfig :: forall a. (FromConfig a, Typeable a) => Config -> IO a

Same as fetchFromConfig using the root key

fetchFromConfigWithDefault :: forall a. (Typeable a, FromConfig a) => Config -> Key -> a -> IO a

Same as fetchFromConfig but adding a user defined default before fetchFromConfiging so it doesn't throw a MissingKeyError

fetchFromRootConfigWithDefault :: forall a. (Typeable a, FromConfig a) => Config -> a -> IO a

Same as fetchFromConfigWithDefault using the root key

class FromConfigG f where

Purely Generics machinery, ignore...

Methods

fromConfigG :: Key -> Config -> IO (f a)

Instances

(FromConfig inner, Typeable inner) => FromConfigG (Rec0 inner)

Defined in Conferer.FromConfig.Internal

Methods

fromConfigG :: Key -> Config -> IO (Rec0 inner a)

FromConfigG inner => FromConfigG (D1 metadata inner)

Defined in Conferer.FromConfig.Internal

Methods

fromConfigG :: Key -> Config -> IO (D1 metadata inner a)

(FromConfigWithConNameG inner, Constructor constructor) => FromConfigG (C1 constructor inner)

Defined in Conferer.FromConfig.Internal

Methods

fromConfigG :: Key -> Config -> IO (C1 constructor inner a)

class FromConfigWithConNameG f where

Purely Generics machinery, ignore...

Methods

fromConfigWithConNameG :: String -> Key -> Config -> IO (f a)

Instances

(FromConfigWithConNameG left, FromConfigWithConNameG right) => FromConfigWithConNameG (left :*: right)

Defined in Conferer.FromConfig.Internal

Methods

fromConfigWithConNameG :: String -> Key -> Config -> IO ((left :*: right) a)

(FromConfigG inner, Selector selector) => FromConfigWithConNameG (S1 selector inner)

Defined in Conferer.FromConfig.Internal

Methods

fromConfigWithConNameG :: String -> Key -> Config -> IO (S1 selector inner a)

class IntoDefaultsG f where

Purely Generics machinery, ignore...

Methods

intoDefaultsG :: Key -> f a -> [(Key, Dynamic)]

Instances

Typeable inner => IntoDefaultsG (Rec0 inner)

Defined in Conferer.FromConfig.Internal

Methods

intoDefaultsG :: Key -> Rec0 inner a -> [(Key, Dynamic)]

IntoDefaultsG inner => IntoDefaultsG (D1 metadata inner)

Defined in Conferer.FromConfig.Internal

Methods

intoDefaultsG :: Key -> D1 metadata inner a -> [(Key, Dynamic)]

(IntoDefaultsWithConNameG inner, Constructor constructor) => IntoDefaultsG (C1 constructor inner)

Defined in Conferer.FromConfig.Internal

Methods

intoDefaultsG :: Key -> C1 constructor inner a -> [(Key, Dynamic)]

class IntoDefaultsWithConNameG f where

Purely Generics machinery, ignore...

Methods

intoDefaultsWithConNameG :: String -> Key -> f a -> [(Key, Dynamic)]

Instances

(IntoDefaultsWithConNameG left, IntoDefaultsWithConNameG right) => IntoDefaultsWithConNameG (left :*: right)

Defined in Conferer.FromConfig.Internal

Methods

intoDefaultsWithConNameG :: String -> Key -> (left :*: right) a -> [(Key, Dynamic)]

(IntoDefaultsG inner, Selector selector) => IntoDefaultsWithConNameG (S1 selector inner)

Defined in Conferer.FromConfig.Internal

Methods

intoDefaultsWithConNameG :: String -> Key -> S1 selector inner a -> [(Key, Dynamic)]