Data.Configurator.Types

Types for working with configuration files.

Documentation

data AutoConfig

Directions for automatically reloading Config data.

Constructors

AutoConfig

Fields

interval :: Int

Interval (in seconds) at which to check for updates to config files. The smallest allowed interval is one second.

onError :: SomeException -> IO ()

Action invoked when an attempt to reload a Config or notify a ChangeHandler causes an exception to be thrown.

If this action rethrows its exception or throws a new exception, the modification checking thread will be killed. You may want your application to treat that as a fatal error, as its configuration may no longer be consistent.

Instances

Show AutoConfig

Typeable AutoConfig

data ConfigCache

Global configuration data. This is the top-level config from which Config values are derived by choosing a root location.

type Name = Text

The name of a Config value.

data Value

A value in a Config.

Constructors

Bool Bool

A Boolean. Represented in a configuration file as on or off, true or false (case sensitive).

String Text

A Unicode string. Represented in a configuration file as text surrounded by double quotes.

Escape sequences:

• \n - newline
• \r - carriage return
• \t - horizontal tab
• \\ - backslash
• \" - quotes
• \uxxxx - Unicode character, encoded as four hexadecimal digits
• \uxxxx\uxxxx - Unicode character (as two UTF-16 surrogates)

Number Scientific

Integer.

List [Value]

Heterogeneous list. Represented in a configuration file as an opening square bracket "[", followed by a comma-separated series of values, ending with a closing square bracket "]".

Instances

Eq Value

Data Value

Show Value

Typeable Value

FromValue Value

FromMaybeValue Value

data Worth a

Constructors

Required

Fields

worth :: a

Optional

Fields

worth :: a

Instances

Functor Worth

Typeable1 Worth

Eq a => Eq (Worth a)

Show a => Show (Worth a)

IsString (Worth FilePath)

Hashable a => Hashable (Worth a)

Exceptions

data ParseError

An error occurred during the low-level parsing of a configuration file.

Constructors

ParseError FilePath String

Instances

Show ParseError

Typeable ParseError

Exception ParseError

data ConfigError

An error (or warning) from a higher-level parser of a configuration file.

Constructors

ConfigError

Fields

configErrorLocation :: ConfigErrorLocation

configConversionError :: Maybe [ConversionError]

Instances

Eq ConfigError

Show ConfigError

Typeable ConfigError

Exception ConfigError

data ConfigErrorLocation

Constructors

KeyMissing [Name]

Key FilePath Name

Instances

Eq ConfigErrorLocation

Show ConfigErrorLocation

Typeable ConfigErrorLocation

data ConversionError

Constructors

ConversionError

Fields

conversionErrorLoc :: Text

conversionErrorWhy :: ConversionErrorWhy

conversionErrorVal :: !(Maybe Value)

conversionErrorType :: !(Maybe TypeRep)

conversionErrorMsg :: !(Maybe Text)

Instances

Eq ConversionError

Show ConversionError

Typeable ConversionError

Exception ConversionError

data ConversionErrorWhy

Constructors

MissingValue

ExtraValues

ExhaustedValues

TypeError

ValueError

MonadFail

OtherError

Instances

Eq ConversionErrorWhy

Show ConversionErrorWhy

Typeable ConversionErrorWhy

defaultConversionError :: ConversionError

data KeyError

An error occurred while lookup up the given Name.

Constructors

KeyError Name

Instances

Show KeyError

Typeable KeyError

Exception KeyError

Notification of configuration changes

data Pattern

A pattern specifying the name of a property that has changed.

This type is an instance of the IsString class. If you use the OverloadedStrings language extension and want to write a prefix-matching pattern as a literal string, do so by suffixing it with ".*", for example as follows:

 "foo.*"

If a pattern written as a literal string does not end with ".*", it is assumed to be exact.

Instances

Eq Pattern

Data Pattern

Show Pattern

Typeable Pattern

IsString Pattern

Hashable Pattern

type ChangeHandler

Arguments

 = Name

Name of the changed property.

-> Maybe Value

Its new value, or Nothing if it has vanished.

-> IO ()

An action to be invoked if a configuration property is changed.

If this action is invoked and throws an exception, the onError function will be called.