Safe HaskellSafe-Infered




JSON utility functions.


JSON-related functions

type JSField = (String, JSValue)Source

type JSRecord = [JSField]Source

A type alias for the list-based representation of J.JSObject.

fromJResult :: Monad m => String -> Result a -> m aSource

Converts a JSON Result into a monadic value.

readEitherString :: Monad m => JSValue -> m StringSource

Tries to read a string from a JSON value.

In case the value was not a string, we fail the read (in the context of the current monad.



:: Monad m 
=> String

Operation description (for error reporting)

-> String

Input message

-> m [JSObject JSValue] 

Converts a JSON message into an array of JSON objects.

fromObj :: (JSON a, Monad m) => JSRecord -> String -> m aSource

Reads the value of a key in a JSON object.

maybeFromObj :: (JSON a, Monad m) => JSRecord -> String -> m (Maybe a)Source

Reads the value of an optional key in a JSON object. Missing keys, or keys that have a 'null' value, will be returned as Nothing, otherwise we attempt deserialisation and return a Just value.

fromObjWithDefault :: (JSON a, Monad m) => JSRecord -> String -> a -> m aSource

Reads the value of a key in a JSON object with a default if missing. Note that both missing keys and keys with value 'null' will case the default value to be returned.



:: (JSON a, Monad m) 
=> String

The key name

-> JSValue

The value to read

-> m a 

Reads a JValue, that originated from an object key.

fromJVal :: (Monad m, JSON a) => JSValue -> m aSource

Small wrapper over readJSON.

jsonHead :: JSON b => [a] -> (a -> b) -> JSValueSource

Helper function that returns Null or first element of the list.

getMaybeJsonHead :: JSON b => [a] -> (a -> Maybe b) -> JSValueSource

Helper for extracting Maybe values from a possibly empty list.

asJSObject :: Monad m => JSValue -> m (JSObject JSValue)Source

Converts a JSON value into a JSON object.

asObjectList :: Monad m => [JSValue] -> m [JSObject JSValue]Source

Coneverts a list of JSON values into a list of JSON objects.



:: JSON a 
=> String

Textual owner in error messages

-> JSRecord

The object array

-> String

The desired key from the object

-> Result a 

Try to extract a key from an object with better error reporting than fromObj.

toArray :: Monad m => JSValue -> m [JSValue]Source

Ensure a given JSValue is actually a JSArray.

optionalJSField :: JSON a => String -> Maybe a -> Maybe JSFieldSource

Creates a Maybe JSField. If the value string is Nothing, the JSField will be Nothing as well.

optFieldsToObj :: [Maybe JSField] -> JSValueSource

Creates an object with all the non-Nothing fields of the given list.

Container type (special type for JSON serialisation)

class HasStringRepr a whereSource

Class of types that can be converted from Strings. This is similar to the Read class, but it's using a different serialisation format, so we have to define a separate class. Mostly useful for custom key types in JSON dictionaries, which have to be backed by strings.


fromStringRepr :: Monad m => String -> m aSource

toStringRepr :: a -> StringSource


HasStringRepr String

Trivial instance HasStringRepr for String.

HasStringRepr DiskTemplate 

newtype GenericContainer a b Source

The container type, a wrapper over Data.Map




fromContainer :: Map a b


Arbitrary OsParams 
Arbitrary ClusterNicParams 
Arbitrary ClusterOsParams 
Arbitrary ClusterBeParams 
Arbitrary OsHvParams

No real arbitrary instance for OsHvParams yet.

Arbitrary ClusterHvParams

No real arbitrary instance for ClusterHvParams yet.

(Eq a, Eq b) => Eq (GenericContainer a b) 
(Show a, Show b) => Show (GenericContainer a b) 
(NFData a, NFData b) => NFData (GenericContainer a b) 
(HasStringRepr a, Ord a, JSON b) => JSON (GenericContainer a b) 

type Container = GenericContainer StringSource

Type alias for string keys.

readContainer :: (Monad m, HasStringRepr a, Ord a, JSON b) => JSObject JSValue -> m (GenericContainer a b)Source

showContainer :: (HasStringRepr a, JSON b) => GenericContainer a b -> JSValueSource