Data.JsonSpec.Elm.Servant

Generating Elm Clients

servantDefs :: forall {k} (api :: k). Elmable api => Proxy api -> Set Definition

This function will traverse the api type, generating elm definitions for:

• Http requests for each endpoint, including encoders and decoders for anonymous elm types.
• Named Elm types (i.e. Any Specification that is bound to a name using JsonLet
• Decoders and Encoders for named elm types.

You can consume the resulting Definitions using the elm-syntax:Language.Elm.Pretty module.

generateElm

Arguments

:: forall {k} (api :: k). Elmable api

=> OsPath

The directory in which to deposit Elm code.

-> Proxy api

-> IO ()

"Batteries included" way to generate some Elm code on disk in a given a directory. The directory should be dedicated to the generated Elm code and you shouldn't try to store anything else in that directory, Elm files or otherwise.

This function will succeed without error if (and only if) the directory already exists and its contents exactly match what would be generated anyway.

If the files on disk are wrong, then an error is thrown, and the files are unmodified.

If the directory does not exist, then it is created and the Elm code is generated inside the directory, then an error is thrown.

The intent is that you can use this function (thinly wrapped with the appropriate directory and api spec) as the main function for a test suite, where the "test" is that the files on disk are already correct. We throw an error even in the case where we generate files for you because, for instance, you wouldn't want CI to be generating these files when you forgot to check them in in the first place.

Extensions

The symbols in this section are mainly exposed in case you are using some extensions to the standard servant types and need to build some companion extensions to generate proper Elm types for them. For most normal usage you will probably just use generateElm (or possibly servantDefs).

class Elmable (e :: k) where

Class of servant APIs for which Elm client code can be generated.

Methods

endpoints :: [Param] -> Definitions ()

Collect all the Elm definitions needed to implement a client for the API. This is called recursively on our walk down the API tree, and the [Param] argument contains all the request parameters (like Capture, ReqBody', etc) that have been encountered so far on whatever particular branch . It will start out empty at the API root.

Instances

Elmable (ToServantApi api) => Elmable (NamedRoutes api :: Type)

Defined in Data.JsonSpec.Elm.Servant

Methods

endpoints :: [Param] -> Definitions ()

(Elmable a, Elmable b) => Elmable (a :<|> b :: Type)

Defined in Data.JsonSpec.Elm.Servant

Methods

endpoints :: [Param] -> Definitions ()

ReflectMethod method => Elmable (NoContentVerb method :: Type)

Defined in Data.JsonSpec.Elm.Servant

Methods

endpoints :: [Param] -> Definitions ()

(IsParam a, Elmable b) => Elmable (a :> b :: Type)

Defined in Data.JsonSpec.Elm.Servant

Methods

endpoints :: [Param] -> Definitions ()

Elmable (NoContentVerb m) => Elmable (Verb m c t NoContent :: Type)

Defined in Data.JsonSpec.Elm.Servant

Methods

endpoints :: [Param] -> Definitions ()

Elmable (Verb m c t r) => Elmable (Verb m c t (Headers h r) :: Type)

Defined in Data.JsonSpec.Elm.Servant

Methods

endpoints :: [Param] -> Definitions ()

(HasType (EncodingSpec response), ReflectMethod method) => Elmable (Verb method code types response :: Type)

Defined in Data.JsonSpec.Elm.Servant

Methods

endpoints :: [Param] -> Definitions ()

class IsParam (a :: k) where

Obtain a value-level request parameter type from the type-level servant parameter type.

Methods

param :: Definitions Param

Instances

KnownSymbol segment => IsParam (segment :: Symbol)

Defined in Data.JsonSpec.Elm.Servant

Methods

param :: Definitions Param

IsParam (a :: k)

The default instance assumes that the API combinator does not contribute to the parameter list or the "name of the endpoint" in any way. This covers things like Summary and Description, or potentially custom combinators created by the user. In the case of custom combinators, you may need to create an overlapping instance if you wish it to affect the elm function parameters or function name.

Defined in Data.JsonSpec.Elm.Servant

Methods

param :: Definitions Param

KnownSymbol name => IsParam (Capture name tpy :: Type)

Defined in Data.JsonSpec.Elm.Servant

Methods

param :: Definitions Param

KnownSymbol name => IsParam (Header' (Optional ': mods) name a :: Type)

Defined in Data.JsonSpec.Elm.Servant

Methods

param :: Definitions Param

KnownSymbol name => IsParam (Header' (Required ': mods) name a :: Type)

Defined in Data.JsonSpec.Elm.Servant

Methods

param :: Definitions Param

IsParam (Header' mods name a) => IsParam (Header' (other ': mods) name a :: Type)

Defined in Data.JsonSpec.Elm.Servant

Methods

param :: Definitions Param

KnownSymbol name => IsParam (QueryParam' (Optional ': more) name typ :: Type)

Defined in Data.JsonSpec.Elm.Servant

Methods

param :: Definitions Param

KnownSymbol name => IsParam (QueryParam' (Required ': more) name typ :: Type)

Defined in Data.JsonSpec.Elm.Servant

Methods

param :: Definitions Param

IsParam (QueryParam' more name typ) => IsParam (QueryParam' (other ': more) name typ :: Type)

Defined in Data.JsonSpec.Elm.Servant

Methods

param :: Definitions Param

HasType (DecodingSpec a) => IsParam (ReqBody' (Required ': mods) (JSON ': accept) a :: Type)

Defined in Data.JsonSpec.Elm.Servant

Methods

param :: Definitions Param

IsParam (ReqBody' mods '[JSON] a) => IsParam (ReqBody' (other ': mods) (JSON ': accept) a :: Type)

Defined in Data.JsonSpec.Elm.Servant

Methods

param :: Definitions Param

IsParam (ReqBody' mods accept a) => IsParam (ReqBody' mods (other ': accept) a :: Type)

Defined in Data.JsonSpec.Elm.Servant

Methods

param :: Definitions Param

data Param

Constructors

PathParam PathParam

HeaderParam HeaderParam

QueryParam QP

BodyEncoder

Fields

• elmType :: Type Void
• encoder :: Expression Void

Ignore

This is for things like Summary

Instances

Eq Param

Defined in Data.JsonSpec.Elm.Servant

Methods

(==) :: Param -> Param -> Bool

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

data PathParam

Constructors

Static Text

Capture Text

Instances

Eq PathParam

Defined in Data.JsonSpec.Elm.Servant

Methods

(==) :: PathParam -> PathParam -> Bool

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

data HeaderParam

Constructors

RequiredHeader Text

OptionalHeader Text

Instances

Eq HeaderParam

Defined in Data.JsonSpec.Elm.Servant

Methods

(==) :: HeaderParam -> HeaderParam -> Bool

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

data QP

Constructors

RequiredQP Text

OptionalQP Text

Instances

Eq QP

Defined in Data.JsonSpec.Elm.Servant

Methods

(==) :: QP -> QP -> Bool

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