Servant.API.QueryParam

servant-0.20.2: A family of combinators for defining webservices APIs

Safe Haskell | None
Language | Haskell2010

Servant.API.QueryParam

Synopsis

- data QueryFlag (sym :: Symbol)
- type QueryParam = QueryParam' '[Optional, Strict]
- data QueryParam' (mods :: [Type]) (sym :: Symbol) a
- data QueryParams (sym :: Symbol) a

# Documentation

data QueryFlag (sym :: Symbol) #

Lookup a potentially value-less query string parameter with boolean semantics. If the param `sym` is there without any value, or if it's there with value "true" or "1", it's interpreted as `True`. Otherwise, it's interpreted as `False`.

Example:

    >>> -- /books?published
    >>> type MyApi = "books" :> QueryFlag "published" :> Get '[JSON] [Book]

#### Instances

Instances details

(KnownSymbol sym, HasLink sub) => HasLink (QueryFlag sym :> sub :: Type) # |
Instance details Defined in Servant.Links Methods toLink :: (Link -> a) -> Proxy (QueryFlag sym :> sub) -> Link -> MkLink (QueryFlag sym :> sub) a #
type MkLink (QueryFlag sym :> sub :: Type) a # |
Instance details Defined in Servant.Links type MkLink (QueryFlag sym :> sub :: Type) a = Bool -> MkLink sub a

type QueryParam = QueryParam' '[Optional, Strict] #

Lookup the value associated to the `sym` query string parameter and try to extract it as a value of type `a`.

Example:

    >>> -- /books?author=<author name>
    >>> type MyApi = "books" :> QueryParam "author" Text :> Get '[JSON] [Book]

data QueryParam' (mods :: [Type]) (sym :: Symbol) a #

`QueryParam` which can be `Required`, `Lenient`, or modified otherwise.

#### Instances

Instances details

(KnownSymbol sym, ToHttpApiData v, HasLink sub, SBoolI (FoldRequired mods)) => HasLink (QueryParam' mods sym v :> sub :: Type) # |
Instance details Defined in Servant.Links Methods toLink :: (Link -> a) -> Proxy (QueryParam' mods sym v :> sub) -> Link -> MkLink (QueryParam' mods sym v :> sub) a #
type MkLink (QueryParam' mods sym v :> sub :: Type) a # |
Instance details Defined in Servant.Links type MkLink (QueryParam' mods sym v :> sub :: Type) a = If (FoldRequired mods) v (Maybe v) -> MkLink sub a

data QueryParams (sym :: Symbol) a #

Lookup the values associated to the `sym` query string parameter and try to extract it as a value of type `[a]`. This is typically meant to support query string parameters of the form `param[]=val1&param[]=val2` and so on. Note that servant doesn't actually require the `[]`s and will fetch the values just fine with `param=val1&param=val2`, too.

Example:

    >>> -- /books?authors[]=<author1>&authors[]=<author2>&...
    >>> type MyApi = "books" :> QueryParams "authors" Text :> Get '[JSON] [Book]

#### Instances

Instances details

(KnownSymbol sym, ToHttpApiData v, HasLink sub) => HasLink (QueryParams sym v :> sub :: Type) # |
Instance details Defined in Servant.Links Methods toLink :: (Link -> a) -> Proxy (QueryParams sym v :> sub) -> Link -> MkLink (QueryParams sym v :> sub) a #
type MkLink (QueryParams sym v :> sub :: Type) a # |
Instance details Defined in Servant.Links type MkLink (QueryParams sym v :> sub :: Type) a = [v] -> MkLink sub a