Safe Haskell | Safe-Inferred |
---|---|
Language | Haskell2010 |
Convert Haskell values to and from HTTP API data such as URL pieces, headers and query parameters.
Synopsis
- class ToHttpApiData a where
- toUrlPiece :: a -> Text
- toEncodedUrlPiece :: a -> Builder
- toHeader :: a -> ByteString
- toQueryParam :: a -> Text
- toEncodedQueryParam :: a -> Builder
- class FromHttpApiData a where
- parseUrlPiece :: Text -> Either Text a
- parseHeader :: ByteString -> Either Text a
- parseQueryParam :: Text -> Either Text a
- parseUrlPieceMaybe :: FromHttpApiData a => Text -> Maybe a
- parseHeaderMaybe :: FromHttpApiData a => ByteString -> Maybe a
- parseQueryParamMaybe :: FromHttpApiData a => Text -> Maybe a
- parseUrlPieceWithPrefix :: FromHttpApiData a => Text -> Text -> Either Text a
- parseHeaderWithPrefix :: FromHttpApiData a => ByteString -> ByteString -> Either Text a
- parseQueryParamWithPrefix :: FromHttpApiData a => Text -> Text -> Either Text a
- toUrlPieces :: (Functor t, ToHttpApiData a) => t a -> t Text
- parseUrlPieces :: (Traversable t, FromHttpApiData a) => t Text -> Either Text (t a)
- toQueryParams :: (Functor t, ToHttpApiData a) => t a -> t Text
- parseQueryParams :: (Traversable t, FromHttpApiData a) => t Text -> Either Text (t a)
- parseBoundedUrlPiece :: (ToHttpApiData a, Bounded a, Enum a) => Text -> Either Text a
- parseBoundedQueryParam :: (ToHttpApiData a, Bounded a, Enum a) => Text -> Either Text a
- parseBoundedHeader :: (ToHttpApiData a, Bounded a, Enum a) => ByteString -> Either Text a
- parseBoundedEnumOf :: (Bounded a, Enum a) => (a -> Text) -> Text -> Either Text a
- parseBoundedEnumOfI :: (Bounded a, Enum a) => (a -> Text) -> Text -> Either Text a
- parseBoundedTextData :: (Show a, Bounded a, Enum a) => Text -> Either Text a
- newtype LenientData a = LenientData {
- getLenientData :: Either Text a
- showTextData :: Show a => a -> Text
- readTextData :: Read a => Text -> Either Text a
Examples
Booleans:
>>>
toUrlPiece True
"true">>>
parseUrlPiece "false" :: Either Text Bool
Right False>>>
parseUrlPieces ["true", "false", "undefined"] :: Either Text [Bool]
Left "could not parse: `undefined'"
Numbers:
>>>
toQueryParam 45.2
"45.2">>>
parseQueryParam "452" :: Either Text Int
Right 452>>>
toQueryParams [1..5] :: [Text]
["1","2","3","4","5"]>>>
parseQueryParams ["127", "255"] :: Either Text [Int8]
Left "out of bounds: `255' (should be between -128 and 127)"
Strings:
>>>
toHeader "hello"
"hello">>>
parseHeader "world" :: Either Text String
Right "world"
Calendar day:
>>>
toQueryParam (fromGregorian 2015 10 03)
"2015-10-03">>>
toGregorian <$> parseQueryParam "2016-12-01"
Right (2016,12,1)
Classes
class ToHttpApiData a where Source #
Convert value to HTTP API data.
WARNING: Do not derive this using DeriveAnyClass
as the generated
instance will loop indefinitely.
toUrlPiece :: a -> Text Source #
Convert to URL path piece.
toEncodedUrlPiece :: a -> Builder Source #
Convert to a URL path piece, making sure to encode any special chars.
The default definition uses
but this may be overriden with a more efficient version.urlEncodeBuilder
False
toHeader :: a -> ByteString Source #
Convert to HTTP header value.
toQueryParam :: a -> Text Source #
Convert to query param value.
toEncodedQueryParam :: a -> Builder Source #
Convert to URL query param,
The default definition uses
but this may be overriden with a more efficient version.urlEncodeBuilder
True
Since: 0.5.1
Instances
class FromHttpApiData a where Source #
Parse value from HTTP API data.
WARNING: Do not derive this using DeriveAnyClass
as the generated
instance will loop indefinitely.
parseUrlPiece :: Text -> Either Text a Source #
Parse URL path piece.
parseHeader :: ByteString -> Either Text a Source #
Parse HTTP header value.
parseQueryParam :: Text -> Either Text a Source #
Parse query param value.
Instances
Maybe
parsers
Maybe
parseUrlPieceMaybe :: FromHttpApiData a => Text -> Maybe a Source #
Parse URL path piece in a
.Maybe
>>>
parseUrlPieceMaybe "12" :: Maybe Int
Just 12
parseHeaderMaybe :: FromHttpApiData a => ByteString -> Maybe a Source #
Parse HTTP header value in a
.Maybe
>>>
parseHeaderMaybe "hello" :: Maybe Text
Just "hello"
parseQueryParamMaybe :: FromHttpApiData a => Text -> Maybe a Source #
Parse query param value in a
.Maybe
>>>
parseQueryParamMaybe "true" :: Maybe Bool
Just True
Prefix parsers
parseUrlPieceWithPrefix :: FromHttpApiData a => Text -> Text -> Either Text a Source #
Case insensitive.
Parse given text case insensitive and then parse the rest of the input
using
.parseUrlPiece
>>>
parseUrlPieceWithPrefix "Just " "just 10" :: Either Text Int
Right 10>>>
parseUrlPieceWithPrefix "Left " "left" :: Either Text Bool
Left "could not parse: `left'"
This can be used to implement
for single field constructors:FromHttpApiData
>>>
data Foo = Foo Int deriving (Show)
>>>
instance FromHttpApiData Foo where parseUrlPiece s = Foo <$> parseUrlPieceWithPrefix "Foo " s
>>>
parseUrlPiece "foo 1" :: Either Text Foo
Right (Foo 1)
parseHeaderWithPrefix :: FromHttpApiData a => ByteString -> ByteString -> Either Text a Source #
Parse given bytestring then parse the rest of the input using
.parseHeader
data BasicAuthToken = BasicAuthToken Text deriving (Show) instance FromHttpApiData BasicAuthToken where parseHeader h = BasicAuthToken <$> parseHeaderWithPrefix "Basic " h parseQueryParam p = BasicAuthToken <$> parseQueryParam p
>>>
parseHeader "Basic QWxhZGRpbjpvcGVuIHNlc2FtZQ==" :: Either Text BasicAuthToken
Right (BasicAuthToken "QWxhZGRpbjpvcGVuIHNlc2FtZQ==")
parseQueryParamWithPrefix :: FromHttpApiData a => Text -> Text -> Either Text a Source #
Case insensitive.
Parse given text case insensitive and then parse the rest of the input
using
.parseQueryParam
>>>
parseQueryParamWithPrefix "z" "z10" :: Either Text Int
Right 10
Multiple URL pieces
toUrlPieces :: (Functor t, ToHttpApiData a) => t a -> t Text Source #
Convert multiple values to a list of URL pieces.
>>>
toUrlPieces [1, 2, 3] :: [Text]
["1","2","3"]
parseUrlPieces :: (Traversable t, FromHttpApiData a) => t Text -> Either Text (t a) Source #
Parse multiple URL pieces.
>>>
parseUrlPieces ["true", "false"] :: Either Text [Bool]
Right [True,False]>>>
parseUrlPieces ["123", "hello", "world"] :: Either Text [Int]
Left "could not parse: `hello' (input does not start with a digit)"
Multiple query params
toQueryParams :: (Functor t, ToHttpApiData a) => t a -> t Text Source #
Convert multiple values to a list of query parameter values.
>>>
toQueryParams [fromGregorian 2015 10 03, fromGregorian 2015 12 01] :: [Text]
["2015-10-03","2015-12-01"]
parseQueryParams :: (Traversable t, FromHttpApiData a) => t Text -> Either Text (t a) Source #
Parse multiple query parameters.
>>>
parseQueryParams ["1", "2", "3"] :: Either Text [Int]
Right [1,2,3]>>>
parseQueryParams ["64", "128", "256"] :: Either Text [Word8]
Left "out of bounds: `256' (should be between 0 and 255)"
Parsers for Bounded
Enum
s
Bounded
Enum
parseBoundedUrlPiece :: (ToHttpApiData a, Bounded a, Enum a) => Text -> Either Text a Source #
Case insensitive.
Parse values case insensitively based on
instance.
Uses ToHttpApiData
to get possible values.toUrlPiece
parseBoundedQueryParam :: (ToHttpApiData a, Bounded a, Enum a) => Text -> Either Text a Source #
Case insensitive.
Parse values case insensitively based on
instance.
Uses ToHttpApiData
to get possible values.toQueryParam
parseBoundedHeader :: (ToHttpApiData a, Bounded a, Enum a) => ByteString -> Either Text a Source #
Parse values based on
instance.
Uses ToHttpApiData
to get possible values.toHeader
parseBoundedEnumOf :: (Bounded a, Enum a) => (a -> Text) -> Text -> Either Text a Source #
Parse values based on a precalculated mapping of their
representation.Text
>>>
parseBoundedEnumOf toUrlPiece "true" :: Either Text Bool
Right True
For case insensitive parser see parseBoundedEnumOfI
.
parseBoundedEnumOfI :: (Bounded a, Enum a) => (a -> Text) -> Text -> Either Text a Source #
Case insensitive.
Parse values case insensitively based on a precalculated mapping
of their
representations.Text
>>>
parseBoundedEnumOfI toUrlPiece "FALSE" :: Either Text Bool
Right False
For case sensitive parser see parseBoundedEnumOf
.
parseBoundedTextData :: (Show a, Bounded a, Enum a) => Text -> Either Text a Source #
Case insensitive.
Parse values case insensitively based on
instance.Show
>>>
parseBoundedTextData "true" :: Either Text Bool
Right True>>>
parseBoundedTextData "FALSE" :: Either Text Bool
Right False
This can be used as a default implementation for enumeration types:
>>>
data MyData = Foo | Bar | Baz deriving (Show, Bounded, Enum)
>>>
instance FromHttpApiData MyData where parseUrlPiece = parseBoundedTextData
>>>
parseUrlPiece "foo" :: Either Text MyData
Right Foo
Lenient data
newtype LenientData a Source #
Lenient parameters. FromHttpApiData
combinators always return Right
.
Since: 0.3.5
Instances
Other helpers
showTextData :: Show a => a -> Text Source #
Lower case.
Convert to URL piece using
instance.
The result is always lower cased.Show
>>>
showTextData True
"true"
This can be used as a default implementation for enumeration types:
>>>
data MyData = Foo | Bar | Baz deriving (Show)
>>>
instance ToHttpApiData MyData where toUrlPiece = showTextData
>>>
toUrlPiece Foo
"foo"
readTextData :: Read a => Text -> Either Text a Source #
Parse URL piece using
instance.Read
Use for types which do not involve letters:
>>>
readTextData "1991-06-02" :: Either Text Day
Right 1991-06-02
This parser is case sensitive and will not match
in presence of letters:showTextData
>>>
readTextData (showTextData True) :: Either Text Bool
Left "could not parse: `true'"
See
.parseBoundedTextData