CHANGELOG.md

@@ -5,6 +5,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [0.12.2.0]
+
+### Added
+
+- `FromHttpApiData` instance for Servant integration
+
 ## [0.12.0]
 
 ### Added

hexstring.cabal

@@ -39,6 +39,7 @@ library
     , bytestring
     , foreign-rust
     , generics-sop
+    , servant
     , text
   default-language: Haskell2010
 

package.yaml

@@ -1,5 +1,5 @@
 name: hexstring
-version: 0.12.1.0
+version: 0.12.2.0
 git: "https://git.vergara.tech/Vergara_Tech/haskell-hexstring"
 license: MIT
 author:
@@ -30,6 +30,7 @@ library:
     - generics-sop
     - borsh >= 0.2
     - foreign-rust
+    - servant
 
 tests:
   hextring-test:

src/Data/HexString.hs

@@ -35,6 +35,8 @@ import qualified GHC.Generics as GHC
 import qualified Generics.SOP as SOP
 import Text.Read
 
+import Servant.API (FromHttpApiData(..))
+
 -- | Represents a Hex string. Guarantees that all characters it contains
 --   are valid hex characters.
 newtype HexString = HexString
@@ -56,6 +58,12 @@ instance FromJSON HexString where
 instance ToJSON HexString where
   toJSON = Data.Aeson.String . toText
 
+instance FromHttpApiData HexString where
+  parseUrlPiece s =
+    case BS16.decode (TE.encodeUtf8 s) of
+      Right s -> Right $ HexString s
+      Left e -> Left $ T.pack e
+
 -- | Smart constructor which validates that all the text are actually
 --   hexadecimal characters.
 hexString :: BS.ByteString -> HexString