Enhance encoding of hex memos

CHANGELOG.md

@@ -6,13 +6,20 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Changed
+
+- Enhance `decodeHexText` to support Unicode
+- Enhance `encodeHexText` to support Unicode
+
+## [0.1.0.2] - 2022-05-25
+
 ### Added
 
 - Changelog
 - `paid` field in ZGoOrder type
 - Test for `api/order/:id` endpoint with an invalid ID
 
-## Fixed
+### Fixed
 
 - Bug #1: crash when invalid ID was provided to `api/order/:id`
 

src/ZGoBackend.hs

@@ -14,6 +14,7 @@ import qualified Data.Bson as B
 import qualified Data.ByteString as BS
 import Data.Char
 import qualified Data.HashMap.Strict as HM
+import Data.HexString
 import Data.Maybe
 import Data.SecureMem
 import qualified Data.Text as T
@@ -162,13 +163,8 @@ decodeHexText h = E.decodeUtf8With lenientDecode $ BS.pack $ hexRead h
         chunk = take 2 hexText
 
 -- | Helper function to turn a string into a hex-encoded string
-encodeHexText :: String -> String
+encodeHexText :: T.Text -> String
-encodeHexText t = mconcat (map padHex t)
+encodeHexText t = T.unpack . toText . fromBytes $ E.encodeUtf8 t
-  where
-    padHex x =
-      if ord x < 16
-        then "0" ++ (showHex . ord) x ""
-        else showHex (ord x) ""
 
 -- Types for the ZGo database documents
 -- | Type to model a country for the database's country list
@@ -258,7 +254,7 @@ sendPin nodeUser nodePwd nodeAddress addr pin = do
                [ object
                    [ "address" .= addr
                    , "amount" .= (0.00000001 :: Double)
-                   , "memo" .= encodeHexText ("ZGo PIN: " ++ T.unpack pin)
+                   , "memo" .= encodeHexText ("ZGo PIN: " <> pin)
                    ]
                ])
         ]