Attempt to implement subtlecrypto key importing (untested)

packages.dhall

@@ -124,3 +124,24 @@ with base64 =
     , version =
         "v0.0.8"  -- branch, tag, or commit hash
     }
+with subtlecrypto =
+	{ dependencies =
+		[ "aff"
+		, "aff-promise"
+		, "arraybuffer-types"
+		, "console"
+		, "effect"
+		, "either"
+		, "exceptions"
+		, "foreign"
+		, "functions"
+		, "maybe"
+		, "prelude"
+		, "transformers"
+		, "tuples"
+		, "unsafe-coerce"
+		]
+	, repo =
+		"https://github.com/xc-jp/purescript-subtlecrypto.git"
+	, version = "master"
+	}

spago.dhall

@@ -22,6 +22,7 @@ to generate this file without the comments in this block.
   , "maybe"
   , "prelude"
   , "strings"
+  , "subtlecrypto"
   ]
 , packages = ./packages.dhall
 , sources = [ "src/**/*.purs", "test/**/*.purs" ]

src/Main.purs

@@ -9,12 +9,16 @@ import Effect.Console (log)
 import Fetch (fetch)
 import Data.Binary.Base64 (decode)
 import Data.Either (Either, hush, note)
-import Data.ArrayBuffer.Types (Uint8Array)
 import Data.Maybe (Maybe(..))
 import Data.ArrayBuffer.Types (ArrayBuffer, Uint8Array)
 import Data.String (drop, indexOf', indexOf, splitAt)
 import Data.String.Pattern (Pattern(..))
 
+import Crypto.Subtle.Constants.AES (aesGCM)
+import Crypto.Subtle.Key.Import (aes)
+import Crypto.Subtle.Key.Import (importKey) as SC
+import Crypto.Subtle.Key.Types (CryptoKey, decrypt, raw)
+
 data AviaryError
     = MalformedKey
     | MalformedUrl
@@ -40,6 +44,10 @@ parseUrl url = note MalformedUrl do
 decodeKey :: String -> Either AviaryError Uint8Array
 decodeKey key = note MalformedKey $ hush $ decode key
 
+importKey :: ArrayBuffer -> Aff CryptoKey
+importKey key =
+    SC.importKey raw key (aes aesGCM) false [decrypt]
+
 main_aff :: Aff Unit
 main_aff = do
     { status, text } <- fetch "https://envs.sh/Q_V.txt" {}