Add ToForm

src/Web/WebPush.hs

@@ -59,6 +59,7 @@ import qualified Network.URI                as URI
 import           System.Random              (randomRIO)
 import           Web.FormUrlEncoded
 import           Web.HttpApiData
+import qualified Data.HashMap.Strict as HM
 
 -- | Configuration for VAPID server identification
 data VAPIDConfig = VAPIDConfig {
@@ -260,6 +261,13 @@ instance FromForm Subscription where
       , subscriptionP256dh = p256
       , subscriptionAuth = auth'
       }
+
+instance ToForm Subscription where
+  toForm sub = Form $ HM.fromList [
+      ("endpoint", [T.pack $ URI.uriToString id (subscriptionEndpoint sub) ""])
+    , ("p256dh", [subscriptionP256dh sub])
+    , ("auth", [subscriptionAuth sub])
+    ]
 
 -- | Web push notification expiration and message to send
 data PushNotification msg = PushNotification {

src/Web/WebPush/Internal.hs

@@ -128,8 +128,8 @@ webPushEncrypt EncryptionInput{..} = do -- TODO remove record wildcards
       -- tag length 16 bytes (maximum), anything less than 16 bytes may not be secure enough
       -- spec says final encrypted size is 16 bits longer than the padded text
       -- NOTE: the final encrypted message must be sent as raw binary data 
-      authTag = ByteArray.convert $ Cipher.unAuthTag authTagBytes
       (authTagBytes, cipherText) = Cipher.aeadSimpleEncrypt aeadGcmCipher BS.empty paddedPlainText 16
+      authTag = ByteArray.convert $ Cipher.unAuthTag authTagBytes
       encryptedMessage = cipherText <> authTag
       -- HMAC a doesn't have Show instance needed for test suite
       -- so we extract the bytes and store that in WebPushEncryptionOutput

web-push.cabal

@@ -31,6 +31,7 @@ library
                      , binary >= 0.7.5 && < 0.9
                      , bytestring >= 0.9 && < 0.13
                      , containers >= 0.6 && < 0.7
+                     , unordered-containers >= 0.2 && < 0.3
                      , crypton >= 0.30 && < 1.0
                      , crypton-x509 >= 1.7 && < 1.8
                      , crypton-x509-store >= 1.6 && < 1.7