fix(fcm): look at the errorCode instead of status when parsing FCM errors

CHANGELOG.md

@@ -7,7 +7,8 @@
 - Resolve APNS `:too_many_provider_token_updates` by moving token generation into
   `APNS.Token` ([#227](https://github.com/codedge-llc/pigeon/pull/227)).
 - Support HTTPoison 2.0. ([#236](https://github.com/codedge-llc/pigeon/pull/236))
-- Fix `DispatcherWorker` missing a clause for `{:stop, reason}` in the init function
+- Improve handling of FCM error responses. ([#245](https://github.com/codedge-llc/pigeon/pull/245))
+- Fix `DispatcherWorker` missing a clause for `{:stop, reason}` in the init function.
 - `APNS.Config` keys now decode properly for PEMs generated with OpenSSL 3. ([#248](https://github.com/codedge-llc/pigeon/pull/248))
 - Add `ExpiredToken` as APNS error response. ([#240](https://github.com/codedge-llc/pigeon/pull/240))
 - Better handling of APNS token lifecycle between `:dev`/`:prod` environments with the same key identifier. ([#239](https://github.com/codedge-llc/pigeon/pull/239))

lib/pigeon/fcm/error.ex

@@ -5,6 +5,9 @@ defmodule Pigeon.FCM.Error do
 
   @doc false
   @spec parse(map) :: Notification.error_response()
+  def parse(%{"details" => [%{"errorCode" => error_code}]}),
+    do: parse_response(error_code)
+
   def parse(error) do
     error
     |> Map.get("status")
@@ -19,5 +22,5 @@ defmodule Pigeon.FCM.Error do
   defp parse_response("UNAVAILABLE"), do: :unavailable
   defp parse_response("INTERNAL"), do: :internal
   defp parse_response("THIRD_PARTY_AUTH_ERROR"), do: :third_party_auth_error
-  defp parse_response(_), do: :unknown_error
+  defp parse_response(_other), do: :unknown_error
 end

lib/pigeon/fcm/notification.ex

@@ -40,6 +40,7 @@ defmodule Pigeon.FCM.Notification do
           | :unavailable
           | :internal
           | :third_party_auth_error
+          | :unknown_error
 
   @typedoc ~S"""
   FCM notification target. Must be one of the following: