fix(FCM.Error): implement recursive parsing for handling multiple elements in "details"

Refactored the `parse/1` function to use recursion for correctly handling cases where the "details" list contains multiple elements, and falling back to the "status" field when necessary.

Author: caruspi

lib/pigeon/fcm/error.ex

@@ -5,14 +5,17 @@ defmodule Pigeon.FCM.Error do
 
   @doc false
   @spec parse(map) :: Notification.error_response()
-  def parse(%{"details" => [%{"errorCode" => error_code}]}),
+  def parse(%{"details" => details} = error), do: parse_details(details, error)
+  def parse(error), do: parse_status(error)
+
+  defp parse_details([%{"errorCode" => error_code} | _], _),
     do: parse_response(error_code)
 
-  def parse(error) do
-    error
-    |> Map.get("status")
-    |> parse_response()
-  end
+  defp parse_details([_ | tail], error), do: parse_details(tail, error)
+  defp parse_details([], error), do: parse_status(error)
+
+  defp parse_status(%{"status" => status}), do: parse_response(status)
+  defp parse_status(_), do: :unknown_error
 
   defp parse_response("UNSPECIFIED_ERROR"), do: :unspecified_error
   defp parse_response("INVALID_ARGUMENT"), do: :invalid_argument

test/pigeon/fcm/error_test.exs

@@ -0,0 +1,183 @@
+defmodule Pigeon.FCM.ErrorTest do
+  use ExUnit.Case, async: true
+  alias Pigeon.FCM.Error
+
+  describe "parse/1" do
+    test "returns :unregistered when 'errorCode' is 'UNREGISTERED' in details" do
+      error = %{
+        "code" => 404,
+        "details" => [
+          %{
+            "@type" => "type.googleapis.com/google.firebase.fcm.v1.FcmError",
+            "errorCode" => "UNREGISTERED"
+          },
+          %{
+            "@type" => "type.googleapis.com/google.firebase.fcm.v1.ApnsError",
+            "reason" => "Unregistered",
+            "statusCode" => 410
+          }
+        ],
+        "message" => "Requested entity was not found.",
+        "status" => "NOT_FOUND"
+      }
+
+      assert Error.parse(error) == :unregistered
+    end
+
+    test "returns :invalid_argument when 'errorCode' is 'INVALID_ARGUMENT' in details" do
+      error = %{
+        "code" => 400,
+        "details" => [
+          %{
+            "@type" => "type.googleapis.com/google.firebase.fcm.v1.FcmError",
+            "errorCode" => "INVALID_ARGUMENT"
+          }
+        ],
+        "message" => "Bad request.",
+        "status" => "NOT_FOUND"
+      }
+
+      assert Error.parse(error) == :invalid_argument
+    end
+
+    test "returns :unknown_error when 'errorCode' is not found in details and 'status' is missing" do
+      error = %{
+        "code" => 500,
+        "details" => [
+          %{
+            "@type" => "type.googleapis.com/google.firebase.fcm.v1.FcmError",
+            "reason" => "Unknown"
+          }
+        ],
+        "message" => "Internal server error."
+      }
+
+      assert Error.parse(error) == :unknown_error
+    end
+
+    test "returns :quota_exceeded when 'errorCode' is 'QUOTA_EXCEEDED'" do
+      error = %{
+        "code" => 429,
+        "details" => [
+          %{
+            "@type" => "type.googleapis.com/google.firebase.fcm.v1.FcmError",
+            "errorCode" => "QUOTA_EXCEEDED"
+          }
+        ],
+        "message" => "Quota exceeded.",
+        "status" => "NOT_FOUND"
+      }
+
+      assert Error.parse(error) == :quota_exceeded
+    end
+
+    test "returns :unavailable when 'errorCode' is 'UNAVAILABLE'" do
+      error = %{
+        "code" => 503,
+        "details" => [
+          %{
+            "@type" => "type.googleapis.com/google.firebase.fcm.v1.FcmError",
+            "errorCode" => "UNAVAILABLE"
+          }
+        ],
+        "message" => "Service unavailable.",
+        "status" => "NOT_FOUND"
+      }
+
+      assert Error.parse(error) == :unavailable
+    end
+
+    test "returns :internal when 'errorCode' is 'INTERNAL'" do
+      error = %{
+        "code" => 500,
+        "details" => [
+          %{
+            "@type" => "type.googleapis.com/google.firebase.fcm.v1.FcmError",
+            "errorCode" => "INTERNAL"
+          }
+        ],
+        "message" => "Internal server error.",
+        "status" => "NOT_FOUND"
+      }
+
+      assert Error.parse(error) == :internal
+    end
+
+    test "returns :third_party_auth_error when 'errorCode' is 'THIRD_PARTY_AUTH_ERROR'" do
+      error = %{
+        "code" => 401,
+        "details" => [
+          %{
+            "@type" => "type.googleapis.com/google.firebase.fcm.v1.FcmError",
+            "errorCode" => "THIRD_PARTY_AUTH_ERROR"
+          }
+        ],
+        "message" => "Third-party authentication error.",
+        "status" => "NOT_FOUND"
+      }
+
+      assert Error.parse(error) == :third_party_auth_error
+    end
+
+    test "returns :permission_denied when 'errorCode' is 'PERMISSION_DENIED'" do
+      error = %{
+        "code" => 403,
+        "details" => [
+          %{
+            "@type" => "type.googleapis.com/google.firebase.fcm.v1.FcmError",
+            "errorCode" => "PERMISSION_DENIED"
+          }
+        ],
+        "message" => "Permission denied.",
+        "status" => "NOT_FOUND"
+      }
+
+      assert Error.parse(error) == :permission_denied
+    end
+
+    test "returns :unknown_error when 'errorCode' is unknown in details" do
+      error = %{
+        "code" => 400,
+        "details" => [
+          %{
+            "@type" => "type.googleapis.com/google.firebase.fcm.v1.FcmError",
+            "errorCode" => "UNKNOWN_ERROR"
+          }
+        ],
+        "message" => "Unknown error.",
+        "status" => "NOT_FOUND"
+      }
+
+      assert Error.parse(error) == :unknown_error
+    end
+
+    test "returns :invalid_argument when 'status' is 'INVALID_ARGUMENT'" do
+      error = %{
+        "code" => 400,
+        "status" => "INVALID_ARGUMENT",
+        "message" => "Bad request."
+      }
+
+      assert Error.parse(error) == :invalid_argument
+    end
+
+    test "returns :unknown_error when 'status' is not found" do
+      error = %{
+        "code" => 500,
+        "message" => "Unknown error."
+      }
+
+      assert Error.parse(error) == :unknown_error
+    end
+
+    test "returns :unknown_error when 'status' is unknown" do
+      error = %{
+        "code" => 500,
+        "status" => "UNKNOWN_STATUS",
+        "message" => "Unknown status error."
+      }
+
+      assert Error.parse(error) == :unknown_error
+    end
+  end
+end