fix: camelize nested keys in read action typed map metadata

lib/ash_typescript/rpc/pipeline.ex

@@ -1341,7 +1341,14 @@ defmodule AshTypescript.Rpc.Pipeline do
        when is_map(filtered_record) do
     metadata_map = Map.get(original_record, :__metadata__, %{})
     extracted_metadata = extract_metadata_fields(metadata_map, show_metadata, rpc_action)
-    Map.merge(filtered_record, extracted_metadata)
+    formatter = Rpc.output_field_formatter()
+
+    formatted_metadata =
+      Enum.into(extracted_metadata, %{}, fn {key, value} ->
+        {key, format_field_names(value, formatter)}
+      end)
+
+    Map.merge(filtered_record, formatted_metadata)
   end
 
   defp do_add_read_metadata(filtered_record, _original_record, _show_metadata, _rpc_action) do

test/ash_typescript/rpc/rpc_metadata_test.exs

@@ -729,6 +729,38 @@ defmodule AshTypescript.Rpc.MetadataTest do
     end
   end
 
+  describe "READ actions - typed map metadata nested key formatting" do
+    test "typed map metadata values have camelCase nested keys" do
+      task = create_task("Test Task")
+
+      params = %{
+        "action" => "read_tasks_with_typed_map_metadata",
+        "fields" => ["id", "title"],
+        "metadataFields" => ["auditEntries", "completionInfo"]
+      }
+
+      conn = %Plug.Conn{}
+      result = Rpc.run_action(:ash_typescript, conn, params)
+
+      assert result["success"] == true
+      tasks = result["data"]
+      task_result = Enum.find(tasks, &(&1["id"] == task.id))
+
+      # Nested keys in {:array, :map} metadata should be camelCase
+      first_entry = List.first(task_result["auditEntries"])
+      assert first_entry["fieldName"] == "title"
+      assert first_entry["oldValue"] == "Old Title"
+      refute Map.has_key?(first_entry, "field_name")
+      refute Map.has_key?(first_entry, "old_value")
+
+      # Nested keys in :map metadata should be camelCase
+      assert task_result["completionInfo"]["completedAt"] == "2025-01-15T10:30:00Z"
+      assert task_result["completionInfo"]["completedBy"] == "user_123"
+      refute Map.has_key?(task_result["completionInfo"], "completed_at")
+      refute Map.has_key?(task_result["completionInfo"], "completed_by")
+    end
+  end
+
   # Helper function to create tasks
   defp create_task(title) do
     Task

test/support/domain.ex

@@ -211,6 +211,9 @@ defmodule AshTypescript.Test.Domain do
       rpc_action :destroy_task_metadata_empty, :destroy, show_metadata: []
       rpc_action :destroy_task_metadata_one, :destroy, show_metadata: [:some_string]
       rpc_action :destroy_task_metadata_two, :destroy, show_metadata: [:some_string, :some_number]
+
+      rpc_action :read_tasks_with_typed_map_metadata, :read_with_typed_map_metadata,
+        show_metadata: nil
     end
 
     resource AshTypescript.Test.PostComment

test/support/resources/task.ex

@@ -89,6 +89,45 @@ defmodule AshTypescript.Test.Task do
       end
     end
 
+    read :read_with_typed_map_metadata do
+      metadata :audit_entries, {:array, :map},
+        constraints: [
+          items: [
+            fields: [
+              field_name: [type: :string],
+              old_value: [type: :string]
+            ]
+          ]
+        ]
+
+      metadata :completion_info, :map,
+        constraints: [
+          fields: [
+            completed_at: [type: :string],
+            completed_by: [type: :string]
+          ]
+        ]
+
+      prepare fn query, _context ->
+        Ash.Query.after_action(query, fn _query, results ->
+          results_with_metadata =
+            Enum.map(results, fn record ->
+              record
+              |> Ash.Resource.put_metadata(:audit_entries, [
+                %{field_name: "title", old_value: "Old Title"},
+                %{field_name: "completed", old_value: "false"}
+              ])
+              |> Ash.Resource.put_metadata(:completion_info, %{
+                completed_at: "2025-01-15T10:30:00Z",
+                completed_by: "user_123"
+              })
+            end)
+
+          {:ok, results_with_metadata}
+        end)
+      end
+    end
+
     read :read_with_invalid_metadata_names do
       metadata :meta_1, :string, allow_nil?: false, default: "metadata_value"
       metadata :is_valid?, :boolean, allow_nil?: false, default: true