keep_defaults?

Author: jechol

lib/transformer.ex

@@ -15,11 +15,12 @@ defmodule AshRandomParams.Transformer do
     init_params = Builder.build_action_argument(:init_params, :map, default: %{})
     fill = Builder.build_action_argument(:fill, {:array, :atom}, default: [])
     unfill = Builder.build_action_argument(:unfill, {:array, :atom}, default: [])
+    keep_defaults? = Builder.build_action_argument(:keep_defaults?, :boolean, default: true)
 
     dsl_state
     |> Builder.add_action(:action, :random_params,
       returns: :map,
-      arguments: [action, init_params, unfill, fill],
+      arguments: [action, init_params, unfill, fill, keep_defaults?],
       run: &__MODULE__.do_random_params/2
     )
     |> Builder.add_interface(:random_params, args: [:action, {:optional, :init_params}])
@@ -44,15 +45,13 @@ defmodule AshRandomParams.Transformer do
             action: action,
             init_params: init_params,
             unfill: unfill,
-            fill: fill
+            fill: fill,
+            keep_defaults?: keep_defaults?
           }
         } =
           input,
         ctx
       ) do
-    {random_mod, random_opts} =
-      random = AshRandomParams.Info.random_params_random!(input.resource)
-
     action = Ash.Resource.Info.action(resource, action)
     init_keys = init_params |> Map.keys()
 
@@ -75,21 +74,41 @@ defmodule AshRandomParams.Transformer do
 
     candidates = accepted_attrs ++ action.arguments
 
-    placeholder =
-      candidates
-      |> then(fn attr_or_args ->
-        if action.type == :create do
-          attr_or_args
-        else
-          attr_or_args
-          |> Enum.reject(&(&1.name in rel_names))
-          |> Enum.reject(&(&1.name in belongs_to_attrs))
-        end
-      end)
-      |> Map.new(&{&1.name, nil})
+    defaults =
+      if keep_defaults? do
+        candidates
+        |> then(fn attr_or_args ->
+          if action.type == :create do
+            attr_or_args
+          else
+            attr_or_args
+            |> Enum.reject(&(&1.name in rel_names))
+            |> Enum.reject(&(&1.name in belongs_to_attrs))
+          end
+        end)
+        |> Enum.reject(&(&1.name in unfill))
+        |> Enum.reject(&(&1.name in init_keys))
+        |> Map.new(fn %{name: name, default: default} ->
+          value =
+            case default do
+              default when is_function(default, 0) ->
+                default.()
+
+              default ->
+                default
+            end
+
+          {name, value}
+        end)
+      else
+        %{}
+      end
 
     generated_params =
       (
+        {random_mod, random_opts} =
+          random = AshRandomParams.Info.random_params_random!(input.resource)
+
         fields_by_unfill =
           candidates
           |> Enum.reject(&(&1.name in rel_names))
@@ -118,7 +137,7 @@ defmodule AshRandomParams.Transformer do
         end)
       )
 
-    result_params = placeholder |> Map.merge(init_params) |> Map.merge(generated_params)
+    result_params = defaults |> Map.merge(init_params) |> Map.merge(generated_params)
 
     {:ok, result_params}
   end

test/ash_random_params_test.exs

@@ -141,11 +141,11 @@ defmodule AshRandomParamsTest do
     test "with unfill" do
       assert %{
                author_id: nil,
-               req_str: nil,
                opt_str: nil,
                req_int: 777,
                opt_int: nil
              } =
+               params =
                Post
                |> Ash.ActionInput.for_action(
                  :random_params,
@@ -155,6 +155,29 @@ defmodule AshRandomParamsTest do
                  }
                )
                |> Ash.run_action!()
+
+      refute params |> Map.has_key?(:req_str)
+    end
+
+    test "with keep_defaults? false" do
+      assert %{
+               req_str: "req_str-" <> _,
+               req_int: 777
+             } =
+               params =
+               Post
+               |> Ash.ActionInput.for_action(
+                 :random_params,
+                 %{
+                   action: :create,
+                   keep_defaults?: false
+                 }
+               )
+               |> Ash.run_action!()
+
+      refute params |> Map.has_key?(:opt_str)
+      refute params |> Map.has_key?(:opt_int)
+      refute params |> Map.has_key?(:author_id)
     end
   end