improvement: warn on api missing from config

config/config.exs

@@ -28,4 +28,5 @@ if Mix.env() == :test do
   ]
 
   config :ash, :validate_api_resource_inclusion?, false
+  config :ash, :validate_api_config_inclusion?, false
 end

lib/ash/api/api.ex

@@ -36,7 +36,14 @@ defmodule Ash.Api do
   Additionally, you can define a `code_interface` on each resource. See the code interface guide for more.
   """
 
-  use Spark.Dsl, default_extensions: [extensions: [Ash.Api.Dsl]]
+  use Spark.Dsl,
+    default_extensions: [extensions: [Ash.Api.Dsl]],
+    opt_schema: [
+      validate_config_inclusion?: [
+        type: :boolean,
+        default: true
+      ]
+    ]
 
   import Spark.OptionsHelpers, only: [merge_schemas: 3]
 
@@ -1398,6 +1405,36 @@ defmodule Ash.Api do
     end
   end
 
+  @impl true
+  def verify(module, opts) do
+    if Application.get_env(:ash, :validate_api_config_inclusion?, true) &&
+         Keyword.get(opts, :validate_config_inclusion?, true) do
+      otp_app = Mix.Project.config()[:app]
+
+      apis =
+        Application.get_env(otp_app, :ash_apis, [])
+
+      if module not in apis do
+        IO.warn("""
+        Api #{inspect(module)} is not present in
+
+            config :#{otp_app}, ash_apis: #{inspect(apis)}.
+
+
+        To resolve this warning, do one of the following.
+
+        1. Add the api to your configured api modules. The following snippet can be used.
+
+            config :#{otp_app}, ash_apis: #{inspect(apis ++ [module])}
+
+        2. Add the option `validate_config_inclusion?: false` to `use Ash.Api`
+
+        3. Configure all apis not to warn, with `config :ash, :validate_api_config_inclusion?, false`
+        """)
+      end
+    end
+  end
+
   @doc false
   # sobelow_skip ["DOS.StringToAtom"]
   @impl Spark.Dsl

lib/ash/embeddable_type.ex

@@ -61,7 +61,7 @@ defmodule Ash.EmbeddableType do
 
   defmodule ShadowApi do
     @moduledoc false
-    use Ash.Api
+    use Ash.Api, validate_config_inclusion?: false
 
     resources do
       allow_unregistered?(true)

lib/ash/filter/filter.ex

@@ -192,7 +192,7 @@ defmodule Ash.Filter do
   # Used for fetching related data in filters, which will have already had authorization rules applied
   defmodule ShadowApi do
     @moduledoc false
-    use Ash.Api
+    use Ash.Api, validate_config_inclusion?: false
 
     resources do
       allow_unregistered?(true)

lib/ash/resource.ex

@@ -17,6 +17,12 @@ defmodule Ash.Resource do
     default_extensions: [
       data_layer: Ash.DataLayer.Simple,
       extensions: [Ash.Resource.Dsl]
+    ],
+    opt_schema: [
+      validate_api_inclusion?: [
+        type: :boolean,
+        default: true
+      ]
     ]
 
   @doc false