Add a handle_authorize hook which is executed on all actions (before logic)

lib/ja_resource/authorize.ex

@@ -0,0 +1,24 @@
+defmodule JaResource.Authorize do
+  use Behaviour
+
+  @moduledoc """
+  Provides the `handle_authorize/0` callback used to authorize the resource.
+
+  This behaviour is used by all JaResource actions.
+  """
+
+  @doc """
+  Called before all the actions with the model. Useful for authorizing.
+  """
+  @callback handle_authorize(Plug.Conn.t, JaResource.record) :: any
+
+  defmacro __using__(_) do
+    quote do
+      @behaviour JaResource.Authorize
+
+      def handle_authorize(model, _conn), do: model
+
+      defoverridable [handle_authorize: 2]
+    end
+  end
+end

lib/ja_resource/create.ex

@@ -65,6 +65,9 @@ defmodule JaResource.Create do
   def call(controller, conn) do
     merged = JaResource.Attributes.from_params(conn.params)
     attributes = controller.permitted_attributes(conn, merged, :create)
+
+    controller.handle_authorize(controller.model(), conn)
+
     conn
     |> controller.handle_create(attributes)
     |> JaResource.Create.insert(controller)
@@ -84,7 +87,9 @@ defmodule JaResource.Create do
 
   @doc false
   def respond(%Plug.Conn{} = conn, _old_conn), do: conn
+  def respond({:error, _name, errors, _changes}, conn), do: invalid(conn, errors)
   def respond({:error, errors}, conn), do: invalid(conn, errors)
+  def respond({:ok, %{} = map}, conn), do: created(conn, Map.fetch(map, controller.atom()))
   def respond({:ok, model}, conn), do: created(conn, model)
   def respond(model, conn), do: created(conn, model)
 

lib/ja_resource/delete.ex

@@ -59,6 +59,8 @@ defmodule JaResource.Delete do
   def call(controller, conn) do
     model = controller.record(conn, conn.params["id"])
 
+    controller.handle_authorize(model, conn)
+
     conn
     |> controller.handle_delete(model)
     |> JaResource.Delete.respond(conn)
@@ -67,7 +69,9 @@ defmodule JaResource.Delete do
   @doc false
   def respond(nil, conn), do: not_found(conn)
   def respond(%Plug.Conn{} = conn, _old_conn), do: conn
+  def respond({:ok, %{} = map}, conn), do: created(conn, Map.fetch(map, controller.atom()))
   def respond({:ok, _model}, conn), do: deleted(conn)
+  def respond({:error, _name, errors, _changes}, conn), do: invalid(conn, errors)
   def respond({:errors, errors}, conn), do: invalid(conn, errors)
   def respond(_model, conn), do: deleted(conn)
 

lib/ja_resource/index.ex

@@ -119,6 +119,8 @@ defmodule JaResource.Index do
   Execute the index action on a given module implementing Index behaviour and conn.
   """
   def call(controller, conn) do
+    controller.handle_authorize(controller.model(), conn)
+
     conn
     |> controller.handle_index(conn.params)
     |> JaResource.Index.filter(conn, controller)

lib/ja_resource/model.ex

@@ -25,10 +25,20 @@ defmodule JaResource.Model do
   defmacro __using__(_) do
     quote do
       @behaviour JaResource.Model
+      use JaResource.Authorize
 
       @inferred_model JaResource.Model.model_from_controller(__MODULE__)
       def model(), do: @inferred_model
 
+      def atom() do
+        model()
+        |> Atom.to_string
+        |> String.split(".")
+        |> List.last
+        |> String.downcase
+        |> String.to_atom
+      end
+
       defoverridable [model: 0]
     end
   end

lib/ja_resource/show.ex

@@ -57,9 +57,11 @@ defmodule JaResource.Show do
   Execute the show action on a given module implementing Show behaviour and conn.
   """
   def call(controller, conn) do
-    conn
-    |> controller.handle_show(conn.params["id"])
-    |> JaResource.Show.respond(conn, controller)
+    model = controller.handle_show(conn, conn.params["id"])
+
+    controller.handle_authorize(model, conn)
+
+    JaResource.Show.respond(model, conn, controller)
   end
 
   @doc false

lib/ja_resource/update.ex

@@ -72,6 +72,8 @@ defmodule JaResource.Update do
     merged     = JaResource.Attributes.from_params(conn.params)
     attributes = controller.permitted_attributes(conn, merged, :update)
 
+    controller.handle_authorize(model, conn)
+
     conn
     |> controller.handle_update(model, attributes)
     |> JaResource.Update.update(controller)
@@ -92,7 +94,9 @@ defmodule JaResource.Update do
   @doc false
   def respond(%Plug.Conn{} = conn, _oldconn), do: conn
   def respond(nil, conn), do: send_resp(conn, :not_found, "")
+  def respond({:error, _name, errors, _changes}, conn), do: invalid(conn, errors)
   def respond({:error, errors}, conn), do: invalid(conn, errors)
+  def respond({:ok, %{} = map}, conn), do: created(conn, Map.fetch(map, controller.atom()))
   def respond({:ok, model}, conn), do: updated(conn, model)
   def respond(model, conn), do: updated(conn, model)