Working s3 compatible file uplaods!

lib/mixer/posts.ex

@@ -19,5 +19,9 @@ defmodule Mixer.Posts do
       rpc_action :update_tweet, :update
       rpc_action :destroy_tweet, :destroy
     end
+
+    resource Mixer.Posts.Media do
+      rpc_action :read_media, :read
+    end
   end
 end

lib/mixer/posts/media.ex

@@ -5,7 +5,6 @@ defmodule Mixer.Posts.Media do
     data_layer: AshPostgres.DataLayer,
     authorizers: [Ash.Policy.Authorizer],
     extensions: [
-      #AshStateMachine,
       AshTypescript.Resource
     ]
 
@@ -19,7 +18,20 @@ defmodule Mixer.Posts.Media do
   end
 
   actions do
-    defaults [:read, :destroy, create: :*, update: :*]
+    defaults [:read]
+
+    create :upload do
+      accept [:s3_key]
+      change relate_actor(:user)
+    end
+
+    update :link_to_tweet do
+      accept [:tweet_id]
+    end
+
+    destroy :destroy do
+      primary? true
+    end
   end
 
   attributes do
@@ -29,12 +41,41 @@ defmodule Mixer.Posts.Media do
       allow_nil? false
       public? true
     end
-  end
 
-  relationships do
-    belongs_to :tweet, Mixer.Posts.Tweet do
+    attribute :user_id, :uuid do
       allow_nil? false
       public? true
     end
   end
+
+  relationships do
+    belongs_to :user, Mixer.Accounts.User do
+      attribute_writable? true
+      allow_nil? false
+      public? true
+    end
+
+    belongs_to :tweet, Mixer.Posts.Tweet do
+      allow_nil? true
+      public? true
+    end
+  end
+
+  policies do
+    policy action_type(:read) do
+      authorize_if always()
+    end
+
+    policy action(:upload) do
+      authorize_if actor_present()
+    end
+
+    policy action(:link_to_tweet) do
+      authorize_if relates_to_actor_via(:user)
+    end
+
+    policy action_type(:destroy) do
+      authorize_if relates_to_actor_via(:user)
+    end
+  end
 end

lib/mixer/posts/media_uploader.ex

@@ -0,0 +1,24 @@
+defmodule Mixer.Posts.MediaUploader do
+  use Waffle.Definition
+
+  @async false
+  @versions [:original]
+  @extensions ~w(.jpg .jpeg .png .gif .webp .mp4 .mov)
+
+  def validate({file, _scope}) do
+    ext = file.file_name |> Path.extname() |> String.downcase()
+    if ext in @extensions, do: :ok, else: {:error, "unsupported file type #{ext}"}
+  end
+
+  def storage_dir(_version, {_file, scope}), do: "uploads/media/#{scope.id}"
+
+  def filename(_version, {file, _scope}) do
+    Path.basename(file.file_name, Path.extname(file.file_name))
+  end
+
+  def s3_object_headers(_version, {file, _scope}) do
+    [content_type: MIME.from_path(file.file_name)]
+  end
+
+  def acl(_version, _), do: :public_read
+end

lib/mixer/posts/tweet.ex

@@ -30,8 +30,25 @@ defmodule Mixer.Posts.Tweet do
     create :create do
       upsert? true
       accept [:content]
+      argument :media_id, :uuid, allow_nil?: true
       change relate_actor(:user)
       change transition_state(:posted)
+      change fn changeset, context ->
+        case Ash.Changeset.get_argument(changeset, :media_id) do
+          nil ->
+            changeset
+
+          media_id ->
+            Ash.Changeset.after_action(changeset, fn _changeset, tweet ->
+              Mixer.Posts.Media
+              |> Ash.get!(media_id, authorize?: false)
+              |> Ash.Changeset.for_update(:link_to_tweet, %{tweet_id: tweet.id})
+              |> Ash.update!(actor: context.actor)
+
+              {:ok, tweet}
+            end)
+        end
+      end
     end
   end
 
@@ -63,7 +80,7 @@ defmodule Mixer.Posts.Tweet do
       public? true
     end
 
-    has_many :s3_key, Mixer.Posts.Media do
+    has_many :media, Mixer.Posts.Media do
       public? true
     end
   end