Keep in-editor asset curation off the head, layering it like every edit

ensure_autosave! gives body keystrokes and asset curation one shared
layer, so head is never mutated in place and every curation change
surfaces in the publish delta. Stale rendered join ids are mapped
across the clone via asset_id. Curation now requires holding the
lock; a missing lock answers 423, matching the autosave endpoint.

3 files changed, 55 insertions, 19 deletions

diff --git a/app/controllers/related_assets_controller.rb b/app/controllers/related_assets_controller.rb
index ca894f2f..3aa6d3db 100644
--- a/app/controllers/related_assets_controller.rb
+++ b/app/controllers/related_assets_controller.rb
@@ -2,6 +2,10 @@ class RelatedAssetsController < ApplicationController
   before_action :login_required
   before_action :find_node
 
+  rescue_from LockedByAnotherUser do
+    head :locked
+  end
+
   def search
     term = params[:search_term].to_s.strip
     attached_ids = @node.editable_page.related_assets.pluck(:asset_id)
@@ -19,8 +23,9 @@ class RelatedAssetsController < ApplicationController
   end
 
   def create
+    page  = @node.ensure_autosave!(current_user)
     asset = Asset.find(params[:asset_id])
-    related = @node.editable_page.related_assets.find_or_create_by!(asset: asset)
+    related = page.related_assets.find_or_create_by!(asset: asset)
 
     render json: {
       id: related.id,
@@ -35,22 +40,25 @@ class RelatedAssetsController < ApplicationController
   end
 
   def destroy
-    @node.editable_page.related_assets.find(params[:id]).destroy
+    page   = @node.ensure_autosave!(current_user)
+    source = RelatedAsset.find(params[:id])
+    page.related_assets.find_by!(:asset_id => source.asset_id).destroy
     head :ok
   end
 
   def update
-    related = @node.editable_page.related_assets.find(params[:id])
+    page    = @node.ensure_autosave!(current_user)
+    source  = RelatedAsset.find(params[:id])
+    related = page.related_assets.find_by!(:asset_id => source.asset_id)
 
     if params.key?(:headline)
       RelatedAsset.transaction do
-        @node.editable_page.related_assets.update_all(headline: false)
+        page.related_assets.update_all(headline: false)
         related.update!(headline: true) if params[:headline] == "true"
       end
     else
       related.insert_at(params[:position].to_i)
     end
-
     head :ok
   end
 
diff --git a/app/models/node.rb b/app/models/node.rb
index 274b2f94..02502f6c 100644
--- a/app/models/node.rb
+++ b/app/models/node.rb
@@ -112,18 +112,18 @@ class Node < ApplicationRecord
     end
   end
 
-  # Creates or updates the autosave buffer from the given attributes.
-  # Autosave rows are never associated to the node via node_id -- they
-  # must never appear in self.pages / the revisions list, which is the
-  # whole reason autosave exists as a separate, unversioned layer.
-  def autosave! attributes, current_user
+  def ensure_autosave! current_user
     assert_locked_by! current_user
-
     unless self.autosave
       self.autosave = Page.create!(:editor => current_user)
       self.autosave.clone_attributes_from(self.draft || self.head) if self.draft || self.head
       self.save!
     end
+    self.autosave
+  end
+
+  def autosave! attributes, current_user
+    ensure_autosave!(current_user)
     self.autosave.assign_attributes(attributes)
     self.autosave.save!
     self.autosave
diff --git a/test/controllers/related_assets_controller_test.rb b/test/controllers/related_assets_controller_test.rb
index ced4b74d..fd30dddd 100644
--- a/test/controllers/related_assets_controller_test.rb
+++ b/test/controllers/related_assets_controller_test.rb
@@ -38,19 +38,24 @@ class RelatedAssetsControllerTest < ActionController::TestCase
   test "create attaches an asset to the node's editable page" do
     login_as :quentin
     node = Node.root.children.create!(:slug => "related_assets_create_test")
+    node.lock_for_editing!(users(:quentin))
     asset = Asset.create!(:name => "erfa-photo", :upload_content_type => "image/png")
 
     post :create, params: { :node_id => node.id, :asset_id => asset.id }
 
     assert_response :success
-    assert_includes node.draft.reload.related_assets.map(&:asset_id), asset.id
+    current = node.reload.editable_page
+    assert_equal node.autosave, current, "mutation should have created an autosave layer"
+    assert_includes current.related_assets.map(&:asset_id), asset.id
     json = JSON.parse(response.body)
     assert json["url"].present?
+    assert_empty node.draft.reload.related_assets, "the draft must stay untouched"
   end
 
   test "create does not duplicate an already-attached asset" do
     login_as :quentin
     node = Node.root.children.create!(:slug => "related_assets_dup_test")
+    node.lock_for_editing!(users(:quentin))
     asset = Asset.create!(:name => "erfa-photo-2", :upload_content_type => "image/png")
     node.draft.assets << asset
 
@@ -63,19 +68,22 @@ class RelatedAssetsControllerTest < ActionController::TestCase
   test "destroy removes the attached asset" do
     login_as :quentin
     node = Node.root.children.create!(:slug => "related_assets_destroy_test")
+    node.lock_for_editing!(users(:quentin))
     asset = Asset.create!(:name => "old-photo", :upload_content_type => "image/png")
     node.draft.assets << asset
-    related = node.draft.related_assets.first
 
+    related = node.draft.related_assets.first
     delete :destroy, params: { :node_id => node.id, :id => related.id }
 
     assert_response :success
-    assert_equal 0, node.draft.reload.related_assets.count
+    assert_equal 0, node.reload.editable_page.related_assets.count
+    assert_equal 1, node.draft.reload.related_assets.count, "the draft must stay untouched"
   end
 
   test "update reorders the attached assets" do
     login_as :quentin
     node = Node.root.children.create!(:slug => "related_assets_reorder_test")
+    node.lock_for_editing!(users(:quentin))
     first  = Asset.create!(:name => "first-photo", :upload_content_type => "image/png")
     second = Asset.create!(:name => "second-photo", :upload_content_type => "image/png")
     node.draft.assets << first
@@ -85,13 +93,15 @@ class RelatedAssetsControllerTest < ActionController::TestCase
     patch :update, params: { :node_id => node.id, :id => second_related.id, :position => 1 }
 
     assert_response :success
-    ordered_asset_ids = node.draft.reload.related_assets.map(&:asset_id)
+    ordered_asset_ids = node.reload.editable_page.related_assets.order(:position).map(&:asset_id)
+    # XXXX ordered_asset_ids = node.draft.reload.related_assets.map(&:asset_id)
     assert_equal [second.id, first.id], ordered_asset_ids
   end
 
   test "update sets the headline flag" do
     login_as :quentin
     node = Node.root.children.create!(:slug => "related_assets_headline_test")
+    node.lock_for_editing!(users(:quentin))
     asset = Asset.create!(:name => "headline-photo", :upload_content_type => "image/png")
     node.draft.assets << asset
     related = node.draft.related_assets.find_by(:asset_id => asset.id)
@@ -99,12 +109,14 @@ class RelatedAssetsControllerTest < ActionController::TestCase
     patch :update, params: { :node_id => node.id, :id => related.id, :headline => "true" }
 
     assert_response :success
-    assert related.reload.headline?
+    assert node.reload.editable_page.related_assets.find_by!(:asset_id => asset.id).headline?
+    assert_not related.reload.headline?, "the draft must stay untouched"
   end
 
   test "update with headline=true clears any previous headline on the same page" do
     login_as :quentin
     node = Node.root.children.create!(:slug => "related_assets_headline_swap_test")
+    node.lock_for_editing!(users(:quentin))
     first  = Asset.create!(:name => "first-headline", :upload_content_type => "image/png")
     second = Asset.create!(:name => "second-headline", :upload_content_type => "image/png")
     node.draft.assets << first
@@ -117,13 +129,16 @@ class RelatedAssetsControllerTest < ActionController::TestCase
     patch :update, params: { :node_id => node.id, :id => second_related.id, :headline => "true" }
 
     assert_response :success
-    assert_not first_related.reload.headline?
-    assert second_related.reload.headline?
+    current = node.reload.editable_page
+    assert_not current.related_assets.find_by!(:asset_id => first.id).headline?
+    assert current.related_assets.find_by!(:asset_id => second.id).headline?
+    assert first_related.reload.headline?, "the draft must stay untouched"
   end
 
   test "update with headline=false clears the headline" do
     login_as :quentin
     node = Node.root.children.create!(:slug => "related_assets_headline_unset_test")
+    node.lock_for_editing!(users(:quentin))
     asset = Asset.create!(:name => "unset-headline", :upload_content_type => "image/png")
     node.draft.assets << asset
     related = node.draft.related_assets.find_by(:asset_id => asset.id)
@@ -132,7 +147,8 @@ class RelatedAssetsControllerTest < ActionController::TestCase
     patch :update, params: { :node_id => node.id, :id => related.id, :headline => "false" }
 
     assert_response :success
-    assert_not related.reload.headline?
+    assert_not node.reload.editable_page.related_assets.find_by!(:asset_id => asset.id).headline?
+    assert related.reload.headline?, "the draft must stay untouched"
   end
 
   test "search includes PDF assets as headline-eligible candidates" do
@@ -159,4 +175,16 @@ class RelatedAssetsControllerTest < ActionController::TestCase
     ids = JSON.parse(response.body).map { |r| r["id"] }
     assert_includes ids, asset.id
   end
+
+  test "curation without holding the lock is refused with 423" do
+    login_as :quentin
+    node  = Node.root.children.create!(:slug => "curation_lock_test")
+    asset = Asset.create!(:name => "Untouchable", :upload_content_type => "image/png")
+    node.lock_for_editing!(users(:aaron))
+
+    post :create, params: { :node_id => node.id, :asset_id => asset.id }
+
+    assert_response :locked
+    assert_empty node.draft.assets.reload
+  end
 end