Add basic cache support for multiple file uploads

lib/refile/attachment/active_record.rb

@@ -35,6 +35,8 @@ def attachment(name, raise_errors: false, **options)
         end
       end
 
+      # @ignore
+      #   rubocop:disable Metrics/MethodLength
       def accepts_attachments_for(association_name, attachment: :file)
         association = reflect_on_association(association_name)
         name = "#{association_name}_#{attachment.to_s.pluralize}"
@@ -45,16 +47,29 @@ def accepts_attachments_for(association_name, attachment: :file)
           end
 
           define_method :"#{name}_data" do
-            send(association_name).map(&:"#{attachment}_data")
+            if send(association_name).all? { |record| record.send("#{attachment}_attacher").valid? }
+              send(association_name).map(&:"#{attachment}_data")
+            end
           end
 
           define_method :"#{name}" do
             send(association_name).map(&attachment)
           end
 
           define_method :"#{name}=" do |files|
-            files.select(&:present?).each do |file|
-              send(association_name).build(attachment => file)
+            cache = begin
+              JSON.parse(files.first)
+            rescue JSON::ParserError
+            end
+            files = files.drop(1)
+            if files.empty? and cache.present?
+              cache.select(&:present?).each do |file|
+                send(association_name).build(attachment => file.to_json)
+              end
+            else
+              files.select(&:present?).each do |file|
+                send(association_name).build(attachment => file)
+              end
             end
           end
         end

lib/refile/rails/attachment_helper.rb

@@ -78,9 +78,7 @@ def attachment_field(object_name, method, object:, **options)
         options[:data].merge!(direct: true).merge!(definition.cache.presign.as_json)
       end
 
-      hidden_field_name = if options[:multiple] then "#{method}[]" else method end
-
-      html = hidden_field(object_name, hidden_field_name, value: object.send("#{method}_data").to_json, object: object, id: nil)
+      html = hidden_field(object_name, method, multiple: options[:multiple], value: object.send("#{method}_data").to_json, object: object, id: nil)
       html + file_field(object_name, method, options)
     end
   end

spec/refile/features/multiple_upload_spec.rb

@@ -0,0 +1,45 @@
+require "refile/test_app"
+
+feature "Multiple file uploads", :js do
+  scenario "Upload multiple files" do
+    visit "/multiple/posts/new"
+    fill_in "Title", with: "A cool post"
+    attach_file "Documents", [path("hello.txt"), path("world.txt")]
+    click_button "Create"
+
+    expect(download_link("Document: hello.txt")).to eq("hello")
+    expect(download_link("Document: world.txt")).to eq("world")
+  end
+
+  scenario "Fail to upload a file that is too large" do
+    visit "/multiple/posts/new"
+    fill_in "Title", with: "A cool post"
+    attach_file "Documents", [path("hello.txt"), path("large.txt")]
+    click_button "Create"
+
+    expect(page).to have_content("Documents is invalid")
+  end
+
+  scenario "Fail to upload a file that has the wrong format then submit" do
+    visit "/multiple/posts/new"
+    fill_in "Title", with: "A cool post"
+    attach_file "Documents", [path("hello.txt"), path("image.jpg")]
+    click_button "Create"
+
+    expect(page).to have_content("Documents is invalid")
+    click_button "Create"
+    expect(page).to have_selector("h1", text: "A cool post")
+    expect(page).not_to have_link("Document")
+  end
+
+  scenario "Upload files via form redisplay", js: true do
+    visit "/multiple/posts/new"
+    attach_file "Documents", [path("hello.txt"), path("world.txt")]
+    click_button "Create"
+    fill_in "Title", with: "A cool post"
+    click_button "Create"
+
+    expect(download_link("Document: hello.txt")).to eq("hello")
+    expect(download_link("Document: world.txt")).to eq("world")
+  end
+end

spec/refile/features/normal_upload_spec.rb

@@ -14,16 +14,6 @@
     expect(download_link("Document")).to eq("hello")
   end
 
-  scenario "Upload multiple files", :js do
-    visit "/multiple/posts/new"
-    fill_in "Title", with: "A cool post"
-    attach_file "Documents", [path("hello.txt"), path("world.txt")]
-    click_button "Create"
-
-    expect(download_link("Document: hello.txt")).to eq("hello")
-    expect(download_link("Document: world.txt")).to eq("world")
-  end
-
   scenario "Fail to upload a file that is too large" do
     visit "/normal/posts/new"
     fill_in "Title", with: "A cool post"

spec/refile/test_app/app/models/document.rb

@@ -1,4 +1,4 @@
 class Document < ActiveRecord::Base
   belongs_to :post
-  attachment :file
+  attachment :file, cache: :limited_cache
 end