Extract markdown field to gem

Gemfile

@@ -55,6 +55,7 @@ end
 gem 'administrate'
 gem 'administrate-field-image'
 gem 'administrate-field-color'
+gem 'administrate-field-markdown'
 gem 'dragonfly'
 gem 'dragonfly-s3_data_store'
 gem 'kaminari'

Gemfile.lock

@@ -54,6 +54,10 @@ GEM
     administrate-field-image (0.0.2)
       administrate (>= 0.2.0.rc1, < 0.3.0)
       rails (~> 4.2)
+    administrate-field-markdown (0.0.2)
+      administrate (>= 0.2.0.rc1, < 0.3.0)
+      kramdown (~> 1.10)
+      rails (~> 4.2)
     arel (6.0.3)
     ast (2.2.0)
     autoprefixer-rails (6.3.6)
@@ -324,6 +328,7 @@ DEPENDENCIES
   administrate
   administrate-field-color
   administrate-field-image
+  administrate-field-markdown
   aws-sdk
   better_errors
   binding_of_caller

app/dashboards/page_dashboard.rb

@@ -11,7 +11,7 @@ class PageDashboard < Administrate::BaseDashboard
     id: Field::Number,
     name: Field::String,
     title: Field::String,
-    content: MarkdownField,
+    content: Field::Markdown,
     created_at: Field::DateTime,
     updated_at: Field::DateTime,
   }

app/dashboards/photo_dashboard.rb

@@ -14,7 +14,7 @@ class PhotoDashboard < Administrate::BaseDashboard
     created_at: Field::DateTime,
     updated_at: Field::DateTime,
     title: Field::String,
-    description: MarkdownField,
+    description: Field::Markdown,
     sort: Field::Number,
     featured: Field::Boolean,
     enabled: Field::Boolean,

app/fields/markdown_field.rb

@@ -1,21 +0,0 @@
-require "administrate/field/base"
-
-class MarkdownField < Administrate::Field::Base
-  def to_s
-    data
-  end
-
-  def rendered
-    Kramdown::Document.new(data).to_html.html_safe
-  end
-
-  def truncate
-    data.to_s[0...truncation_length]
-  end
-
-  private
-
-  def truncation_length
-    options.fetch(:truncate, 50)
-  end
-end

app/views/fields/markdown_field/_form.html.erb

@@ -1,6 +0,0 @@
-<div class="field-unit__label">
-  <%= f.label field.attribute %>
-</div>
-<div class="field-unit__field">
-  <%= f.text_area field.attribute %>
-</div>

app/views/fields/markdown_field/_index.html.erb

@@ -1 +0,0 @@
-<%= field.truncate %>

app/views/fields/markdown_field/_show.html.erb

@@ -1 +0,0 @@
-<%= field.rendered %>