Gab Social. All are welcome.

app/models/preview_card.rb

@@ -0,0 +1,86 @@
+# frozen_string_literal: true
+# == Schema Information
+#
+# Table name: preview_cards
+#
+#  id                 :bigint(8)        not null, primary key
+#  url                :string           default(""), not null
+#  title              :string           default(""), not null
+#  description        :string           default(""), not null
+#  image_file_name    :string
+#  image_content_type :string
+#  image_file_size    :integer
+#  image_updated_at   :datetime
+#  type               :integer          default("link"), not null
+#  html               :text             default(""), not null
+#  author_name        :string           default(""), not null
+#  author_url         :string           default(""), not null
+#  provider_name      :string           default(""), not null
+#  provider_url       :string           default(""), not null
+#  width              :integer          default(0), not null
+#  height             :integer          default(0), not null
+#  created_at         :datetime         not null
+#  updated_at         :datetime         not null
+#  embed_url          :string           default(""), not null
+#
+
+class PreviewCard < ApplicationRecord
+  IMAGE_MIME_TYPES = ['image/jpeg', 'image/png', 'image/gif', 'image/webp'].freeze
+  LIMIT = 1.megabytes
+
+  self.inheritance_column = false
+
+  enum type: [:link, :photo, :video, :rich]
+
+  has_and_belongs_to_many :statuses
+
+  has_attached_file :image, styles: ->(f) { image_styles(f) }, convert_options: { all: '-quality 80 -strip' }
+
+  include Attachmentable
+
+  validates :url, presence: true, uniqueness: true
+  validates_attachment_content_type :image, content_type: IMAGE_MIME_TYPES
+  validates_attachment_size :image, less_than: LIMIT
+  remotable_attachment :image, LIMIT
+
+  before_save :extract_dimensions, if: :link?
+
+  def save_with_optional_image!
+    save!
+  rescue ActiveRecord::RecordInvalid
+    self.image = nil
+    save!
+  end
+
+  class << self
+    private
+
+    def image_styles(f)
+      styles = {
+        original: {
+          geometry: '400x400>',
+          file_geometry_parser: FastGeometryParser,
+          convert_options: '-coalesce -strip',
+        },
+      }
+
+      styles[:original][:format] = 'jpg' if f.instance.image_content_type == 'image/gif'
+      styles
+    end
+  end
+
+  private
+
+  def extract_dimensions
+    file = image.queued_for_write[:original]
+
+    return if file.nil?
+
+    width, height = FastImage.size(file.path)
+
+    return nil if width.nil?
+
+    self.width  = width
+    self.height = height
+  end
+end