discourse/app/jobs/regular/update_gravatar.rb

module Jobs

  class UpdateGravatar < Jobs::Base

    def execute(args)
      user = User.find_by(id: args[:user_id])
      avatar = UserAvatar.find_by(id: args[:avatar_id])

      if user && avatar
        avatar.update_gravatar!
        if !user.uploaded_avatar_id && avatar.gravatar_upload_id
          user.update_column(:uploaded_avatar_id, avatar.gravatar_upload_id)
        end
      end
    end
  end

end