Bootstrap 4 will paginate

paginate_helper.rb

module PaginateHelper
  class BootstrapRenderer < WillPaginate::ActionView::LinkRenderer
    def prepare collection, options, template
      options[:params] ||= Hash.new
      options[:params]['_'] = nil

      super(collection, options, template)
    end

    protected
    def html_container html
      tag(:nav, tag(:ul, html, class: 'pagination'))
    end

    def previous_or_next_page page, text, classname
      classname = [classname, 'page-link'].compact.join(' ')

      if page
        link(text, page, class: classname)
      else
        tag(:li, tag(:a, text, class: classname), class: 'disabled page-item')
      end
    end

    def page_number page
      unless page == current_page
        tag(:li, link(page, page, rel: rel_value(page)), class: 'page-item')
      else
        tag(:li, tag(:a, page, class: 'page-link'), class: 'page-item active')
      end
    end

    def link text, target, **attributes
      if target.is_a? Fixnum
        attributes[:rel] = rel_value(target)
        target = url(target)
      end

      attributes[:class] = [attributes[:class], 'page-link'].compact.join(' ')

      tag(:li, @template.link_to(text.to_s.html_safe, target, attributes), class: 'page-item')
    end

    def gap
      tag(:li, tag(:a, '...', class: 'page-link'), class: 'page-item')
    end
  end

  # Optional helper to use Bootstrap pagination
  def bootstrap_will_paginate collection, **options
    will_paginate(collection, options.merge(renderer: PaginateHelper::BootstrapRenderer))
  end
end