Symfony 4 Pagination Service

_pagination.html.twig

{% set _currentPage = app.request.query.get('p') ?: 1 %}
{% set _currentRoute = app.request.attributes.get('_route') %}
{% set _currentParams = app.request.query.all %}
{% if lastPage > 1 %}
    <nav>
        <ul class="pagination">
            {% if _currentPage > 1 %}
                <li class="page-item">
                    <a class="page-link" href="{{ path(_currentRoute, _currentParams|merge({p: _currentPage - 1})) }}" aria-label="Previous">
                        <span aria-hidden="true">&laquo;</span>
                        <span class="sr-only">Previous</span>
                    </a>
                </li>
            {% endif %}
            {% for i in 1..lastPage %}
                <li class="page-item {% if i == _currentPage %}active{% endif %}">
                    <a class="page-link" href="{{ path(_currentRoute, _currentParams|merge({p: i})) }}">{{ i }}</a>
                </li>
            {% endfor %}
            {% if _currentPage < lastPage %}
                <li class="page-item">
                    <a class="page-link" href="{{ path(_currentRoute, _currentParams|merge({p: _currentPage + 1})) }}" aria-label="Next">
                        <span aria-hidden="true">&raquo;</span>
                        <span class="sr-only">Next</span>
                    </a>
                </li>
            {% endif %}
        </ul>
    </nav>
{% endif %}

DemoController.php

<?php

namespace App\Controller;

use App\Entity\Demo;
use App\Service\PaginationService;
use Symfony\Component\HttpFoundation\Request;

class DemoController extends AdminController
{
    const ITEMS_PER_PAGE = 50;


    public function index(Request $request, PaginationService $pagination)
    {
        $query   = $this->em->getRepository(Demo::class)->getQuery();
        $results = $pagination->paginate($query, $request, self::ITEMS_PER_PAGE);

        return $this->render('admin/school/index.html.twig', [
            'schools' => $schools,
            'lastPage' => $pagination->lastPage($results)
        ]);
    }
}

PaginationService.php

<?php

namespace App\Service;

use Doctrine\ORM\Query;
use Doctrine\ORM\QueryBuilder;
use Doctrine\ORM\Tools\Pagination\Paginator;
use Symfony\Component\HttpFoundation\Request;

class PaginationService
{
    /**
     * @param QueryBuilder|Query $query
     * @param Request $request
     * @param int $limit
     * @return Paginator
     */
    public function paginate($query, Request $request, int $limit): Paginator
    {
        $currentPage = $request->query->getInt('p') ?: 1;
        $paginator = new Paginator($query);
        $paginator
            ->getQuery()
            ->setFirstResult($limit * ($currentPage - 1))
            ->setMaxResults($limit);

        return $paginator;
    }

    /**
     * @param Paginator $paginator
     * @return int
     */
    public function lastPage(Paginator $paginator): int
    {
        return ceil($paginator->count() / $paginator->getQuery()->getMaxResults());
    }

    /**
     * @param Paginator $paginator
     * @return int
     */
    public function total(Paginator $paginator): int
    {
        return $paginator->count();
    }

    /**
     * @param Paginator $paginator
     * @return bool
     */
    public function currentPageHasNoResult(Paginator $paginator): bool
    {
        return !$paginator->getIterator()->count();
    }
}

SF4 use like this...
$query = $this->getDoctrine()->getManager()->getRepository(Demo::class)->createQueryBuilder('d');

Some improve for extrem pagination

{% set _currentPage = app.request.query.get('p') ?: 1 %}
{% set _currentRoute = app.request.attributes.get('_route') %}
{% set _currentParams = app.request.query.all %}
{% set nearbyPagesLimit = 4 %}
{% if lastPage > 1 %}
    <div class="col-md-12">
        <nav>
            <ul class="pagination">
                {% if _currentPage > 1 %}
                    <li class="page-item">
                        <a class="page-link"
                           href="{{ path(_currentRoute, _currentParams|merge({p: _currentPage - 1})) }}"
                           aria-label="Previous">
                            <span aria-hidden="true">&laquo;</span>
                            <span class="sr-only">Précedent</span>
                        </a>
                    </li>
                {% endif %}
                {% for i in 1..lastPage %}
                    {% if 0 == (_currentPage - nearbyPagesLimit) - loop.index %} {# dot before #}
                        <li class="disabled"><a class="page-link"  href="#">...</a></li>
                    {% elseif 0 == (_currentPage + nearbyPagesLimit) - loop.index %} {# dot after #}
                        <li class="disabled"><a class="page-link" href="#">...</a></li>
                    {% elseif 0 < (_currentPage - nearbyPagesLimit) - loop.index %} {# hide all before #}
                    {% elseif 0 > (_currentPage + nearbyPagesLimit) - loop.index %} {# hide all after #}
                    {% else %}
                        <li {% if _currentPage == loop.index  %} class="page-item active"{% endif %}>
                            <a class="page-link" href="{{ path(_currentRoute, _currentParams|merge({p: i})) }}">{{ loop.index }}</a>
                        </li>
                    {% endif %}
                {% endfor %}
                {% if _currentPage < lastPage %}
                    <li class="page-item">
                        <a class="page-link"
                           href="{{ path(_currentRoute, _currentParams|merge({p: _currentPage + 1})) }}"
                           aria-label="Next">
                            <span aria-hidden="true">&raquo;</span>
                            <span class="sr-only">Suivant</span>
                        </a>
                    </li>
                {% endif %}
            </ul>
        </nav>
    </div>
{% endif %}