03-integration.md

Integration

There are various ways to integrate SolrQueryComponent with your custom query facades. The following examples will assume some kind of a SearchService, that acts as a Facade to access the Solr search index.

We start with a simple base class for search services in general that define methods to create an instance of ExpressionBuilder and new instances of QueryString. We assume further, that we use http://pecl.php.net/package/solr as a client.

<?php
namespace Acme\Search;

// SolrQueryComponent classes
use InterNations\Component\Solr\Expression\ExpressionBuilder;
use InterNations\Component\Solr\Query\QueryString;
// PECL Solr classes
use SolrClient;
use SolrQuery;

abstract class AbstractSearchService
{
    private $expressionBuilder;

    protected $client;

    public function __construct(SolrClient $client)
    {
        $this->client = $client;
    }

    protected function createQuery()
    {
        return new SolrQuery();
    }

    protected function createExpressionBuilder()
    {
        // Expression builder is stateless, so we can reuse the same instance over and over again
        if (!$this->expressionBuilder) {
            $this->expressionBuilder = new ExpressionBuilder();
        }
        return new $this->expressionBuilder;
    }

    protected function createQueryString($query)
    {
        return new QueryString($query);
    }
}

A concrete search service will extend the abstract base class and add index specific search methods.

<?php
namespace Acme\Search;

class CatalogSearchService extends AbstractSearchService
{
    public function searchByName($searchString, $rows, $start = 0)
    {
        $searchQuery = $this->createQueryString('productName:<name>')
            ->setPlaceholder('name', $searchString);

        $eb = $this->createExpressionBuilder();
        $filterQuery = $eb->req($eb->comp($eb->field('disabled', 0)), $eb->field('visible', 1));

        $query = $this->createQuery()
            ->setQuery($searchQuery)
            ->addFilterQuery($filterQuery)
            ->setStart($start)
            ->setRows($rows);

        return $this->client->query($query);
    }
}

Whether you prefer the expression builder or the query string API is a matter of taste. Generally, simple queries are easier to read (and write) with the query string API, more complex queries, dynamically build upon user input, are easier to construct with the expression builder API.