attachments.md

Attachments Handling

This is just a quick overview of how to handle attachment mappings, searching, and highlighting.

Mappings

You can set up the FOSElasticaBundle to use attachments in the mappings. An overview of the Elasticsearch attachment plugin can be viewed here - https://github.com/elastic/elasticsearch-mapper-attachments. Installation instructions can be found on the github page. If you want to highlight content from the document, then you will need to add "store": true AND "term_vector":"with_positions_offsets" to the attachment field.

Note: Metadata mappings can be added as needed to the mappings file for attachments. More information can be seen at the Github page for Elasticsearch mapper attachments.

fos_elastica:
    indexes:
        user:
            properties:
                id: ~
                content:
                    type: attachment
                    path: full
                    fields:
                        name: { store: yes }
                        title: { store : yes }
                        date: { store : yes }
                        content : { term_vector: with_positions_offsets, store: yes }
                        ...

Attachment Searching

Here is an example query that can be ran on attachments. This also includes an example of how to use the highlights functionality for attachments.

$keywordQuery = new QueryString();
$keywordQuery->addParam(NULL, ['fuzziness' => 1]);
$keywordQuery->setQuery("$term~");
$keywordQuery->setDefaultOperator('AND');

$query = new Query($keywordQuery);
$query->setSource(["id", "..."]);
$query->setHighlight([
    'fields' => [
        'content' => new \stdClass(),
    ],
]);

Converting Attachments

This is an example of indexing documents in the required base64 encoding. You will need to specify the upload directory of all the attachments under the method getUploadDir().

public function getContent()
{
    //Upload directory set at /web/uploads/library
    return file_get_contents($this->getUploadRootDir() . '/' . $this->filename, 'r');
}

protected function getUploadRootDir()
{
    // the absolute directory path where uploaded
    // documents should be saved
    return __DIR__.'/../../../../web/'.$this->getUploadDir();
}

protected function getUploadDir()
{
    // get rid of the __DIR__ so it doesn't screw up
    // when displaying uploaded doc/image in the view.
    return 'uploads/library';
}

Handling Highlights

If you want to grab highlights from your search query, it can be achieved by implementing the HighlightableModelInterface. The interface requires the getId() and the setElasticHighlights() method. You will also need the getElasticHighlights methods to view the output. An example entity is displayed below.

use FOS\ElasticaBundle\Transformer\HighlightableModelInterface;

class Library implements HighlightableModelInterface {

    private $id

    private $highlights;

    //Needs this method for HighlightableModelInterface
    public function getId()
    {
        return $this->id;
    }

    //Needs this method for HighlightableModelInterface
    public function setElasticHighlights(array $highlights)
    {
        $this->highlights = $highlights;

        return $this;
    }

    public function getElasticHighlights()
    {
        return $this->highlights;
    }

}

Viewing Highlights in Twig

This is just a quick reference to obtaining the highlighted text returned by the query in a TWIG file.

{% for highlights in reference.ElasticHighlights %}
    {% for highlight in highlights %}
        <tr class="alert alert-info">
            <td></td>
            <td></td>
            <td>{{ highlight|raw }}</td>
        </tr>
    {% endfor %}
{% endfor %}