Hyperlink to an exterior URL retrieved from database using TWIG

Question

I'm using Symfony 2.0.19. I'm trying to create a hyperlink to an external URL, which is retrieved from a database.

I tried doing this

<td><a href="{{dominio.url}}">{{dominio.url}}</a></td>

but the path I get is a relative path to the URL inside the base URL example "localhost/web/www.tralalalala.com" instead of just "www.tralalalala.com".

How do I do this?

replace `localhost/web/` whenever you have that variable `dominio.url`... and when you upload it to server, keep only the `dominio.url` and remove that replace method :D otherwise, edit .htaccess files! — Muhammad Talha Akbar, Jan 05 '13 at 06:24
if dominio.url is just www.tralalala.com you need to do `{{dominio.url}}` — Luke, Jan 05 '13 at 09:46

score 9 · Answer 1 · answered Jul 23 '16 at 12:38

Here's a concrete example of what Pierrickouw is suggesting:

Create a Twig extension or filter under src/Twig, and call it for example ExternalLinkFilter. Define the class as follows:

<?php 

namespace AppBundle\Twig;

class ExternalLinkFilter extends \Twig_Extension
{
    public function getFilters()
    {
        return array(
            new \Twig_SimpleFilter('external_link', array($this, 'externalLinkFilter')),
        );
    }

    /* source: http://stackoverflow.com/a/2762083/3924118 */
    public function externalLinkFilter($url)
    {
        if (!preg_match("~^(?:f|ht)tps?://~i", $url)) {
            $url = "http://" . $url;
        }

        return $url;
    }

    public function getName()
    {
        return 'external_link_filter';
    }
}

?>

Now, you should register this class as a service in config/services.yml as follows:

services:

    # other services

    app.twig.external_link:
        class: AppBundle\Twig\ExternalLinkFilter
        public: false
        tags:
            - { name: twig.extension }

Now you can simply use the filter called external_link as you would use any Twig's default one, e.g.:

...

<a href="{{check.hostname | external_link }}"> {{check.hostname}}</a>

...

score 3 · Accepted Answer · answered Jan 05 '13 at 10:07

3

I suggest you to build your own Twig filter.

If your url aldready have http://, don't add it, otherwise, add it.

Check here for how-tos.

answered Jan 05 '13 at 10:07

Pierrickouw

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score 0 · Answer 3 · answered May 09 '20 at 17:51

A symfony 5 version of nbro's answer will be: (This will take care of all kind of url that is read from the db)

source: https://symfony.com/doc/current/templating/twig_extension.html

in src/Twig create the file

    <?php 

    namespace App\Twig;

    use Twig\Extension\AbstractExtension;
    use Twig\TwigFilter;

    class ExternalLinkFilter extends AbstractExtension
    {
        public function getFilters()
        {
            return array(
                new TwigFilter('external_link', array($this, 'externalLinkFilter')),
            );
        }

        /* source: http://stackoverflow.com/a/2762083/3924118 */
        public function externalLinkFilter($url)
        {
            if (!preg_match("~^(?:f|ht)tps?://~i", $url)) {
                $url = "http://" . $url;
            }

            return $url;
        }

        public function getName()
        {
            return 'external_link_filter';
        }
    }

    ?>

You don't need to register it as a service. Symfony 5 will notice the presence of that Twig extension

Use it in twig template as suggested by @nbro

    <a href="{{check.hostname | external_link }}"> {{check.hostname}}</a>

Hyperlink to an exterior URL retrieved from database using TWIG

3 Answers3