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I use Symfony2 to build a website that will request data from a web service. Requests are made from the server (not the client). I would like to use a cache mechanism to store the responses received from the web service, so that I do not issue the same request again and again.
Is there an API in Symfony core to manage files in cache ? I would like to use the /app/cache directory but cannot find the best way to do this. I could write files directly into this directory, but then I will not benefit from the automatic environment management.
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Doctrine cache can be a solution for you as mentioned in comment of your question.
But for this kind of needs HTTP caching seems better, you can use symfony2 built-in reverse proxy or a soft like varnish
Symfony2 related documentation : http://symfony.com/doc/current/book/http_cache.html
Tutorial for nginx + varnish + wordpress ( just as an exemple ) : https://www.digitalocean.com/community/articles/how-to-install-wordpress-nginx-php-and-varnish-on-ubuntu-12-04