How to create a macro that convert bytes to KB, MB, GB etc

Question

I have a video in my page and we can download it, next to the download link I have a number that shows the size of the video.

Now I have it in bytes, and I want to convert it in KB, MB or GB. From what I understood the best way of doing that is with a macro.

{% macro downloadSize(bytes) %}
{% spaceless %}
     {% set bytes = x/1024 %}

     {% if bytes < 1024 %}
       KB
     {% endif %}
     ...    
{% endspaceless %}
{% endmacro %}

I know I dont have much, but I really need help on the syntax and how to acomplish this. I want my final value to be like " 12.2 MB "

Answer 1

As @Flukey mentioned, the way is to create an extension.

I've done that as an exercise. Just go to

https://github.com/BrazilianFriendsOfSymfony/BFOSTwigExtensionsBundle

and get the extension.

Answer 2

And old question, but for anyone else -> if for any reason you don't want to meddle with TwigExtensions here is how that macro would look like:

{% macro bytesToSize(bytes) %}
{% spaceless %}
    {% set kilobyte = 1000 %}
    {% set megabyte = kilobyte * 1000 %}
    {% set gigabyte = megabyte * 1000 %}
    {% set terabyte = gigabyte * 1000 %}
    {% set petabyte = terabyte * 1000 %}

    {% if bytes < kilobyte %}
        {{ bytes ~ ' B' }}
    {% elseif bytes < megabyte %}
        {{ (bytes / kilobyte)|number_format(2, '.') ~ ' KB' }}
    {% elseif bytes < gigabyte %}
        {{ (bytes / megabyte)|number_format(2, '.') ~ ' MB' }}
    {% elseif bytes < terabyte %}
        {{ (bytes / gigabyte)|number_format(2, '.') ~ ' GB' }}
    {% elseif bytes < petabyte %}
        {{ (bytes / terabyte)|number_format(2, '.') ~ ' TB' }}
    {% else %}
        {{ (bytes / petabyte)|number_format(2, '.') ~ ' PB' }}
    {% endif %}
{% endspaceless %}
{% endmacro %}

EDIT: modified the script to match decimal measurement (KB, MB, GB..) instead of binary (KiB, MiB, GiB...).