Sort merged array by array value in Twig?

Question

I have two Instagram API responses that I want to merge, by the photo's created_time. Is there a way to do that in Twig?

Right now I am just using this

{% set instagram = <data> %}
{% set community = <data> %}
{% set feed = instagram|merge(community) %}

    {% for photo in feed %}
        <img src="{{photo.images.low_resolution.url}}" alt="">
        <br />
    {% endfor %}

Each photo has a created_time string that I'd like to sort the array by, is that possible without creating a custom Twig extension?

The sortByField plugin looked promising and sort of what I want, but it was directly aimed at Craft entry manipulation. Is there anything hacky that could be done?

Answer 1

This is only possible with a custom Twig Extension, since sorting a multidimensional array can't be done with Twig itself.

I've written a plugin which extends Twigs sorting methods, which you could use as a base: Craft-TwigBetterSort.

Just add this to the TwigBetterSortTwigExtension.php

public function twig_sort($array, $method='asort', $sort_flag='SORT_REGULAR')
{
    // ....
    case 'custom_sort_name':
        usort($array, array('TwigBetterSortTwigExtension','custom_sort_function'));
        break;
    // ....
}

private function custom_sort_function($a, $b)
{
    // Do stuff with your array
}

and use it like this in your templates:

{% array|sort('custom_sort_name') %}

Answer 2

The SuperSort Plugin is built for use cases exactly such as this. It allows you to render each object in your array using a Twig object template and sort the array based on the rendered value.

For example, in OP's case, we could sort the combined array by the created_time variable like this:

...
{% set feed = instagram|merge(community) %}
{% set sortedFeed = feed | supersort('sortAs', '{created_time}') %}

(The plugin parses {created_time} — a Craft 'micro-template' — into {{object.created_time}}, which provides the value by which the array is sorted.)

If the property of interest happened to be different between two arrays, we could include a conditional or ternary operator in the micro-template to differentiate them:

{% set sortedFeed = feed | supersort('sortAs', '{{ object.current_time is defined ?: object.someOtherProperty }}') %}