Filter results with sets via URL

functions.php

<?php 

// ..

// filetrs for form ID: 1
add_filter('gfexcel_output_search_criteria_1', function ($search) {
    // Add a group with filters
    // An operator can be: <, >, =, >=, <=, <>, contains, like, is, is not, in, not in
    $filters['groupA'] = [
        // mode says: <mode> of the following rules should apply for me to filter
        'mode' => 'any',
        // or 'all'. 'all' is default, and then this can be omitted.
        // [Field id, operator, value]
        ['1', 'contains', 'Onion'],
        // a single field with a value containing "Onion"
        ['2.4', 'contains', 'Peanut'],
        // A multipart field (like name or address) (2) where the subfield (4) contains "Peanut"
    ];

    // Retrieve the filterset from the url (?subset=<filfter-group>)
    $subset = rgar($filters, rgar($_GET, 'subset'), []);
    if (!$subset) {
        // none found, so no filtering.
        return $search;
    }

    // remap the filters so it's following the rules.
    $field_filters = rgar($search, 'field_filters', []);
    $search['field_filters'] = array_merge($field_filters, array_map(function ($row) {
        if (!is_array($row)) {
            return $row;
        }

        list($key, $operator, $value) = $row;
        return compact('key', 'operator', 'value');
    }, $subset));

    return $search;
});

@websherpa Is this something you can work with?

It's not as nice as I would like it to be, but I can't seem to find the time to do it less verbose without introducing some new files.