location_filter.php

<?php

/*
// createLocationFilter generates the location filter based on the
// location matching matrix provided by careerone
func createLocationFilter(locationLevel int, locations []int) string {
	filterSegmentFmt := "(location_level_%[1]d = %[2]d OR location_level_%[1]d = 0)"
	s := make([]string, 0, len(locations))

	for i := locationLevel; i < len(locations)+1; i++ {
		s = append(s, fmt.Sprintf(filterSegmentFmt, i, locations[i-1]))
	}

	return strings.Join(s, " AND ")
}
*/

function createLocationFilter($job_location_level, $location_level_values) {
    $filter_segment_fmt = "(location_level_%[1]d = %[2]d OR location_level_%[1]d = 0)";
    $filter_segments = [];

    // start filter creation from job location search
    for ($i=$job_location_level; $i < count($location_level_values); $i++) {
        array_push($filter_segments, sprintf($filter_segment_fmt, $i, $location_level_values[$i-1]));
    };

    return implode(" AND ", $filter_segments);
}


/*
func createFilterBoostFilters(locationLevel int) map[string]string {
	s := make([]string, 0, 5)
	for i := 1; i <= 5; i++ {
		if i < locationLevel {
			continue
		}
		if i == locationLevel {
			s = append(s, fmt.Sprintf("job_location_level <= %d", locationLevel))
			continue
		}
		s = append(s, fmt.Sprintf("job_location_level = %d", i))
	}

	m := make(map[string]string, 5)
	for i, f := range s {
		m[fmt.Sprintf("location_level_boost_%d", i+1)] = f
	}
	return m
}
*/

function createFilterBoostFilters($job_location_level) {
    $tmp = [];
    for ($i = 0; $i <= 5; $i++) {
        if ($i < $job_location_level) {
            continue;
        }
        if ($i == $job_location_level) {
            array_push($tmp, sprintf("job_location_level <= %d", $job_location_level));
            continue;
        }
        array_push($tmp, sprintf("job_location_level = %d", $i));
    }

    $filters = [];
    foreach ($tmp as $i => $filter) {
        $filters[sprintf("location_level_boost_%d", $i)] = $filter;
    }
    return $filters;
}

?>

query.php

<?php
$location_level = 2;
$location_query = [0, 15216, 15279, 15295, 15299];
$location_filter = createLocationFilter($location_level, $location_query);

$values = [
    "q" => "", // replace with the query string
    "filter" => sprintf("(bucket_code = 'ORGANIC' OR bucket_code ='PRIORITISE') AND (%s)", $location_filter),
];
$response = $pipeline->search(array_merge($values, createFilterBoostFilters($location_level)));
?>