$re = '/(?<=\"attributes\":) (\{(?:(?:[^{]*?\{(?:[^{]|\n)*?\}[^{]*?)+|(?:[^{]|\n)*?)})/m';
$str = '{"items_game": {
"prefabs": {
...
"coupon_crate_prefab": {
"prefab": "weapon_case_base",
"item_type": "coupon_crate",
"attributes": {
"cannot trade": "1"
},
"capabilities": {
"can_delete": "0"
},
"attributes": {
"expiration date": {
"attribute_class": "expiration_date",
"force_gc_to_generate": "1",
"use_custom_logic": "expiration_period_days_from_now",
"value": "2"
}
}
}
...
}
}';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php