Regex ngày chuẩn ISO yyyy-mm-dd

const re = /^\d{4}-(0[1-9]|1[0-2])-(0[1-9]|[12]\d|3[01])$/m;
const matches = str.match(re);

preg_match_all('~^\d{4}-(0[1-9]|1[0-2])-(0[1-9]|[12]\d|3[01])$~m', $str, $matches);
print_r($matches);

import re
pattern = re.compile(r"^\d{4}-(0[1-9]|1[0-2])-(0[1-9]|[12]\d|3[01])$", re.MULTILINE)
matches = pattern.findall(text)

re := regexp.MustCompile(`^\d{4}-(0[1-9]|1[0-2])-(0[1-9]|[12]\d|3[01])$`)
matches := re.FindAllString(str, -1)