Rsa97

function genWords($alphabet, $length) {
    $alph = mb_str_split($alphabet);
    $maxChar = count($alph);
    $idxs = array_fill(0, $length, 0);
    while (true) {
        yield implode('', array_map(fn($idx) => $alph[$idx], $idxs));
        $pos = $length - 1;
        while (true) {
            $idxs[$pos] += 1;
            if ($idxs[$pos] < $maxChar) {
                break;
            }
            $idxs[$pos] = 0;
            $pos -= 1;
            if ($pos < 0) {
                return;
            }
        }
    }
}

foreach (genWords('АБВГДЕЁЖЗ', 5) as $word) {
    print "{$word}\n";
}

$ man ssh-copy-id
...
-i identity_file
             Use only the key(s) contained in identity_file (rather than looking for identities via ssh-add(1)
             or in the default_ID_file).  If the filename does not end in .pub this is added.  If the filename
             is omitted, the default_ID_file is used.
...

const data = new FormData();
data.append('grant_type',  ...);
data.append('client_id', ...);
data.append('client_secret', ...);

const response = await fetch(
  url,
  {
    method: 'POST',
    body: data
  }
);

const token = await response.json();