Check Passwords Against BreechList Fast

Breech_Checker.js

import sha1 from "sha1";
import axios from "axios";

const BREECH_TOLERENCE = 100;
isBreeched = password => {
  const pwSha1 = sha1(password).toUpperCase();
  const salt = pwSha1.slice(0, 5);
  const pepper = pwSha1.slice(5);
  return axios
    .get(`https://api.pwnedpasswords.com/range/${salt}`)
    .then(response => {
      const hashes = response.data;
      var re = new RegExp(`${pepper}\\:(\\d*)`, "gm");
      const regArr = re.exec(hashes);
      console.log(regArr);
      if (regArr && regArr.length > 0) {
        const freq = parseInt(regArr[1], 10);
        if (freq > BREECH_TOLERENCE) return true;
      }
      return false;
    })
    .catch(err => {
      // we don't want a bad connection to breech list ruin or reg
      console.error(
        "Unable to check breech list for password. Please be sure to use a strong and secure password.",
        err
      );
      return true;
    });
};