code: function mkcert(appDataPath, exe) {
    const logPath = path.join(appDataPath, "mkcert.log")
    const errPath = path.join(appDataPath, "mkcert.err")
    // escape spaces in appDataPath (Mac OS)
    appDataPath = appDataPath.replace(" ", "\\ ")
    const exePath = path.join(appDataPath, exe)
    const crtPath = path.join(appDataPath, "localhost.crt")
    const keyPath = path.join(appDataPath, "localhost.key")
    const cmd = exePath + " -install -cert-file " + crtPath +
      " -key-file " + keyPath + " localhost"
    return new Promise((resolve, reject) => {
      console.log("Running mkcert to generate certificates...")
      exec(cmd, (err, stdout, stderr) => {
        // log
        const errFun = err => {
          /* istanbul ignore if: cannot be tested */
          if (err) console.error(err)
        }
        fs.writeFile(logPath, stdout, errFun)
        fs.writeFile(errPath, stderr, errFun)
        /* istanbul ignore if: cannot be tested */
        if (err) reject(err)
        resolve()
      })
    })
  }
docs: execute the binary executable to generate the certificates