Implement an asyncAuth function with a callback interface that returns a Promise. Then implement a tryAuth(n) function that uses asyncAuth and makes n additional attempts in case of failure. If all attempts fail, it returns the last error.

Here is an example implementation of the asyncAuth function with a callback interface that returns a Promise, and the tryAuth(n) function that retries on error:

// asyncAuth accepts a callback with (error, result)
function asyncAuth(callback) {
  return new Promise((resolve, reject) => {
    // Simulate asynchronous authorization
    setTimeout(() => {
      const success = Math.random() > 0.5; // 50% chance of success
      if (success) {
        callback(null, "Authorization successful");
        resolve("Authorization successful");
      } else {
        const err = new Error("Authorization error");
        callback(err);
        reject(err);
      }
    }, 100);
  });
}

async function tryAuth(n) {
  let lastError = null;
  for (let i = 0; i <= n; i++) {
    try {
      const result = await asyncAuth((err, res) => {
        // callback can be used for logging or other purposes
        if (err) console.log(`Attempt ${i + 1}: error`);
        else console.log(`Attempt ${i + 1}: success`);
      });
      return result; // Successful authorization
    } catch (err) {
      lastError = err;
    }
  }
  throw lastError; // All attempts failed
}

// Usage example
tryAuth(3)
  .then(res => console.log("Result:", res))
  .catch(err => console.error("Error after all attempts:", err.message));

In this code:

• asyncAuth simulates an asynchronous operation with a callback and returns a Promise.
• tryAuth(n) attempts to call asyncAuth up to n+1 times (the first attempt + n retries).
• If all attempts fail, the last error is thrown.
• Inside the callback, you can handle intermediate results or errors.