使用Node.js和Promises实现指数回退

const axios = require('axios');
const { promisify } = require('util');
const sleep = promisify(setTimeout);

async function exponentialBackoff(url, maxRetries, initialDelay) {
  let retries = 0;
  let delay = initialDelay;

  while (retries < maxRetries) {
    try {
      const response = await axios.get(url);
      return response.data;
    } catch (error) {
      console.error(`Request failed: ${error.message}`);
      retries++;
      await sleep(delay);
      delay *= 2; // 指数回退，每次重试延迟时间加倍
    }
  }

  throw new Error('Exceeded maximum number of retries');
}

const url = 'https://example.com/api/data';
const maxRetries = 5;
const initialDelay = 1000; // 初始延迟时间为1秒

exponentialBackoff(url, maxRetries, initialDelay)
  .then(data => {
    console.log('Request succeeded:', data);
  })
  .catch(error => {
    console.error('Request failed after maximum retries:', error.message);
  });