learning-jsdp/ch09/async_retry.html at main · addyosmani/learning-jsdp · GitHub

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<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Retrying an Async Operation on Failure</title>
  <style>
    button {
      margin-top: 10px;
    }
    pre {
      background-color: #f7f7f7;
      padding: 10px;
    }
  </style>
</head>
<body>
  <h1>Retrying an Async Operation on Failure</h1>
  <button id="retryButton">Retry</button>
  <pre id="output"></pre>

  <script>
    async function makeRequest(url) {
      try {
        const response = await fetch(url);
        const data = await response.json();
        return data;
      } catch (error) {
        throw error;
      }
    }

    async function retry(fn, maxRetries = 3, retryDelay = 1000) {
      let retries = 0;

      while (retries <= maxRetries) {
        try {
          return await fn();
        } catch (error) {
          retries++;
          console.error(error);
          await new Promise(resolve => setTimeout(resolve, retryDelay));
        }
      }

      throw new Error(`Failed after ${retries} retries.`);
    }

    const retryButton = document.getElementById('retryButton');
    const output = document.getElementById('output');

    retryButton.addEventListener('click', async () => {
      output.innerText = '';

      try {
        const data = await retry(() => makeRequest('https://jsonplaceholder.typicode.com/posts/1'));
        output.innerText = JSON.stringify(data, null, 2);
      } catch (error) {
        output.innerText = `Error: ${error.message}`;
      }
    });
  </script>
</body>
</html>