main.mjs

import axios from 'axios';
import axiosRetry from 'axios-retry';

var foo = null;

axiosRetry(
  axios,
  {
    retries: 2,
    retryCondition: (error) => {
      return  error.response.status === 429 || axiosRetry.isNetworkOrIdempotentRequestError(error);
    },
    retryDelay: (retryCount, error) => {
      console.log("A");
      if (error.response.status === 429 && 'retry-after' in error.response.headers) {
	console.log("B");
	const retryAfter = parseInt(error.response.headers['retry-after']);
	console.log("C");
	if (typeof(retryAfter) === 'number') {
	  console.log("D");
	  return (retryAfter * 1000) + 1;
	}
      }
      console.log("DEFAULT");
      return axiosRetry.exponentialDelay(retryCount, error);
      // return retryCount * 1000;
      // return axiosRetry.exponentialDelay * 2;
    },
  },
);

try {
  const resp = await axios.get('http://localhost:8000/500');
  console.log('OK');
  console.log(resp.status);
} catch {
  console.log('NG');
}
// console.log(foo);

// on
console.log(foo);

APIはapisproutで用意した。以下はapisprouの設定。

openapi: 3.0.0
info:
  version: 1.0.0
  title: example

paths:
  "/200":
    get:
      summary: testing
      responses:
        "200":
          description: bad
          content:
            application/json:
              schema:
                type: object
                properties:
                  user_id:
                    type: string
                    example: 1234567


  "/429":
    get:
      summary: testing
      responses:
        "429":
          description: bad
          headers:
            Retry-After:
              schema:
                type: string
                example: "2"
          content:
            application/json:
              schema:
                type: object
                properties:
                  user_id:
                    type: string
                    example: 1


  "/500":
    get:
      summary: testing
      responses:
        "500":
          description: bad
          content:
            application/json:
              schema:
                type: object
                properties:
                  user_id:
                    type: string
                    example: 1234567

リクエストを確認する。

GET http://localhost:8000/429
{
  "user_id": 1
}
// GET http://localhost:8000/429
// HTTP/1.1 429 Too Many Requests
// Access-Control-Allow-Origin: *
// Content-Type: application/json
// Retry-After: 2
// Date: Tue, 07 Dec 2021 01:03:44 GMT
// Content-Length: 18
// Request duration: 0.004449s