Node.js 限制 API 请求并将队列限制为 1

Question

Desired Functionality

I have a node server that requests data from a third party API when the client requests data to be reloaded. I want to throttle the amount of times my node server requests reloaded data to a maximum of once every 5 minutes, regardless of which user requests the data to be reloaded.

Problem

I'm using throttled-queue at the moment, however I want to limit the queue to 1. If any additional requests are made when there is already a queue of 1, then I want that request to be disregarded.

Code

const throttledQueue = require("throttled-queue");
const throttle = throttledQueue(1, 1500);
router.get("/throttle", async (req, res, next) => {
  try {
    throttle(async function () {
      const response = await http.get();
      console.log("response in throttle test route", response.data);
      res.status(200).send({ response: response.data });
    });
  } catch (error) {
    console.log("error", error);
  }
});

How can I achieve this? Also, will throttle-queue still only call my external API call once every 5 minutes even if different users make requests?

Answer 1

I think throttle is the wrong concept for you to be using here. Really, you want to be using a cache with a 5 minute expiration time. You could use node-cache for this or any one of the various cache libraries. On cache miss you make the call to load the data and repopulate the cache.