Calling API's every x seconds

JavaScript
1

I want to call API’s every x second and this is what i have so far and was hoping suggestions of critique could help me out a lot.

function sendApiRequest() {
  
  fetchData(); // this function will make API calls and inside this is a call for function that 
                        //processes the data
  console.log("Sending API request at " + new Date());
}

// Set the interval (in milliseconds) for sending API requests
const interval = 30000; // 30000 milliseconds = 30 seconds

// Set up the interval to call the function
//const intervalId = setInterval(sendApiRequest, interval);
setInterval(sendApiRequest, interval);

Also on some online sources i noticed that setInveral() call is assigned to a variable?

Please let me know what you think.

2

It depends on the context, but I did choose to move similar tasks to a separate server. A cron server. The main reason for a separate server is to reduce the load on the web server.

FWIW

3

This is only important if you want to cancel the timer. E.g.:

// Set an interval to log a message every second
const intervalId = setInterval(() => {
  console.log("Hello, World!");
}, 1000);

// Set a timeout to cancel the interval after 5 seconds
setTimeout(() => {
  clearInterval(intervalId);
  console.log("Interval has been cleared.");
}, 5000);

This will output:

Hello, World!
Hello, World!
Hello, World!
Hello, World!
Interval has been cleared.

If you don’t intend to clear the timer, you don’t need to worry about assigning it to a variable.

1 Like
4

I don’t intend to cancel the interval. My goal is when user lands up on the page to be
shown fresh status of call center agent being offline and online. I guess it will get cancelled once the user closes the page.

5

Hi @Stribor45, one suggestion would be to schedule the next request only after the previous one is completed; this way you’ll avoid race conditions if one request takes longer than the given interval. E.g., assuming fetchData() returns a promise:

const interval = 30000

function sendApiRequest() {
  fetchData().finally(() => {
    setTimeout(sendApiRequest, interval)
  })
}

sendApiRequest()

Yup. :-)

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