How to call an api and stay inside the rate limit (react javascript)

Question

I am attempting to use the riot-api to build statistics pages for different players. The algorithm works after a specific player is identified, then an api call will attempt to fetch about 15 games. I then want to iterate through this list of 15 games where for each game, I need to make another api call to pull that matches specific game data. The game data then gets saved to cloud firestore. I choose to get about 15 games at a time because the riot api limits to 20 calls a second, and 100 calls every 2 minutes. The issues is I am going through all the algorithm too fast and I am getting a 429 error because I am hitting the limit. Is there a way to slow down the rate of my api calls to stay in the window or is there a better way to deal with the 429 error like a retry?

Answer 1

You can use Cloud Tasks for rate limiting your calls to the riot-api. There are a couple of ways to achieve this...

1. Create a Callable Function (in Firebase) and use this to write your requests, then have the function add them to a Cloud Tasks HTTP queue with a rate limit.
2. Write the data to Cloud Firestore/ RTDB, which triggers a Cloud Function to add the request(s) to a Cloud Tasks HTTP queue with a rate limit.

Create another HTTP Cloud Function (the worker) to receive tasks from the queue, call the riot-api and write the data to Cloud Firestore. If you receive an error from the riot-api, the task will retry. Cloud Tasks will automatically reduce the rate of retries to avoid overloading your endpoint.