dwyl/learn-elixir

Timers (or how to do `setInterval` and `clearInterval` in `Elixir` / `Erlang`?)

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#225 opened on Jan 3, 2025

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 (3 comments) (0 reactions) (1 assignee)Elixir (1,695 stars) (113 forks)batch import
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Description

I'm making a few million API requests to get some data https://github.com/dwyl/who/issues/17 and need to control the request frequency to avoid hitting rate limits ... ⏳ (5k/hour -> 120k/day -> 3.65m/month ) In JS-land I would just use setInterval to define the timeframe for executing the API requests and clearInterval once they were complete. Not had to do this in Elixir before, so doing a bit of googling ... 🔍

Reading: https://stackoverflow.com/questions/43892784/what-are-the-equivalent-of-settimeout-and-setinterval-in-elixir

image

The recommended Erlang function is: timer.apply_interval/4

:timer.apply_interval(1000, IO, :puts, ["weee"])

https://www.erlang.org/doc/apps/stdlib/timer.html

Need to write myself a mini example ...

Side note: notice how this question on StackOverflow that has clearly been useful to other people got 4 downvotes: stackoverflow-downvotes-on-questions yes, it doesn't conform to the narrow SO question guidelines, but it's still a useful question/answer! SO is just not a very welcoming (to beginners) environment. 😞 This in a nutshell is why ChatGPT which just repackages the web is so popular: it doesn't "judge" your ("stupid") questions!

Contributor guide

Tech stack
elixir
Domain
documentation
Issue type
research
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
fresh
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
clear
Prerequisites
Elixir basicsErlang/OTP
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
60
Research direction
This issue documents how to implement setInterval/clearInterval in Elixir using Erlang's :timer.apply interval/4. The investigation can be expanded by adding a dedicated guide to the repository covering rate limiting with timers. Refer to the linked issue in dwyl/who for context, and consider the assignee's ongoing work.