CA
Crawlee & Apify•3y ago
rival-black

How do I delay requests with HttpCrawler?

I am working with an API that has rate-limiting in place. The API gives me a timestamp of when the current rate limit will expire in seconds. I need to delay my next request by this many seconds, which is usually 15 ish minutes. I tried adding a delay with setTimeout and Promise like this and awaiting on it 
export function delay(seconds: number): Promise<void> {
    return new Promise((resolve) => setTimeout(resolve, seconds * 1000))
}
export function delay(seconds: number): Promise<void> {
    return new Promise((resolve) => setTimeout(resolve, seconds * 1000))
}
(this delay happens inside my requestHandler) But when it finishes I get this error on next request RequestError: read ECONNRESET I am not well-versed with networking, but I think this error is related to it. My understanding is that Crawlee tries to use the same connection that it opened ~15 minutes ago but that connection is closed from the API's side, thus this error. Any help or suggestions on how to achieve this would be appreciated!
5 Replies
extended-salmon
extended-salmon•3y ago
rival-black
rival-blackOP•3y ago
Can you elaborate more on how to do this please? thanks! I mean the adding the delay to router part, I looked at the documentation and couldn't find a way to do it.
like-gold
like-gold•3y ago
other-emerald
other-emerald•3y ago
1. How do they recognize that you are the one doing the same request? Is it authenticated or IP address based? 2. I would simply set maxConcurrency to 1, timeout to 999999 and sleep for the amount in the requestHandler and then enqueue the next request
rival-black
rival-blackOP•3y ago
Sorry for the late response, 1. Yes authenticated using a bearer token 2. This was exactly my initial solution and also what led me to discover the ECONNRESET error when the requestHandler waited for more than ~15 minutes I ended up using BasicCrawler and Axios to make requests and that seems to have fixed the problem.

Did you find this page helpful?