Our API servers apply FUP (Fair usage policy) which is defined in our Service level agreement. If you happen to exceed the quotas, our server will respond with an error HTTP 429 Too many requests. If you require JSON output, it is ignored and a HTML response together with the HTTP error is returned. You should be able to react to this situation and stop your API script since all further request ends up with HTTP 429. It is advisable to increase the interval between queries.
It depends on how many calls you will request, but a simple rules would be:
- if you want to do fewer than 50 requests, you don’t need to use any waiting,
- if you want to do up to 900 request, you need to use interval of 4 seconds per query,
- if you want to do more than 2000 requests, you need to use interval cca 44 seconds.
If the queries take some time, you may decrease the waiting interval.