Add Rate Limiting Support

[thinkingserious]

We would like to add support for v3 Web API rate limits, as described here.

How would you like this to be implemented? Or please give a thumbs up to express your interest in us implementing to move this task up our queue.

PRs are always welcome as well :)

[tariq1890]

@thinkingserious . I would like to help with this. But I am not sure I understand this issue completely. Isn't the rate limit already implemented for the SendGrid API? i.e. - https://api.sendgrid.com/v3/resource HTTP/1.1

Or are you looking to implement the rate-limiting logic in the sendgrid-go codebase ?

[thinkingserious]

Hi @tariq1890,

We are looking for a solution similar to this one. I hope that helps!

With Best Regards,

Elmer

[leandro-lugaresi]

This isn't a good idea! This is one kind of error that the user must handle.
In some cases, sleep and retry can be a nice way (queues?) but if this is done on a request lifetime the application must handle using another way.

[thinkingserious]

Thanks for the feedback @leandro-lugaresi.

Since we have users asking for this, I like the idea of making it optional and off by default.

I also think we should document how this could be handled by the user as you suggest here. Would you be interested in making a PR for documenting best practices? That would at least be a medium task for hacktoberfest.

With Best Regards,

Elmer

[leandro-lugaresi]

I can make this PR but first how we will handle the rate-limit?
If you want the possibility of retry automatically: We can create an option to do this (sleep+retry) and the default would return a specific error type with the information of the rate limit and the user will handle?

[tariq1890]

Yes. If I understand what Elmer said, by default we will just return a 429. The users can a use a flag if they want to sleep and retry on reaching rate limit.

[tariq1890]

@thinkingserious This requires a change in the rest repository rather than sendgrid-go

I also see that there is this issue #94 where you guys are planning on phasing the dependency out. I can continue working on this once issue #94 is closed.