Smarter Throttle Gate

[tanema]

related #801

This changes our rate limiter into a smart circuit breaking throttle gate. What this means functionally that:

• The request rate is limited to 4 per/second with bursts of 4 requests allowed
• When we get a 429 response, we cancel all inflight requests and they are all paused for the Retry-After value
• the allotted time is waited on
• The cancelled requests are started again
• The original request with the 429 response is restarted.
• None of these retries are counted against the http retry mechanism as they are not an error response from shopify or an error in the asset.

Todo

Tests still need to be updated a little bit.

Warn Checklist

• This changes the interface and requires a Major/Minor version change.
• I have 🎩'd these changes by using the commands I changed by hand.
• I have added a dependancy to the project.
• I have considered any potential impact on node-themekit

[andyw8]

None of these retries are not counted

Should that say "None of these retries are counted"?

[andyw8]

The request rate is limited to 4 per/second with bursts of 4 requests allowed

I think that's only for Plus, standard is 2 per second: https://shopify.dev/concepts/about-apis/rate-limits#rate-limiting-methods

[tanema]

I am referring to themekit and not shopify. Since themekit doesnt really have a way to know what the merchant is, I have set it to the larger limit, and rely on the throttling to handle it. Since the range is not the different, non-plus people will not notice the difference.