Call Fastly API sequentially

[Jakeii]

What does this change?

Instead of updating both dictionaries in parallel, update them sequentially with a small delay.

Why?

There's been a few reports now of opt in and out links 404ing, I've traced the issue to an issue with edge dictionary updates reflecting in fastly's VCL.

The edge dictionaries are updated successfully according to the API and the GUI. But it isn't reflected in the VCL.

I suspect this could be a bug in Fastly's API with updating multiple dictionaries simultaneously. Fastly reccomend avoiding concurrent requests! See below

To confirm/mitigate, I suspect giving a few milliseconds between the API calls will help.

There's also a note on this docs page about avoiding concurrent updates https://www.fastly.com/documentation/reference/api/#rate-limiting

IMPORTANT: Overlapping write requests to the API may result in lost updates. We strongly recommend avoiding concurrent requests that modify configuration within the same service.

Screenshots

The Dictionary GUI is always updated with changes as expected

But this is not always reflecting in the "Complete VCL"

table gu_ab_test_groups {
    "commercial-prebid-v10:control": "exp=1773100800,type=client",
    "commercial-prebid-v10:variant": "exp=1773100800,type=client",
    "commercial-user-module-liveramp:control": "exp=1769731200,type=client",
    "commercial-user-module-liveramp:variant": "exp=1769731200,type=client",
    "commercial-user-module-uid2:control": "exp=1768435200,type=client",
    "commercial-user-module-uid2:variant": "exp=1768435200,type=client",
}

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[github-actions]

Deploy build 455 of dotcom:ab-testing to CODE

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