Allow longer pod names for k8s executor / KPO

[dstandish]

Previously this limited pod length to 63 but that's the limit for label values not pod ids.

Meanwhile, a UUID was previously used which occupies 32 characters, much more space than necessary. This left you with a short and not very readable pod name.

Here we update the logic to use a suffix of 8 random alphanum chars, and set a longer max length of 80 characters.

One qualification on that. We set a max length of 80 when we control the pod name -- e.g. when using kube executor or KPO when pod name not supplied. Since we're generating it, 80 is a reasonable max. But, with KPO, when pod_id, and user asks for random suffix, we set max length to 253, to give user most control.

Along the way, we consolidate the name building logic into one function. Previously, one function would create the "pod_id" and then, only later in the process would a random suffix be added. Here, all of that is done in create_pod_id, and its behavior is controllable with params. cc @o-nikolas

Why 80 characters: that's about as much as can reasonably fit on a normal-sized terminal. Any more doesn't help with readability.

Why 8 character suffix: 8 random characters is more than enough. Probably fewer would be fine too.

Finally, a note.... I copied the core code to provider and we must keep it there until min airflow version catches up. And instead of duplicating test code, i parameterized the core test to also handle provider.

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Now, an example.

Calling with

PodGenerator.make_unique_pod_id("this-is-my-semi-long-but-not-too-long-pod-id")

We would previously get this:

this-is-my-semi-long-but-not-t-c27ae4725b2049d6bf953e9f1f3d14c1

And now we'd get this:

this-is-my-semi-long-but-not-too-long-pod-id-l4hiiqxh

[potiuk]

Errors