Pass a context to every kopf call/handler

[kopf-archiver]

An issue by krish7919 at 2020-04-12 12:34:48+00:00
Original URL: zalando-incubator/kopf#347
 

Question

I would like to embed kopf in an application to perform some extra cluster functions as a response to events.

I can always use a global variable.
Actually, I have to go the embedding way as I want to build wrappers to take some custom arguments as input, validate them, form connection strings, and then start the kopf asyncio loop. Plus I have to pass these params around as every handler would need them.

This should be a pretty common ask, and I am not sure how is that done currently.

Checklist

• I have read the documentation and searched there for the problem

• I have searched in the GitHub Issues for similar questions

Keywords

"kopf pass context to handlers" on Google and in docs.

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Commented by nolar at 2020-04-15 21:17:39+00:00
 

krish7919 Just to clarify: do you mean an arbitrary object of arbitrary class, which is passed through the call stack from the owning application down to the handlers (all of them), right? Something like a memo kwarg (per-resource container for arbitrary keys/fields), but global and of external origin?

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Commented by krish7919 at 2020-04-15 21:33:47+00:00
 

Precisely. In Go, this is the context, or a struct with the values required.

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Commented by mnaser at 2020-04-17 21:05:10+00:00
 

This is something that's interesting for our usage too, especially when we're constantly trying to connect to the Kuberentes API..

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Commented by eshepelyuk at 2020-05-17 03:16:03+00:00
 

This issue also may be related to my question in #367

[nolar]

Pre-released in kopf>=1.30.0rc1, docs: https://kopf.readthedocs.io/en/latest/memos/

Includes cross-handler data exchange (incl. cross-resource-&-operator-handlers) and arbitrary structs for embedded operators.

FYI, @krish7919, @mnaser.