Fix deleting instances with replicant attribute set

[ismirlia]

When the pi_replicant field is set in terraform it creates a bunch of vms as expected, but terraform destroy does not delete these.

This fixes: #5168

--- PASS: TestAccIBMPIInstanceBasic (680.22s)
PASS

--- PASS: TestAccIBMPIInstanceNetwork (1123.39s)
PASS

--- PASS: TestAccIBMPIInstanceReplicant (1914.63s)
PASS

[michaelkad]

@ismirlia could you add the acceptance test for this?

[yussufsh]

@ismirlia could you add the acceptance test for this?

Even I would like to see the interesting results :) This has been the way since how many years I don't know.
@ismirlia Also you will need to handle update flow for every replicant. Good work btw!

[ismirlia]

@yussufsh @michaelkad so right now, update only updates the original instance and not the replicants. Should the goal be to update the replicants as well when any update is made? So this could work for some types of updates potentially, but it couldn't work for others. Like for example you couldn't update the name to match for all of them.

I'm still working on running the tests, got delayed by the reapply quesion @surajsbharadwaj had.

[ismirlia]

@yussufsh updating all of them in one go is also not currently how the API/CLI work in that regard either.

[ismirlia]

Are there any more comments on this? @yussufsh @hkantare ? Updating every replicant at once is not supported, and is not supported by the API. This PR updates just deletion, when including a replicant, and fixes up some of the instance terraform acceptance tests.

[yussufsh]

If instead of delete-wait and loop again, can we have two loops? One loop will delete all the instances and the other loop will check the deletion status. This will save lots of time.

[ismirlia]

Made changes.

[yussufsh]

lgtm

[yussufsh]

lgtm

@ismirlia if an update is not supported can we add a statement in the doc? I am not sure why updating the replicants is not supported. Should be using the same logic as create/delete.

[ismirlia]

lgtm

@ismirlia if an update is not supported can we add a statement in the doc? I am not sure why updating the replicants is not supported. Should be using the same logic as create/delete.

Updating the replicants is not really supported by the semantics of the API. This multi-delete approach is already stretching the supported capabilities of what this resource should do.

The markdown file needs to be updated? pi_instance.html.markdown?

[yussufsh]

I understand but then it is always a possibility that user updates the instance details and expect every replicant is getting updated. Imagine if user changes the memory to reduce cost over 50 instances for example, getting to know after some days that changes did not happen and incurred avoidable expenses.
Anyways I'm also fine adding a warning in instance markdown against replicants, so user understands the risks before using the variable.

[ismirlia]

I made the changes and added the warning:

[yussufsh]

lgtm