add mutex for apigee_instance

[xuchenma]

This PR adds a mutex for apigee_instance, so that multiple instances for the same org will be created in sequence.
Closing hashicorp/terraform-provider-google#10525

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Release Note Template for Downstream PRs (will be copied)

apigee: fixed a bug where multiple `google_apigee_instance` could not be used on the same `google_apigee_organization`

[modular-magician]

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I have detected that you are a community contributor, so your PR will be assigned to someone with a commit-bit on this repo for initial review.

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@slevenick, please review this PR or find an appropriate assignee.

[modular-magician]

Hi! I'm the modular magician. Your PR generated some diffs in downstreams - here they are.

Diff report:

Terraform GA: Diff ( 1 file changed, 14 insertions(+))
Terraform Beta: Diff ( 1 file changed, 14 insertions(+))
TF Validator: Diff ( 2 files changed, 3 insertions(+), 3 deletions(-))

[slevenick]

I think we want to scope the lock to only Apigee Instances rather than the org in general. How about a mutex like "organizations/{{org_id}}/apigeeInstances"?

[xuchenma]

Yes we want to lock only Apigee instances. I tried to change it to "{{org_id}}/instances", but strangely, in my local testing, although it was able to create 2 instances in sequence, it failed to delete them, complaining the resource is locked by another operation.
Could you explain more about what the syntax means? Or should I change it to exactly organizations/{{org_id}}/apigeeInstances?

[slevenick]

Yes we want to lock only Apigee instances. I tried to change it to "{{org_id}}/instances", but strangely, in my local testing, although it was able to create 2 instances in sequence, it failed to delete them, complaining the resource is locked by another operation. Could you explain more about what the syntax means? Or should I change it to exactly organizations/{{org_id}}/apigeeInstances?

I think that organizations/{{org_id}}/apigeeInstances should work, but I haven't tested it. That error message you saw, is that coming from the API or the Terraform provider? I haven't found anywhere in the provider that would produce that message, so maybe it's an API-side error about deletion?

[xuchenma]

Thanks, I've changed it to {{org_id}}/apigeeInstances because {{org_id}} is in the form organizations/xxx(it contains the organizations/ already). Local testing has also worked for me.

[modular-magician]

Hi! I'm the modular magician. Your PR generated some diffs in downstreams - here they are.

Diff report:

Terraform GA: Diff ( 1 file changed, 14 insertions(+))
Terraform Beta: Diff ( 1 file changed, 14 insertions(+))
TF Validator: Diff ( 2 files changed, 3 insertions(+), 3 deletions(-))