Enable null api_token provider configuration

[Conflit-de-Bus]

What is currently missing?

The Aiven provider can not be initialized with null values for the api_token value.

This can cause problems, especially since the addition of application users to Aiven in april.

In our Terraform stacks, we can get application user credentials from another in-house provider. However, because these are created with a resource, they are evaluated after the initialization phase of the provider. Not being able to initialize the provider with a null api_token means a Terraform stack using this principle needs to have its configuration changed after the credentials are generated, to add the Aiven resources after the fact.

If such an operation is attempted now, the following message is returned by the Aiven provider during the terraform plan:

│ Error: token is required for Aiven client
│ 
│   with provider["registry.terraform.io/aiven/aiven"],

Which I guess comes from this part:

terraform-provider-aiven/internal/common/client.go

Line 34 in b4f7493

return nil, fmt.Errorf("token is required for Aiven client")

How could this be improved?

This could be improved if the provider accepted null (or placeholder) values in its initialization phase.

Is this a feature you would work on yourself?

• I plan to open a pull request for this feature.