crash when bucket logging block is empty

[ghost]

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Terraform Version

$ terraform -v
Terraform v1.3.4
on darwin_arm64
+ provider registry.terraform.io/hashicorp/google v4.43.0
+ provider registry.terraform.io/hashicorp/google-beta v4.43.0
+ provider registry.terraform.io/hashicorp/null v3.2.0
+ provider registry.terraform.io/hashicorp/random v3.4.3
+ provider registry.terraform.io/hashicorp/time v0.9.1

Affected Resource(s)

• google_storage_bucket

Terraform Configuration Files

variable "log-bucket" {
  type    = string
  default = ""
}
# set up a bucket for access logging, with some readonly grants
resource "google_storage_bucket" "_" {
  name                        = var.name
  location                    = "US"
  uniform_bucket_level_access = true
  public_access_prevention    = "enforced"

  logging {
    log_bucket = var.log-bucket
  }
  }

Debug Output

upon request

Panic Output

It's short enough IMO:

panic: interface conversion: interface {} is nil, not map[string]interface {}                                                                                                         
                                                                                                                                                                                      
goroutine 106 [running]:                                                                                                                                                              
github.com/hashicorp/terraform-provider-google/google.expandBucketLogging(...)                                                                                                        
        github.com/hashicorp/terraform-provider-google/google/resource_storage_bucket.go:970                                                                                          
github.com/hashicorp/terraform-provider-google/google.resourceStorageBucketUpdate(0x14000c55e00?, {0x102c4ec00?, 0x14000aa9000})                                                      
        github.com/hashicorp/terraform-provider-google/google/resource_storage_bucket.go:623 +0x1794                                                                                  
github.com/hashicorp/terraform-plugin-sdk/v2/helper/schema.(*Resource).update(0x102c8f6a8?, {0x102c8f6a8?, 0x14000c6d320?}, 0xd?, {0x102c4ec00?, 0x14000aa9000?})                     
<snip>                                                                                                                     
                                                                                                                                                                                      
Error: The terraform-provider-google_v4.43.0_x5 plugin crashed!

Expected Behavior

A GCS bucket should be successfully provisioned, with no "log bucket" configured.

Actual Behavior

See above panic.

Steps to Reproduce

1. terraform apply

Important Factoids

[ghost]

The workaround is to ensure that there is never an empty logging block:

  dynamic "logging" {
    for_each = var.log-bucket == "" ? [] : [var.log-bucket]
    content {
      log_bucket = var.log-bucket
    }
  }

This is a pretty involved workaround however, and it took me more than a couple minutest to realize this was the cause of the panic.

[github-actions]

I'm going to lock this issue because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active issues.
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