How to Import an AWS S3 Bucket Logging into Terraform

Import AWS S3 Bucket Logging with Terraback (recommended)

Terraback reverse-engineers your live infrastructure: it reads the Amazon S3 resource with read-only credentials, generates the HCL, and produces the exact import block. Two commands take you from a live AWS S3 Bucket Logging to managed Terraform.

terraback scan all aws --region us-east-1

terraback aws import --method bulk

The Terraform import block

Terraback emits a Terraform 1.5+ import block like the one below. Because the block lives in your configuration, the import is reviewable in a pull request and repeatable across environments.

import {
  to = aws_s3_bucket_logging.example
  id = "my-app-assets"
}

Example aws_s3_bucket_logging configuration

Here is a realistic AWS S3 Bucket Logging block. Terraback generates a fuller version from your actual resource attributes; this is a minimal, valid starting point.

resource "aws_s3_bucket_logging" "example" {
  bucket        = "my-app-assets"
  target_bucket = "my-app-logs"
  target_prefix = "s3-access-logs/"
}

Gotchas when importing a AWS S3 Bucket Logging

• Server access logging is a standalone sub-resource imported by the source bucket name; the source bucket and the target_bucket are separate aws_s3_bucket resources you import on their own.
• When expected_bucket_owner was used, the import ID is bucket,account-id (comma separated) rather than just the bucket name.
• The target_bucket must grant S3 log delivery permissions; importing the logging config does not import or fix those target bucket ACL/policy grants.
• Do not also set the deprecated inline logging block on aws_s3_bucket; combining inline logging with this resource produces a constant diff.

Doing it manually with terraform import

The native approach is to write the aws_s3_bucket_logging block by hand, then run terraform import aws_s3_bucket_logging.example <import-id> for every resource, one at a time. That works for a handful of resources, but it does not scale: you author all the HCL yourself and repeat the command for each item. Terraback generates the HCL and the import blocks for your whole account in one pass.

Import other AWS resources