How to Import an AWS S3 Bucket Policy into Terraform

Import AWS S3 Bucket Policy 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 Policy 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_policy.assets
  id = "my-app-assets"
}

Example aws_s3_bucket_policy configuration

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

resource "aws_s3_bucket_policy" "assets" {
  bucket = "my-app-assets"

  policy = jsonencode({
    Version = "2012-10-17"
    Statement = [{
      Effect    = "Allow"
      Principal = { Service = "cloudfront.amazonaws.com" }
      Action    = "s3:GetObject"
      Resource  = "arn:aws:s3:::my-app-assets/*"
    }]
  })
}

Gotchas when importing a AWS S3 Bucket Policy

• The import ID is the bucket name only, not an ARN.
• The bucket policy is a resource separate from the aws_s3_bucket; import both if you manage the bucket and its policy.
• The policy JSON must match the live document including the provider's normalization, or Terraform plans an update on first apply.
• Only one bucket policy can exist per bucket; declaring two aws_s3_bucket_policy resources for the same bucket overwrites unpredictably.

Doing it manually with terraform import

The native approach is to write the aws_s3_bucket_policy block by hand, then run terraform import aws_s3_bucket_policy.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