Part of "Automate hosting a static website on AWS with Terraform" post

s3.tf

resource "aws_s3_bucket" "website_static_files" {
  bucket = var.BUCKET_NAME
  acl    = "private"
  policy = data.aws_iam_policy_document.bucket_website_hosting.json
  website {
    index_document = "index.html"
  }
  force_destroy = true
}

data "aws_iam_policy_document" "bucket_website_hosting" {
  statement {
    actions = [
      "s3:GetObject",
      "s3:ListBucket",
    ]
    principals {
      identifiers = [aws_cloudfront_origin_access_identity.origin_access_identity.iam_arn]
      type        = "AWS"
    }
    resources = [
      "arn:aws:s3:::${var.BUCKET_NAME}",
      "arn:aws:s3:::${var.BUCKET_NAME}/*",
    ]
  }
}

resource "null_resource" "upload_static_files" {
  provisioner "local-exec" {
    command = "aws s3 cp index.html s3://${var.BUCKET_NAME}"
  }
  depends_on = [aws_s3_bucket.website_static_files]
}