terraform-3-to-4-s3-imports.sh

#!/bin/bash
# AUTHOR: github.com/asaf400
# This script iterates over all S3 objects in terraform state,
# in order to import any S3 resource that has been split from the main aws_s3_bucket resource
# following the terraform aws v4 breaking changes which requires existing s3 attributes to exists as 'linked' resources
# The script assumes that the hcl files has already been modifed to reflect the v4 change, 
# and it is useful for allowing terraform to import the new resources which already existed in aws.
# SCRIPT IS DISTRIBUTED AS IS, NOT SUPPORT REQUESTS.

# The resources are: 
# aws_s3_bucket_server_side_encryption_configuration
# aws_s3_bucket_lifecycle_configuration
# aws_s3_bucket_versioning
# aws_s3_bucket_cors_configuration
# aws_s3_bucket_acl

terraform_directory="$1"

pushd "$terraform_directory"
terraform show -json >/tmp/terraform-state.json
popd

function log_found() {
  echo -e "  \e[32m$1 is:\e[0m\n$2\n"
}

function log_notfound() {
  echo -e "  \e[33mno $1:\e[0m\n$2\n"
}

function log_error() {
  echo -e "  \e[31mERROR: $1\e[0m\n"
}

function handle_terraform_import() {
  if [[ $1 == "acl" ]]; then
    acl=",$(jq -r .values.acl <<<"$full_object")"
  else
    acl=""
  fi

  echo -e "Would perform:\n# terraform import $(sed 's/aws_s3_bucket/aws_s3_bucket_'"$1"'/' <<<"$object") "$bucket_name""$acl""
  echo -e "To remove: # terraform state rm $(sed 's/aws_s3_bucket/aws_s3_bucket_'"$1"'/' <<<"$object")"

  status="$(terraform import $(sed 's/aws_s3_bucket/aws_s3_bucket_'"$1"'/' <<<"$object") "$bucket_name""$acl")"
  if [ $? -ne 0 ]; then
    log_error "!!!!\n!!!! Failed to Import resource !!!!\n$status\n!!!!"
  else
    log_found "Successfully Imported Resource!" "$object"
  fi
}

function jq_find_object(){
	jq '..|objects|select(has("'$2'") and .'$2' == "'$3'")' $1
}

function process_value() {
  resource_name=$1
  resource=$2
  condition=$3
  if [[ $resource != "$condition" ]]; then
    log_found $resource_name $resource
    handle_terraform_import $resource_name
  else
    log_notfound $resource_name $resource
  fi
}

pushd "$terraform_directory"
terraform init -upgrade

objects="$(jq_find_object "/tmp/terraform-state.json" type aws_s3_bucket | jq -r .address)"
echo "$objects"

for object in $objects; do
  full_object="$(jq_find_object "/tmp/terraform-state.json" address $object)"
  echo "---- Working on $object ----"

  bucket_name="$(jq -r '.values.bucket' <<<"$full_object")"

  server_side_encryption_configuration="$(jq -c '.values.server_side_encryption_configuration?' <<<"$full_object")"
  lifecycle_rule="$(jq -c '.values.lifecycle_rule?' <<<"$full_object")"
  versioning="$(jq -c '.values.versioning?' <<<"$full_object")"
  cors_rule="$(jq -c '.values.cors_rule?' <<<"$full_object")"

  process_value server_side_encryption_configuration $server_side_encryption_configuration ""
  process_value lifecycle_configuration $lifecycle_rule "[]"
  process_value versioning $versioning "[]"
  process_value cors_configuration $cors_rule "[]"

  handle_terraform_import acl
done