A script that generates terraform import blocks from existing terraform resource states

generate-tf-imports.sh

#!/usr/bin/env bash

declare -A resource_id_map=( # terraform resource type -> jq expression for its import id
    [aws_lb]=.arn
    [aws_lb_listener]=.arn
    [aws_lb_target_group]=.arn
    [aws_security_group]=.id
    [aws_vpc_security_group_ingress_rule]=.security_group_rule_id
    [aws_vpc_security_group_egress_rule]=.security_group_rule_id
    [aws_iam_role]=.name
    [aws_iam_role_policy]='"\(.role):\(.name)"'
    [aws_ecs_cluster]=.name
    [aws_ecs_cluster_capacity_providers]=.cluster_name
    [aws_ecs_service]='"\(.cluster|sub("^.*/"; ""))/\(.name)"'
    [aws_ecs_task_definition]=.arn
    [aws_kms_key]=.id
    [aws_kms_alias]=.name
    [aws_route53_record]=.id
    [aws_secretsmanager_secret]=.arn
    [aws_secretsmanager_secret_version]=.id

    # Feel free to look up the documentation and add the jq expression for the import id
    # For example, according to https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/s3_bucket#import
    # the import id for 'aws_s3_bucket' is the bucket name, which is available from the terraform state (
    # made available via "$state_attributes_json" in 'generate-imports' below), so you would add an entry here like so:
    #
    #   [aws_s3_bucket]=.id
    #
    # to teach the script how to get the import id for any aws_s3_bucket resources.
    #
)

generate-imports () {
    local state_attributes_json; state_attributes_json=$(
        terraform state pull | jq '
          [
            .resources[]
            | select(.mode == "managed")
            | (if .module then "\(.module)." else "" end) as $module
            | .instances[] as $inst
            | (if $inst.index_key then "[\($inst.index_key|tojson)]" else "" end) as $index
            | {
                "key": "\($module)\(.type).\(.name)\($index)",
                "value": $inst.attributes
            }
          ] | from_entries
        ' # | tee state_attributes.json 
          # NOTE: Uncomment to see the json that can be used for mapping a resource type to
          # its import id used in the resource_id_map above.
    )

    local source_state_name
    while read -r source_state_name; do
        resource_type=${source_state_name#module.*.}
        resource_type=${resource_type%%.*}
        cat <<EOF
import {
  id = $(jq --arg key "$source_state_name" ".[\$key] | ${resource_id_map[$resource_type]:?}" <<<"$state_attributes_json")
  to = $(map-tf-state-name)
}
EOF
    done
}

map-tf-state-name () {
    : TODO: implement your mapping logic here and output the target resource id
    # NOTE: You are free to reference variables (e.g., $source_state_name or even $state_attributes_json)
    #       in the call chain.
}


terraform state list | egrep -v 'data\.' \
    |
generate-imports