Terraformer

A CLI tool that generates tf and tfstate files based on existing infrastructure (reverse Terraform).

• Disclaimer: This is not an official Google product
• Status: beta - we still need to improve documentation, squash some bugs, etc...
• Created by: Waze SRE

Table of Contents

• Capabilities
• Installation
• Supported providers
  • Google Cloud
  • AWS
  • OpenStack
  • Kubernetes
  • Github
  • Datadog
• Contributing
• Developing
• Infrastructure

Capabilities

1. Generate tf + tfstate files from existing infrastructure for all supported objects by resource.
2. Remote state can be uploaded to a GCS bucket.
3. Connect between resources with terraform_remote_state (local and bucket).
4. Save tf files using a custom folder tree pattern.
5. Import by resource name and type.

Terraformer uses terraform providers and is designed to easily support newly added resources. To upgrade resources with new fields, all you need to do is upgrade the relevant terraform providers.

Import current state to terraform configuration from google cloud

Usage:
   import google [flags]
   import google [command]

Available Commands:
  list        List supported resources for google provider

Flags:
  -b, --bucket string         gs://terraform-state
  -c, --connect                (default true)
  -f, --filter strings        google_compute_firewall=id1:id2:id4
  -h, --help                  help for google
  -o, --path-output string     (default "generated")
  -p, --path-pattern string   {output}/{provider}/custom/{service}/ (default "{output}/{provider}/{service}/")
      --projects strings
  -r, --resources strings     firewalls,networks
  -s, --state string          local or bucket (default "local")
  -z, --zone string

Permissions

Read-only permissions

Filtering

Filters are a way to choose which resources terraformer imports.

For example:

terraformer import aws --resources=vpc,subnet --filter=aws_vpc=myvpcid --regions=eu-west-1

will import only one VPC and all subnets from all VPCs (not just the ones from the filtered VPC)

Resources ID

Filtering is based on Terraform resource ID patterns. To find valid ID patterns for your resource, check the import part of Terraform documentation.

Planning

The plan command generates a planfile that contains all the resources set to be imported. By modifying the planfile before running the import command, you can rename or filter the resources you'd like to import.

The rest of subcommands and parameters are identical to the import command.

$ terraformer plan google --resources=networks,firewalls --projects=my-project --zone=europe-west1-d
(snip)

Saving planfile to generated/google/my-project/terraformer/plan.json

After reviewing/customizing the planfile, begin the import by running import plan.

$ terraformer import plan generated/google/my-project/terraformer/plan.json

Installation

From source:

1. Run git clone <terraformer repo>
2. Run GO111MODULE=on go mod vendor
3. Run go build -v
4. Run terraform init against an init.tf file to install the plugins required for your platform. For example, if you need plugins for the google provider, init.tf should contain:

provider "google" {}

Or alternatively

4. Copy your Terraform provider's plugin(s) to folder ~/.terraform.d/plugins/{darwin,linux}_amd64/, as appropriate.

From Releases:

• Linux

curl -LO https://github.com/GoogleCloudPlatform/terraformer/releases/download/$(curl -s https://api.github.com/repos/GoogleCloudPlatform/terraformer/releases/latest | grep tag_name | cut -d '"' -f 4)/terraformer-linux-amd64
chmod +x terraformer-linux-amd64
sudo mv terraformer-linux-amd64 /usr/local/bin/terraformer

• MacOS

curl -LO https://github.com/GoogleCloudPlatform/terraformer/releases/download/$(curl -s https://api.github.com/repos/GoogleCloudPlatform/terraformer/releases/latest | grep tag_name | cut -d '"' -f 4)/terraformer-darwin-amd64
chmod +x terraformer-darwin-amd64
sudo mv terraformer-darwin-amd64 /usr/local/bin/terraformer

Using a package manager

If you want to use a package manager:

• Homebrew users can use brew install terraformer.

Links to download terraform providers:

• google cloud provider >2.0.0 - here
• aws provider >1.56.0 - here
• openstack provider >1.17.0 - here
• kubernetes provider >=1.4.0 - here
• github provider >=2.0.0 - here
• datadog provider >1.19.0 - here

Information on provider plugins: https://www.terraform.io/docs/configuration/providers.html

Use with GCP

Example:

terraformer import google --resources=gcs,forwardingRules,httpHealthChecks --connect=true --zone=europe-west1-a --projects=aaa,fff
terraformer import google --resources=gcs,forwardingRules,httpHealthChecks --filter=google_compute_firewall=rule1:rule2:rule3 --zone=europe-west1-a --projects=aaa,fff

List of supported GCP services:

• addresses
  • google_compute_address
• autoscalers
  • google_compute_autoscaler
• backendBuckets
  • google_compute_backend_bucket
• backendServices
  • google_compute_backend_service
• bigQuery
  • google_bigquery_dataset
  • google_bigquery_table
• schedulerJobs
  • google_cloud_scheduler_job
• disks
  • google_compute_disk
• firewalls
  • google_compute_firewall
• forwardingRules
  • google_compute_forwarding_rule
• globalAddresses
  • google_compute_global_address
• globalForwardingRules
  • google_compute_global_forwarding_rule
• healthChecks
  • google_compute_health_check
• httpHealthChecks
  • google_compute_http_health_check
• httpsHealthChecks
  • google_compute_https_health_check
• images
  • google_compute_image
• instanceGroupManagers
  • google_compute_instance_group_manager
• instanceGroups
  • google_compute_instance_group
• instanceTemplates
  • google_compute_instance_template
• instances
  • google_compute_instance
• interconnectAttachments
  • google_compute_interconnect_attachment
• memoryStore
  • google_redis_instance
• networks
  • google_compute_network
• nodeGroups
  • google_compute_node_group
• nodeTemplates
  • google_compute_node_template
• regionAutoscalers
  • google_compute_region_autoscaler
• regionBackendServices
  • google_compute_region_backend_service
• regionDisks
  • google_compute_region_disk
• regionInstanceGroupManagers
  • google_compute_region_instance_group_manager
• routers
  • google_compute_router
• routes
  • google_compute_route
• securityPolicies
  • google_compute_security_policy
• sslPolicies
  • google_compute_ssl_policy
• subnetworks
  • google_compute_subnetwork
• targetHttpProxies
  • google_compute_target_http_proxy
• targetHttpsProxies
  • google_compute_target_https_proxy
• targetInstances
  • google_compute_target_instance
• targetPools
  • google_compute_target_pool
• targetSslProxies
  • google_compute_target_ssl_proxy
• targetTcpProxies
  • google_compute_target_tcp_proxy
• targetVpnGateways
  • google_compute_vpn_gateway
• urlMaps
  • google_compute_url_map
• vpnTunnels
  • google_compute_vpn_tunnel
• gke
  • google_container_cluster
  • google_container_node_pool
• pubsub
  • google_pubsub_subscription
  • google_pubsub_topic
• dataProc
  • google_dataproc_cluster
• cloudFunctions
  • google_cloudfunctions_function
• gcs
  • google_storage_bucket
  • google_storage_bucket_acl
  • google_storage_default_object_acl
  • google_storage_bucket_iam_binding
  • google_storage_bucket_iam_member
  • google_storage_bucket_iam_policy
  • google_storage_notification
• monitoring
  • google_monitoring_alert_policy
  • google_monitoring_group
  • google_monitoring_notification_channel
  • google_monitoring_uptime_check_config
• dns
  • google_dns_managed_zone
  • google_dns_record_set
• cloudsql
  • google_sql_database_instance
  • google_sql_database
• kms
  • google_kms_key_ring
  • google_kms_crypto_key
• project
  • google_project

Your tf and tfstate files are written by default to generated/gcp/zone/service.

Use with AWS

Example:

 terraformer import aws --resources=vpc,subnet --connect=true --regions=eu-west-1 --profile=prod
 terraformer import aws --resources=vpc,subnet --filter=aws_vpc=vpc_id1:vpc_id2:vpc_id3 --regions=eu-west-1

List of supported AWS services:

• elb
  • aws_elb
• alb
  • aws_lb
  • aws_lb_listener
  • aws_lb_listener_rule
  • aws_lb_listener_certificate
  • aws_lb_target_group
  • aws_lb_target_group_attachment
• auto_scaling
  • aws_autoscaling_group
  • aws_launch_configuration
  • aws_launch_template
• rds
  • aws_db_instance
  • aws_db_parameter_group
  • aws_db_subnet_group
  • aws_db_option_group
  • aws_db_event_subscription
• iam
  • aws_iam_role
  • aws_iam_role_policy
  • aws_iam_user
  • aws_iam_user_group_membership
  • aws_iam_user_policy
  • aws_iam_policy_attachment
  • aws_iam_policy
  • aws_iam_group
  • aws_iam_group_membership
  • aws_iam_group_policy
• igw
  • aws_internet_gateway
• nacl
  • aws_network_acl
• s3
  • aws_s3_bucket
  • aws_s3_bucket_policy
• sg
  • aws_security_group
• subnet
  • aws_subnet
• vpc
  • aws_vpc
• vpn_connection
  • aws_vpn_connection
• vpn_gateway
  • aws_vpn_gateway
• route53
  • aws_route53_zone
  • aws_route53_record
• acm
  • aws_acm_certificate
• elasticache
  • aws_elasticache_cluster
  • aws_elasticache_parameter_group
  • aws_elasticache_subnet_group
  • aws_elasticache_replication_group
• cloudfront
  • aws_cloudfront_distribution
• ec2_instance
  • aws_instance

Use with OpenStack

Example:

 terraformer import openstack --resources=compute,networking --regions=RegionOne

List of supported OpenStack services:

• compute
  • openstack_compute_instance_v2
• networking
  • openstack_networking_secgroup_v2
  • openstack_networking_secgroup_rule_v2
• blockstorage
  • openstack_blockstorage_volume_v1
  • openstack_blockstorage_volume_v2
  • openstack_blockstorage_volume_v3

Use with Kubernetes

Example:

 terraformer import kubernetes --resources=deployments,services,storageclasses
 terraformer import kubernetes --resources=deployments,services,storageclasses --filter=kubernetes_deployment=name1:name2:name3

All kubernetes resources that are currently supported by the kubernetes provider, are also supported by this module. Here is the list of resources which are currently supported by kubernetes provider v.1.4:

• clusterrolebinding
  • kubernetes_cluster_role_binding
• configmaps
  • kubernetes_config_map
• deployments
  • kubernetes_deployment
• horizontalpodautoscalers
  • kubernetes_horizontal_pod_autoscaler
• limitranges
  • kubernetes_limit_range
• namespaces
  • kubernetes_namespace
• persistentvolumes
  • kubernetes_persistent_volume
• persistentvolumeclaims
  • kubernetes_persistent_volume_claim
• pods
  • kubernetes_pod
• replicationcontrollers
  • kubernetes_replication_controller
• resourcequotas
  • kubernetes_resource_quota
• secrets
  • kubernetes_secret
• services
  • kubernetes_service
• serviceaccounts
  • kubernetes_service_account
• statefulsets
  • kubernetes_stateful_set
• storageclasses
  • kubernetes_storage_class

Known issues

• Terraform kubernetes provider is rejecting resources with ":" characters in their names (as they don't meet DNS-1123), while it's allowed for certain types in kubernetes, e.g. ClusterRoleBinding.
• Because terraform flatmap uses "." to detect the keys for unflattening the maps, some keys with "." in their names are being considered as the maps.
• Since the library assumes empty strings to be empty values (not "0"), there are some issues with optional integer keys that are restricted to be positive.

Use with Github

Example:

 ./terraformer import github --organizations=YOUR_ORGANIZATION --resources=repositories --token=YOUR_TOKEN // or GITHUB_TOKEN in env
 ./terraformer import github --organizations=YOUR_ORGANIZATION --resources=repositories --filter=github_repository=id1:id2:id4 --token=YOUR_TOKEN // or GITHUB_TOKEN in env

Supports only organizational resources. List of supported resources:

• repositories
  • github_repository
  • github_repository_webhook
  • github_branch_protection
  • github_repository_collaborator
  • github_repository_deploy_key
• teams
  • github_team
  • github_team_membership
  • github_team_repository
• members
  • github_membership
• organization_webhooks
  • github_organization_webhook

Notes:

• Terraformer can't get webhook secrets from the github API. If you use a secret token in any of your webhooks, running terraform plan will result in a change being detected: => configuration.#: "1" => "0" in tfstate only.

Use with Datadog

Example:

 ./terraformer import datadog --resources=monitor --api-key=YOUR_DATADOG_API_KEY // or DATADOG_API_KEY in env --app-key=YOUR_DATADOG_APP_KEY // or DATADOG_APP_KEY in env
 ./terraformer import datadog --resources=monitor --filter=datadog_monitor=id1:id2:id4 --api-key=YOUR_DATADOG_API_KEY // or DATADOG_API_KEY in env --app-key=YOUR_DATADOG_APP_KEY // or DATADOG_APP_KEY in env

List of supported Datadog services:

• downtime
  • datadog_downtime
• monitor
  • datadog_monitor
• screenboard
  • datadog_screenboard
• synthetics
  • datadog_synthetics_test
• timeboard
  • datadog_timeboard
• user
  • datadog_user

Contributing

If you have improvements or fixes, we would love to have your contributions. Please read CONTRIBUTING.md for more information on the process we would like contributors to follow.

Developing

Terraformer was built so you can easily add new providers of any kind.

Process for generating tf + tfstate files:

1. Call GCP/AWS/other api and get list of resources.
2. Iterate over resources and take only the ID (we don't need mapping fields!)
3. Call to provider for readonly fields.
4. Call to infrastructure and take tf + tfstate.

Infrastructure

1. Call to provider using the refresh method and get all data.
2. Convert refresh data to go struct.
3. Generate HCL file - tf files.
4. Generate tfstate files.

All mapping of resource is made by providers and Terraform. Upgrades are needed only for providers.

GCP compute resources

For GCP compute resources, use generated code from providers/gcp/gcp_compute_code_generator.

To regenerate code:

go run providers/gcp/gcp_compute_code_generator/*.go

Similar projects

1. https://github.com/dtan4/terraforming