tf-inventory

tf-inventory

tf-inventory is a little tool to generate Ansible dynamic inventory file from Terraform state file. It is inspired of the work of adammck: terraform-inventory.

tf-inventory parses the resources in each module. If the resource type is supported, it will get the hostname and ip from the instance. In Ansible, hostname and ip will be used respectively as the host's name and ansible_ssh_host.

If Terraform module is not used in TF files (only one module with Path root), the name of supported resource will be the group name even in the case of multiple instances of a resource. Otherwise, servers will be grouped under the name given by the 2nd element of Module.Path.

tf-inventory considers Terraform outputs as group variables in Ansible. If the output is a map, then each element of the map will be considered as a group var distinct.

Actually, the following providers are supported:

• Vsphere
• Scaleway

Installation

To use tf-inventory, you have to clone this repository and build it as following:

# git clone https://github.com/uthng/tf-inventory
# cd tf-inventory
# GO111MODULE=on make deps build
# ./releases/<yourplatform>/tf-inventory

Usage

You can use tf-inventory alone or with ansible.

CLI

tf-inventory --help
usage: tf-inventory [<flags>] [<tfsfile>]

An utility to generate ansible inventory file from Terraform state

Flags:
  --help       Show context-sensitive help (also try --help-long and --help-man).
  --list       List mode
  --host=HOST  Host mode

Args:
  [<tfsfile>]  Terraform state file

tf-inventory gets the content of Terraform state file in 3 following ways in order:

1. tfsfile: if it is specified, tf-inventory will read and parse its contents
2. consul: if the following environment variables are specified, tf-inventory will get the tfstate content with the given key from Consul
   • CONSUL_URL: Consul server's url
   • CONSUL_KEY: Consul key containing tfstate
   • CONSUL_TOKEN: Consul token to access to key
3. terraform: if 2 above cases donot satisfy, tf-inventory will perform the command terraform state pull to generate tfstate instead using the following environment variables:
   • TF_BIN: path to folder containing terraform binary
   • TF_DIR: path to Terraform working folder.

Otherwise, it will return an error.

Using tfstate argument:

./tf-inventory --list ./fixtures/terraform.tfstate

Using TF_DIR:

TF_DIR=/path/to/terraform ./tf-inventory --list

With Ansible

When using with Ansible, the current directory must be a Terraform working folder:

ansible -i /path/to/tf-inventory my-host -m ping

If not, TF_DIR must be used to specify it:

TF_DIR=/path/to/terraform/ ansible -i tf-inventory my-host -m ping