terraform-aws-ha-ansible-inventory

main.tf

provider "aws" {
    version = "~> 2.0"
    profile = "personal"
    region  = "${var.region}"
}

data "aws_availability_zones" "healthy_zones" {
  state = "available"
}

data "template_file" "ansible_inventory" {
    template = "${file("templates/hosts.ini.tpl")}"

    vars {
        ha_enabled  = "${var.ha_enabled}"
        master_addr = "${aws_instance.master.public_ip}:${aws_instance.master.private_ip}"
        slave_addr  = "${join(",", formatlist("%s:%s", aws_instance.slave.*.public_ip, aws_instance.slave.*.private_ip))}"
        db_addr     = "${aws_instance.database.public_ip}:${aws_instance.database.private_ip}"
    }
}

resource "local_file" "save_ansible_inventory" {
    content = "${data.template_file.ansible_inventory.rendered}"
    filename = "hosts.ini"
}

resource "aws_instance" "master" {
    ami               = "ami-0085d4f8878cddc81"
    key_name          = "ansible-jfrog.key"
    instance_type     = "t2.nano"
    availability_zone = "${data.aws_availability_zones.healthy_zones.names[0]}"

    tags {
        Name = "ansible-inventory-tpl-master"
    }
}

resource "aws_instance" "slave" {
    ami               = "ami-0085d4f8878cddc81"
    count             = "${var.ha_enabled == "true" ? var.ha_node_count : 0}"
    key_name          = "ansible-jfrog.key"
    instance_type     = "t2.nano"
    availability_zone = "${data.aws_availability_zones.healthy_zones.names[1]}"

    tags {
        Name = "ansible-inventory-tpl-slave${count.index+1}"
    }
}

resource "aws_instance" "database" {
    ami               = "ami-0085d4f8878cddc81"
    key_name          = "ansible-jfrog.key"
    instance_type     = "t2.nano"
    availability_zone = "${data.aws_availability_zones.healthy_zones.names[1]}"

    tags {
        Name = "ansible-inventory-tpl-db"
    }
}

templates-hosts.ini.tpl

[${ha_enabled == "true" ? "ha" : "sa"}-master]
webserver ansible_host=${split(":", master_addr)[0]} private_ip=${split(":", master_addr)[1]}

[${ha_enabled == "true" ? "ha" : "sa"}-database]
db-server ansible_host=${split(":", db_addr)[0]} private_ip=${split(":", db_addr)[1]}

%{ if ha_enabled == "true" ~}
[ha-slave]
%{ for curr_slave_addr in "${split(",", slave_addr)}" ~}
slave${index(split(",", slave_addr), curr_slave_addr)+1} ansible_host=${split(":", curr_slave_addr)[0]} private_ip=${split(":", curr_slave_addr)[1]}
%{ endfor ~}
%{ endif ~}

variables.tf

variable "ha_enabled" {
    type = "string"
    default = "false"
}

variable "ha_node_count" {
    type = "string"
    default = "1"
}

variable "region" {
    type = "string"
    default = "eu-central-1"
}