Slalom Hashicorp Meetup Demo

This repository houses terraform code used to build the infrastructure which was created in the Slalom/Hashicorp meetup demo. Before getting started, I'd recommend a quick browse of the Terraform documentation: https://www.terraform.io/docs/index.html

We use the concept of stacks and modules to help us build our infrastructure in a layered approach. Stacks can be thought of as logical building blocks. A single stack can be made up of a number of modules. Modules are a standard Terraform feature, outlined here: https://www.terraform.io/docs/modules/index.html

As an example, consider the "Network" stack, which lives at terraform/stacks/network. The "Network" stack is comprised of 4 modules: VPC, Public Subnet, Private Subnet and Bastion.

Setup:

Before you attempt to create infrastructure from your local machine using the Terraform code in this repo, you will need to configure the following on your local machine:

1. A version of Terraform

Terraform is an open source product which evolves very quickly. I'm currently running Terraform version 0.11.1. All release versions can be found here: https://releases.hashicorp.com/terraform/

Simply download the correct file for your operating system and unzip it. This will produce a "terraform" executable. Move this executable to somewhere on your machine that makes sense. For example:

/Users/bruce.cutler/Terraform0.11.1/terraform

Make sure that the location of terraform in your filesystem is added to your PATH (we recommend adding an entry to your .bashrc or .bash_profile if on Linux).

Once setup is complete, the easy way to check that terraform is configured correctly is to enter "terraform -version" in your shell/command prompt which should return information about the downloaded version.

2. Install and configure AWS Command Line Interface (CLI)

Follow the steps outlined in this document to install the AWS CLI: http://docs.aws.amazon.com/cli/latest/userguide/installing.html

Next, you need to generate an Access Key/Secret Access Key combination. Follow the section titled "To create, modify, or delete a user's access keys" from this document: http://docs.aws.amazon.com/IAM/latest/UserGuide/id_credentials_access-keys.html

Finally, configure the AWS CLI to use the credentials above by following this document: http://docs.aws.amazon.com/cli/latest/userguide/cli-chap-getting-started.html

3. Create S3 bucket(s) for state files

Follow the steps outlined in this document to create an S3 bucket to hold your state files: https://docs.aws.amazon.com/AmazonS3/latest/gsg/CreatingABucket.html

Creating Infrastructure with Terraform

Once you have performed the above configuration steps, you can build infrastructure from this repo:

1. Clone the repo locally (git clone https://github.com/BruceCutler/slalom-hashicorp-demo)

2. To configure your newly created S3 bucket with the correct AWS region, you must update/create the appropriate file at tools/aws/terraform/region/<region>/geo_config.sh.

   For example, notice that in tools/aws/terraform/region/us-east-1 I have geo_config.sh that ensures my bucket name is exported and available to the wrapper deployment script

3. Terraform is called using a wrapper script, found at tools/aws/terraform/tf_deploy inside the cloned repo

4. tf_deploy takes 3 arguments: -r, -t, -s

   -r = region (Example: us-east-1 or eu-west-1)

   -t = target (Example: dev/stg)

   -s = stack (Example: network)

   In addition to the above arguments, you must also supply a command such as plan or apply

5. As an example, to see a plan of the dev network stack in us-east-1, our command would be:

   $ tools/aws/terraform/tf_deploy -r us-east-1 -t dev -s network plan

6. If the plan looks good, we can run apply to create the dev network stack infrastructure in us-east-1 using:

   $ tools/aws/terraform/tf_deploy -r us-east-1 -t dev -s network apply

7. Finally, to destroy resources that you have created as part of the dev network stack, you should run:

   $ tools/aws/terraform/tf_deploy -r us-east-1 -t dev -s network destroy -force