Setting up Scalr & Azure DevOps Part 1 - Picking a Workflow

This was written by Jack Roper, a guest blogger.

Getting started with Scalr and Azure DevOps takes 3 stages. This series of 3 posts walks through each one step by step.

This first post covers stage 1, picking a workflow.

Post 2 in the series will describe how to add Azure credentials and link them to an environment.

And finally, post 3 in the series will focus on how to execute your Terraform code and create a workspace, both using PR automation, and by plugging the CLI into Azure DevOps. There is a third way to create a workspace using the module registry as well, but this still uses the VCS connection.

Let's go!

What is Scalr?

Scalr is Terraform Automation and Collaboration (TACO) software. It supports pull request automation, the native Terraform CLI, or module-driven workflows. The way it scales for organizations of any size is a hierarchical model that centralizes admin operations like RBAC, policy control through OPA, operational views, and a private module registry. That gives you controlled decentralization: developers can run their own Terraform workflows inside environments without stepping on each other.

Also from https://docs.scalr.io/docs:

Scalr is a remote operations backend for Terraform. What does this mean in basic terms? It executes Terraform operations and stores state, regardless of the workflow, in Scalr itself allowing for easy collaboration across your organization. That means you can easily onboard an existing GitOps or native Terraform CLI based workflows into Scalr with little to no modification to your actual code.

Getting Started

The 2 ways to get started with Scalr depending on your workflow are:

1. Adding the Version Control System (VCS) provider, in this case, Azure DevOps.
2. Using the Terraform CLI in the Azure DevOps pipeline.

Authenticate to Scalr with Azure DevOps

First, we will need to choose the project in Azure DevOps you want to link with Scalr. I've set up a test one:

Inside my Project, I have a repo called Scalr with some basic terraform files. When you apply the configuration, it creates a given number of Azure AD Groups.

main.tf

provider "azurerm" {
  features {}
}
 
terraform {
  required_providers {
    azurerm = {
      source  = "hashicorp/azurerm"
      version = ">=2.95.0"
    }
    azuread = {
      source  = "hashicorp/azuread"
      version = ">=2.17.0"
    }
  }
  backend "azurerm" {
    // resource_group_name  = "tf-rg"
    // storage_account_name = "jacktfstatesa"
    // container_name       = "terraform"
    // key                  = "adgroups.tfstate"
  }
}
 
resource "azuread_group" "ad_group" {
  count = 3
  display_name = var.ad_group_names[count.index]
  security_enabled = false
  mail_enabled = false
}

variables.tf

variable ad_group_names {
    type = list(string)
    description = "List of all the AD Group names"
}

terraform.tfvars

ad_group_names = ["Group1", "Group2", "Group3"]

Setup the Azure DevOps integration using the web interface

Scalr can Integrate with several VCS providers to automate your GitOps workflow. Let's run through setting it up with our Azure DevOps repo step-by-step!

When you first log in to your Scalr account, you will be greeted with the following:

Clicking on 'create VCS provider' and then 'Azure' presents the following options:

1. Enter your provider name (e.g. AzureDevOpsProject)
2. Hit the 'Register a new OAuth application in Azure' button, it will take you to register an App in Azure DevOps: https://aex.dev.azure.com/app/register

3. Copy the callback URL and paste it into the Authorization callback URL in the Azure DevOps page

4. Under authorized scopes, tick code (read) and code (status).

5. Fill in the company name, Application Name, and Application website fields, then hit 'create application'. Your application settings will be presented:

6. Back in Scalr, paste your app ID and client secret and press 'create':

7. Hit accept:

8. Scalr will now show the Azure DevOps is connected.

Authenticate to Scalr with the Terraform CLI

If an existing workflow already exists that utilizes the native Terraform CLI or you just want the flexibility to use it, you can continue to use the Terraform CLI as it is fully supported in Scalr. Scalr will execute the runs in a container in the Scalr backend, but the logs and output will still be sent back to your console. To utilize Scalr as a remote backend there are a few simple steps:

1. Obtain an API token by running terraform login <account-name>.scalr.io
2. Create a workspace
3. Execute terraform init

terraform login jackwesleyroper.scalr.io

Press 'Create API Token', then copy the resulting ID and Token.

The token should be displayed in Scalr.

Paste the token back into the command window:

The Scalr Terraform Provider

One more thing worth knowing: the Scalr Terraform provider can manage the components inside Scalr. So you can automate creating workspaces, variables, VCS providers, and a lot more.

Summary

We connected our VCS provider, Azure DevOps, to Scalr, and we walked through authenticating to Scalr with the Terraform CLI.

Part 2 in the series looks at how to add Azure credentials and link them to an environment.

Cheers! 🍻