vscode-infracost VS atlantis

Hi, we are Ali, Hassan, and Alistair, co-founders of Infracost (https://www.infracost.io/). Infracost helps engineers see the cost of each Terraform change before launching resources. When changes are made, it posts a comment with the cloud cost impact. For example, “you’ve added 2 instances and volumes, and change an instance type from medium to large, your bill will increase by 25% next month, from $1000 to $1250 per month”.

We launched in February 2021 (https://news.ycombinator.com/item?id=26064588), and Infracost is now being actively used by over 3,000 companies. However, there is a shift happening in the cloud cost management space. New teams, called FinOps teams (a combination of "Finance" and "DevOps"), are being formed within companies to manage cloud costs.

One of the first tasks assigned to these teams is to determine "who is using what" - that is, which teams, business units, products, etc. are spending the most on cloud. To accomplish this, they use tags. Tags are labels that all cloud resources should have and are key-value pairs. For example, a server could be tagged with: product=HackerNews; environment=production; team=blueTeam. So if resources are not tagged properly, then you can’t tell who is using what.

However, FinOps teams face challenges because their tools are reactive. These tools begin by analyzing cloud bills and providing visibility of tags from there. This means that they are looking at resources that are already running in production and costing money. A customer recently shared, “I want all resources to be properly tagged. But if they are not, I would rather a resource not be tagged at all than be tagged incorrectly.”

My "aha" moment! FinOps teams can define a tagging policy that can be validated in CI/CD before resources are launched. This is important because if code is shipped with the wrong tags, FinOps teams will have to fight for sprint time to fix them. Even if you shut down an untagged resource directly in the cloud, the next time Terraform runs, the resource will launch again with no tag. You need to fix the issue at its root.

I’d love your feedback on our solution to the tagging problem. You define your tag key-value policy in our SaaS product, and Infracost checks all Terraform resources per change. If anything fails the policy, it posts a comment with the details of which resources need tags, and what the allowed values are. Once fixed, it will let the code be shipped to production.

Try it out by going to https://dashboard.infracost.io/, setting up with the GitHub app or GitLab app, and defining your tagging policy. It will then scan your repository and inform you of any missing tags and their file and line number. You can use the free trial, but if you need more time, please message me and I’ll extend it for you.

I would also love to hear how others ensure that the correct tag keys and values are applied to all resources, and whether this is done proactively or reactively. Additionally, I would be interested in hearing about any lessons learned in the process.

Cheers

Great toolchain, including Infracost or tfsec.

Infracost is an open-source tool for estimating the cost of cloud infrastructure using Infrastructure as Code templates.

Throughout this post, you will see me mention the cost of running this using an estimate. I have been using for a while, a tool called infracost which is an open source (with subscription based additions) cost estimator tool - https://www.infracost.io/. For this demonstration, using the sample code listed above, it would cost an estimated $76.65/month - so if you don't want rack up a bill, only deploy when you want to test, and use Terraform to destroy the services when you are done.

Infracost : Infracost is an open-source tool that allows users to see the cost of running their infrastructure, such as AWS resources, in near real-time. It uses the AWS Price List API to determine the costs of resources, and can be integrated into CI/CD pipelines to provide cost feedback during the development process. This allows developers to make informed decisions about their infrastructure and optimize costs. Additionally, Infracost can be used to create alerts based on cost thresholds, so you can be notified when your infrastructure costs exceed a certain amount. This can be especially useful for teams that operate on a tight budget or need to manage costs closely.

An Infracost API key. You can get one by signing up for free at Infracost.io.

Since Wing compiles to Terraform, you should be able to manually run Infracost (https://www.infracost.io) to get an idea of costs.

Having that capability baked into the language/compiler would be a great addition.

None of these are a replacement of Terraform Cloud (recently rebranded to HCP Terraform). For example, when you create a PR, it could affect multiple workspaces. The new experimental version of TFC/TFE (I refuse to call it HCP!) implements Stacks, which is something like a workflow, and links one workspace output to other workspace inputs. None of the open-source solutions, including the paid Digger [0], support this - only the paid one, such as Spacelift [1] (which is the closest to TFC if you ask me). Having a monorepo of Terraform is a common design pattern, so, if I change an embedded module, it could trigger changes it many workspaces. As far as I know, Atlantis [2] can't really help in this case.

By the way, the reason I singled-out Spacelift is due to its quality, and the great Terraform provider it has. Scalr [3], for example, has a really low-quality Terraform provider. I extensively use the hashicorp/tfe provider to manage TFC itself.

[0]: https://digger.dev/

[1]: https://spacelift.io/

[2]: https://www.runatlantis.io/

[3]: https://www.scalr.com/

Atlantis is a pull request automation tool that works well with plain Terraform right away. But what if we're already using Terramate to generate Terraform code?

Atlantis automates reviewing and deploying Terraform via pull requests, streamlining collaboration and ensuring consistency across Terraform deployments.

For example, Atlantisgo for Terraform, Zapier’s Kubechecks for Argo CD, Quizlet’s GitHub action all do something similar to this. But a generic, extensible tool for IaC providers doesn’t seem to exist. Additionally, many of them require exposing your Kubernetes cluster or other infrastructure to third-party access, webhooks, etc.

Our first attempt was to introduce other engineering teams to Terraform - the Platform team was already using it extensively with Terragrunt, and using Atlantis to automate plan and apply operations in a Git flow to ensure infrastructure was consistent. We'd written modules, with documentation, and an engineer would simply need to raise a PR to use the module and provide the right values, and Atlantis (once the PR was approved by Platform) would go ahead and set it up for them.

Alternatively, you can look at solutions like Atlantis or spacelift.

Atlantis: https://www.runatlantis.io/

Looking at the commits at https://github.com/runatlantis/atlantis, it looks like 1.6.5. Am I right?

We use Atlantis [0] for CI/CD automation of Terraform pull requests to a centralized repository. It's pretty good too, especially for a self-hosted solution. I can't see how Terraform Cloud's costs would be justifiable for us without a custom contract.

[0] https://www.runatlantis.io/