Deploying Terraform in Azure using Github Actions workflow

 This article will summarise the steps I went through to set up Github Actions with a private repo to be able to push Terraform code from VS Code to Github and then to Azure.

It is based on a great article by Guillermo Musumeci and if you want to replicate this setup, that is the guide you should follow, see article.

The overall steps are as follows:

• Create a Service Principal (SPN) with contributor permissions
• Create a storage account and a container (this is used to hold the backend state and is created up front. I did this via AZ CLI but any method, such as via the Azure Portal, will do)
• Create a Private Repo in Github
• From VS Code, clone the repo to your local machine
• Add 4 x secrets to Github under your private repo: Repo -> Settings -> Secrets -> Actions -> New Repo Secret (these secrets contain the SPN info so that Github Actions can authenticate towards Azure
• Create providers.tf, variables.tf, outputs.tf files according to article mentioned above. And a main.tf file that just contains a resource group to get started
• Create Github Actions workflow using a simple Terraform YAML pipeline file

These are the base steps. From now on when you create a pull request (PR), the workflow will start and will run terraform init, plan, and apply and if there are no issues the code will be pushed. It doesn't wait for you to complete the PR though but you can do that as the last step.

Under Actions, you can see the status of all the workflow runs (it looks quite similar to a push pipeline run in Azure DevOps):

In the repo I have just placed all the files in the root folder. This works but can likely be organised better as the amount of files grow, see below:

I ran into two minor issues, these were:

An error message saying the following:

"Error message: state blob is already locked" and "Terraform acquires a state lock to protect the state from being written by multiple users at the same time. Please resolve the issue above and try again. For most commands, you can disable locking with the "-lock=false" flag, but this is not recommended."

I tried updating the pipeline file to include the -lock=false under the "terraform plan" command but that didn't work. For some reason I had a lock on the state file in the storage account that was created earlier. From the Azure Portal, you can navigate to the file in the blob container and from there remove the lock (or break the lease, is the terminology, see screenshot below). After doing this, there has been no more issues with the lock.

The other issue I ran into was that when I tried to deploy the first resource, the workflow was hanging for a long time and it was unclear what was holding it up.

It turns out that it was waiting for the Microsoft.DocumentDB resource provider to be registered. This is a one time thing that is done on the under the subscription under Resource Providers (it specifies which resource types are allowed and not all resource types are allowed by default). I would recommend to just go and enable/register it manually before running the Actions workflow (it takes some time for it to register, maybe 30-40 mins).

Once this was in place the workflow has been running smoothly and any errors has been related to my code but the error messages have been pretty clear so it has been easy to address.

That's it. It may seem like a lot initially, but if you take step by step, it's not that bad. And the final setup is quite cool and useful.