Chapter 4: The Core Terraform Workflow

According to the official documentation, the core workflow for using Terraform involves three steps:

1. Write - Author infrastructure as code.

2. Plan - Preview changes before applying.

3. Apply - Provision reproducible infrastructure.

Let's elaborate on how these steps apply to using Terraform with Azure:

1. Configure your Azure credentials: To authenticate with Azure, you will need to provide your Azure subscription ID and a user or service principal with the appropriate permissions. Service Principal authentication is usually the preferred method. You can create a service principal using the Azure CLI or the Azure portal, and then store the credentials in a configuration file or as environment variables.

2. Write your Terraform configuration: Next, you will need to write your Terraform configuration, which consists of one or more .tf files that define the resources you want to create in Azure. Your configuration should specify the type of resources you want to create, their properties, and any dependencies between resources.

3. Initialize Terraform: Before you can use Terraform to create resources in Azure, you will need to initialize it by running the terraform init command. This command will download any required plugins/modules and initialize the local Terraform state file if it is defined in the code.

4. Validate your configuration: You can use the terraform validate command to check your configuration for syntax errors and other issues. This can help you catch mistakes early on and ensure that your configuration is correct.

5. Preview your changes: To see what changes Terraform will make to your Azure resources, you can use the terraform plan command. This command will show you a summary of the changes that will be made, including the resources that will be created, modified, or destroyed.

6. Apply your changes: When you are ready to create the resources in Azure, you can use the terraform apply command. This command will create the resources in Azure and update the local Terraform state file to reflect the current state of your resources.

7. Manage your resources: Once your resources are created, you can use Terraform to manage them over time. This can involve making changes to your configuration.

The above workflow is the overall outline when working with Terraform for Azure, but it may seem a bit abstract. In the next chapter, we will have the opportunity to apply these steps in real examples. This will help us better understand how to use these workflow steps in a practical context.