Terraform File Extensions
Terraform is based on the Hashicorp Configuration Language, or HCL. It actually uses two types of configuration formats, represented by the file extensions you use to save your Terraform configuration:
.tf(Standard Terraform Configuration Files): This is the most common extension used for Terraform configurations. It contains native HCL code in configuration files. As HCL is very human-readable, its structure is defined by indentation and keywords to define configuration blocks and key-value pairs.
.tf.json(JSON-formatted Terraform Configuration Files): If you prefer writing in JSON syntax, or your project is very heavily JSON-dependent, you can have a .tf.json extension. Using the .tf.json extension allows you to express configurations in a familiar JSON syntax with an already well-established structure.
The choice of extension depends on your personal preference and the requirements of your project. Both formats share the same functionality and allow for good management of infrastructure as code.
Basic Terraform Configuration File Naming Convention
Terraform recommends a set of file naming conventions to help structure your infrastructure as code configurations. This makes it easier to read and understand, navigate, and maintain your code. Let's now dive into each of the different file types and their respective purposes:
1. main.tf
The main file you will use to specify your infrastructure resources that you wish to create, update, or manage using Terraform is known as the main file. It forms the entry point for the
Terraform commands, such as terraform apply and terraform plan. When such commands are run, Terraform looks at all the resources declared in the main.tf file, and based on it, determines what steps it needs to take to bring your infrastructure into the state you want.
It carries resource blocks
2. data.tf
data.tf is used to define data sources, meaning a method by which you can fetch information from outside sources and then use this information in your Terraform configuration. This enables you to import resource details coming from external sources and use them within your infrastructure as code, thus making it more dynamic and flexible to your configuration.
It carries data blocks
3. variables.tf
variables.tf is used for defining your variables in Terraform. These allow your configurations to parameterize so that it becomes adaptable to different environments, configurations, and even use cases.
It contains the variable blocks
4. outputs.tf
outputs.tf is used for declaring your output values. These are the values that are to be computed after Terraform finishes deploying (or creating) your infrastructure.
It contains the output blocks
5. terraform.tf
terraform.tf is used for defining the required version of Terraform and the required providers to manage your defined resources within your main.tf.
The terraform file comprises the terraform blocks
6. providers.tf
providers.tf is used to define providers. This is the central location that you use to define and configure all of the providers that you use in your infrastructure code.
It holds the provider blocks
7. locals.tf
locals.tf is used to define local variables and serves as a dedicated place to define and store local values, which are variables specific to your Terraform project.
It has local blocks
8. backend.tf
backend.tf is used for defining the backend configuration of Terraform, which will indicate where the state of your entire infrastructure will be stored.
It has the backend blocks
Advanced File Naming Conventions for Terraform Configurations
As your infrastructure complexity grows, managing multiple resource blocks in a single configuration file can become cumbersome and challenging. Terraform lets you structure your resource blocks into separate files based on logical groupings so as to enhance the readability, maintainability, and scalability of your code. Examples of more advanced naming conventions include:
1. network.tf
Network.tf is used in defining networking infrastructure resources and also turns out as a central place to manage all the network related resources like VPC, subnets, load balancers etc.
2. storage.tf
storage.tf is used for defining the resources of the storage infrastructure and forms a central place for managing all storage-related resources such as buckets, permission settings, access control settings etc.
3. compute.tf
Compute.tf is used for the definition of the resources of the computing infrastructure, and hence is also being used as a location to manage all the computing related resources like virtual machines (EC2) etc.
NOTE:
network.tf, storage.tf, and compute.tf contain the resource blocks.
Directories
A directory is used to organize your
.tf and/or .tf.json files that's considered root module. But the root module can also contain sub-directories, which are considered sub-modules (or child module).
NOTE: Following are the recommended file naming conventions. Terraform, however, will be flexible enough to let you structure your configurations in ways best suited for your projects. The key would be to maintain consistency and organization throughout your codebase for Terraform.
Related Pages
Feedback
Was this page helpful?
.png)
DevOpsResourceHub is designed to enhance your learning experience
in DevOps technologies. While we strive to make our examples
clear and easy to understand, and we regularly update our
content to ensure accuracy, we acknowledge that occasional
mistakes may occur. We encourage continuous learning and welcome
feedback to help us improve.
@Copywrites 2024 All Rights Reserved
