Outputs xample

Naming Conventions Example

In this example, we will create a naming convention for outputs in a Terraform codebase. We will use the following naming conventions:

Well-structured output

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output "db_instance_arn" {
2
  # ...
3
}

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output "db_instance_arn" {
2
  # ...
3
}

Avoid Repeating Resource Type

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output "db_instance_arn" {
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  # ...
3
}

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output "db_instance_db_arn" {
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  # ...
3
}

Use Descriptive Names

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output "db_instance_arn" {
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  # ...
3
}

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output "db_instance_id" {
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  # ...
3
}

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output "db_instance_arn_id" {
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  # ...
3
}

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output "db_instance_id_arn" {
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  # ...
3
}

Do Not Use `this` for Outputs

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output "this" {
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  # ...
3
}

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output "output" {
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  # ...
3
}

Use `{resource name}` Prefix

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output "db_instance_arn" {
2
  # ...
3
}

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output "vpc_id" {
2
  # ...
3
}

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output "arn" {
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  # ...
3
}

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output "id" {
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  # ...
3
}

Description for Outputs

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output "db_instance_arn" {
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  description = "The ARN of the RDS instance. Type: string"
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  value       = aws_db_instance.example.arn
4
}

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output "db_arn" {
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  description = "The ARN of the RDS instance. Type: string"
3
  value       = aws_db_instance.example.arn
4
}

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output "db_instance_arn" {
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  description = "The ARN of the RDS instance"
3
  value       = aws_db_instance.example.arn
4
}

Leverage Output Argument Standards

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output "db_instance_arn" {
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  description = "The ARN of the RDS instance. Type: string"
3
  value       = aws_db_instance.example.arn
4
}

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output "db_arn" {
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  description = "The ARN of the RDS instance. Type: string"
3
  value       = aws_db_instance.example.arn
4
}

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output "db_instance_arn" {
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  description = "The ARN of the RDS instance"
3
  value       = aws_db_instance.example.arn
4
}

Use the `try`, `element` and `concat` functions to get the output value

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output "db_instance_arn" {
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  description = "The ARN of the RDS instance. Type: string"
3
  value       = try(element(concat(aws_db_instance.example.*.arn, list("")), 0), "")
4
}

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output "db_instance_custom_wrapper_arn" {
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  description = "The ARN of the RDS instance. Type: string"
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  value       = try(module.example.*.db_instance_arn, "")
4
}

Conclusion

In this example, we have demonstrated how to create a naming convention for outputs in a Terraform codebase. By following these conventions, you can ensure that your outputs are well-structured, descriptive, and easy to understand. This will make it easier for you and your team to work with the codebase and maintain consistency across your projects.