The terraform validate command is a powerful tool in Terraform that helps ensure that your Terraform configuration files are syntactically valid and adhere to the Terraform language’s expected format.
It helps developers identify and correct syntax errors, ensure consistency across different configurations, provide quick feedback on issues, and ensure that all Terraform configurations adhere to best practices.
Let’s see common errors identified by “terraform validate” command:
a) Invalid HCL syntax (e.g. missing equal sign or quotes)
Error: Unterminated template string
│
│ on main.tf line 2, in module "vpc":
│ 2: source = "./modules/vpc
│ 3: saran = var.newinput
│
│ No closing marker was found for the string.b) Invalid HCL references (e.g. variable name or attribute which doesn’t exist)
Error: Reference to undeclared input variable
│
│ on main.tf line 3, in module "vpc":
│ 3: saran = var.newinput
│
│ An input variable with the name
│ "newinput" has not been declared. Did
│ you mean "newinput1"?c) The same module declared multiple times as shown below; The same is applicable for multiple same providers and same resources declared multiple times
│ Error: Duplicate module call
│ on main.tf line 6:
│ 6: module "vpc" {
│
│ A module call named "vpc" was already
│ defined at main.tf:1,1-13. Module calls
│ must have unique names within a module.d) Invalid module name
│ Error: Module not installed
│ 6: module "vpc1" {
│
│ This module is not yet installed. Run
│ "terraform init" to install all modules
│ required by this configuration.
╵e) Interpolation used in places where it’s unsupported (e.g. variable, depends_on, module.source, provider)
Error: Unsupported argument
│
│ on variables.tf line 3, in variable "newinput":
│ 3: depends_on = [
│
│ An argument named "depends_on" is not expected here.
╵f) Missing value for a variable
Error: expected cidr_block to contain a valid Value, got: with err: invalid CIDR address:
│
│ with module.vpc.aws_vpc.saran-vpc,
│ on modules\vpc\vpc.tf line 2, in resource "aws_vpc" "saran-vpc":
│ 2: cidr_block = ""Note: The validation is not applicable for variables declared through -var flag, -var-file=saran.vars flag, TF_VAR_foo environment variable, terraform.tfvars, or default value in the configuration.
In summary, some of the uses and benefits of the terraform validate command are:
- Syntax Checking: The terraform validate command checks the syntax of your Terraform configuration files to ensure they comply with the expected format. It will identify syntax errors, invalid arguments, and other issues that could cause errors or prevent the Terraform code from working as intended.
- Quick Feedback: terraform validate provides quick feedback on any syntax errors or invalid configurations, enabling developers to identify and correct issues early in the development cycle, reducing the likelihood of issues propagating to production.
- Pre-deployment checks: terraform validate can be integrated into continuous integration/continuous delivery (CI/CD) pipelines, providing pre-deployment checks that ensure any code changes to the Terraform codebase adhere to best practices, syntax requirements, and naming conventions.
- Consistency: Using terraform validate ensures that all Terraform configurations in your project adhere to the same best practices, syntax requirements, and naming conventions, reducing the likelihood of inconsistencies across different Terraform configurations.
In summary, the terraform validate command is an essential tool for anyone working with Terraform.
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Terraform validate validates that your infrastructure matches the Terraform state file.
- A. True
- B. False
Terraform validate validates the syntax of Terraform files.
- A. True
- B. False