Terraform

→ secrets

any variable foo can be replaced by environmeny by naming it TF_VAR_foo

SECRETS ARE ALWAYS STORED IN TERRAFORM STATE

→ Syntax

Use a splat expression:

aws_instance.app.*.id will be a list of all of the IDs of the instances

→ modules

• docs
• module validation
• module object

→ variable validation

• validation argument in var

→ check