Conditions

Use a condition attribute to create resources only when specific conditions are met. This is the function-hcl equivalent of Terraform’s count = var.create ? 1 : 0.

On a Resource

resource s3_acl {
  condition = try(req.composite.spec.parameters.createAcls, true)

  body = {
    # ...
  }
}

The condition expression must evaluate to a boolean value. If the value is false, the resource is skipped entirely.

On a Resource Collection

When applied to a resources block, the condition controls the entire collection. To filter individual elements, filter the collection that for_each iterates over instead.

resources s3_acls {
  condition = req.composite.spec.parameters.createAcls

  for_each = req.composite.spec.parameters.suffixes
  template {
    body = { ... }
  }
}

On a Group

A condition on a group skips all resources in the group:

group {
  condition = req.composite.spec.parameters.createMoreBuckets

  resource additional-bucket-one { ... }
  resource additional-bucket-two { ... }
}

Incomplete Conditions

Unlike resource bodies, where incomplete values cause deferral, an incomplete condition value is treated as false. Use try and can if the condition depends on values that might not exist yet:

resource my-resource {
  # If createFoo doesn't exist in the parameters, default to true
  condition = try(req.composite.spec.parameters.createFoo, true)

  body = { ... }
}