Terraform error not correctly displayed when using bbl in debug mode

[jochenehret]

Hi bbl developers,

when we run bbl in debug mode and a Terraform subcommand fails, the output is not correctly formatted. We see a long list of numbers which should be converted into a string. Example:

bbl --debug up --lb-type=cf --lb-cert=/tmp/bbl-cert --lb-key=/tmp/bbl-key (...)

╷
│ Error: attaching policy arn:aws:iam::537913301405:policy/perf-test-rails_bosh_policy to IAM Role perf-test-rails_bosh_role: NoSuchEntity: The role with name perf-test-rails_bosh_role cannot be found.
│ 	status code: 404, request id: 132f6022-c5b9-46b5-a117-2d0c4e0c6ee8
│ 
│   with aws_iam_role_policy_attachment.bosh[0],
│   on bbl-template.tf line 653, in resource "aws_iam_role_policy_attachment" "bosh":
│  653: resource "aws_iam_role_policy_attachment" "bosh" {
│ 
╵
(...)
Executor apply: command execution failed got: exit status 1 stderr:
 &{[%!s(*os.File=&{0xc000118120}) %!s(*bytes.Buffer=&{[10 27 91 48 109 27 91 49 109 73 110 105 116 105 97 108 105 122 105 110 103 32 116 104 101 (...)

I guess that somewhere here a (string) conversion is missing:

bosh-bootloader/terraform/cli.go

Line 44 in 1e92232

return fmt.Errorf("command execution failed got: %s stderr:\n %s", err, c.errorBuffer)

I haven't found a test that provokes an error and validates the output conversion.

Thanks for handling this issue!

[ramonskie]

well before it would swallow all errors :)
as noted in this commit b386086
but when i have some time i will take a look