remove duplicate paths in layering

This is a 🐞 bug fix.

[ ] I've added tests (if it's a bug, feature or enhancement)
[ ] I've adjusted the documentation (if it's a feature or enhancement)
[X] The test suite passes (run bundle exec rspec to verify this)

Summary

Removes duplicate entries from layering paths that occur when you add a layer name mapping that matches TS_ENV.

Eventually this leads to tfvar files with duplicated variables - 1-sbx.auto.tfvar 2-sbx.auto.tfvar.

Context

This really extended from my improper use of layer name mappings. It was a simple fix once I tracked it down (in the config), but thought it could warrant a fix anyway to prevent user frustration in the future.

How to Test

TS_SHOW_ALL_LAYERS=1 was showing duplicate entries when running TS_ENV=sbx terraspace build mystack. See output below.

    ....
    config/terraform/tfvars/base.tfvars
    # this is duplicated below
    config/terraform/tfvars/sbx.tfvars
    config/terraform/tfvars/sbx/base.tfvars
    config/terraform/tfvars/sbx/sbx.tfvars
    config/terraform/tfvars/us-east-1.tfvars
    config/terraform/tfvars/us-east-1/base.tfvars
    config/terraform/tfvars/us-east-1/sbx.tfvars
    config/terraform/tfvars/us-east-1/sbx/base.tfvars
    config/terraform/tfvars/us-east-1/sbx/sbx.tfvars
    # duplication starts here of `sbx`
    config/terraform/tfvars/sbx.tfvars
    config/terraform/tfvars/sbx/base.tfvars
    ...

I tracked this back to namespace mappings where I had added to config/app.rb, see below.

Terraspace.configure do |config|
  config.layering.names = {
    "123456789123" => "dev",
    "123456789124" => "prd",
    "123456789125" => "stg",  <--- changing this to acct-stg prevents the duplicates
    "123456789126" => "sbx",
  }
end

Please feel free to reject this fix if you feel it is not necessary due to the improper use of mappings.

Took some time to think about this one. Here's some review:

When Friendly Account Name Does Not Match TS_ENV

config/app.rb

Terraspace.configure do |config|
  config.layering.names = {
    "111111111111" => "dev-account",
  }
  config.layering.mode = "namespace" # simple, namespace, or provider
end

$ export TS_SHOW_ALL_LAYERS=1
$ terraspace build demo 2>&1 | grep config
    config/terraform/tfvars/base.tfvars
    config/terraform/tfvars/dev.tfvars
    config/terraform/tfvars/us-west-2.tfvars
    config/terraform/tfvars/us-west-2/base.tfvars
    config/terraform/tfvars/us-west-2/dev.tfvars
    config/terraform/tfvars/dev-account.tfvars # <= ALL OK
    config/terraform/tfvars/dev-account/base.tfvars
    config/terraform/tfvars/dev-account/dev.tfvars
    config/terraform/tfvars/dev-account/us-west-2.tfvars
    config/terraform/tfvars/dev-account/us-west-2/base.tfvars
    config/terraform/tfvars/dev-account/us-west-2/dev.tfvars
$

When Friendly Account Name Matches TS_ENV

config/app.rb

Terraspace.configure do |config|
  config.layering.names = {
    "111111111111" => "dev",
  }
  config.layering.mode = "namespace" # simple, namespace, or provider
end

$ export TS_SHOW_ALL_LAYERS=1
$ terraspace build demo 2>&1 | grep config
    config/terraform/tfvars/base.tfvars
    config/terraform/tfvars/dev.tfvars
    config/terraform/tfvars/us-west-2.tfvars
    config/terraform/tfvars/us-west-2/base.tfvars
    config/terraform/tfvars/us-west-2/dev.tfvars
    config/terraform/tfvars/dev.tfvars # <= DUPLICATED
    config/terraform/tfvars/dev/base.tfvars
    config/terraform/tfvars/dev/dev.tfvars
    config/terraform/tfvars/dev/us-west-2.tfvars
    config/terraform/tfvars/dev/us-west-2/base.tfvars
    config/terraform/tfvars/dev/us-west-2/dev.tfvars
$

It was a bit of a struggle. Think it's better to remove the duplicated layer like you've done. Think the namespace layer is less used and so it's more expected that config/terraform/tfvars/dev.tfvars essentially takes higher precedence. Thanks for the PR and explanation.

With the Change

The second config/terraform/tfvars/dev/base.tfvars is removed.

$ export TS_SHOW_ALL_LAYERS=1
$ terraspace build demo 2>&1 | grep config
    config/terraform/tfvars/base.tfvars
    config/terraform/tfvars/dev.tfvars
    config/terraform/tfvars/us-west-2.tfvars
    config/terraform/tfvars/us-west-2/base.tfvars
    config/terraform/tfvars/us-west-2/dev.tfvars
    config/terraform/tfvars/dev/base.tfvars
    config/terraform/tfvars/dev/dev.tfvars
    config/terraform/tfvars/dev/us-west-2.tfvars
    config/terraform/tfvars/dev/us-west-2/base.tfvars
    config/terraform/tfvars/dev/us-west-2/dev.tfvars
$

Also updated the docs with a note https://terraspace.cloud/docs/layering/friendly-names/ Also note, in Terraspace 2.0 layering was tweaked. It was simplified.

boltops-tools / terraspace