nix-build: add debug_logging option

Author: Mic92

terraform/all-in-one/main.tf

@@ -1,17 +1,19 @@
 module "system-build" {
-  source       = "../nix-build"
-  attribute    = var.nixos_system_attr
-  file         = var.file
-  nix_options  = var.nix_options
-  special_args = var.special_args
+  source        = "../nix-build"
+  attribute     = var.nixos_system_attr
+  debug_logging = var.debug_logging
+  file          = var.file
+  nix_options   = var.nix_options
+  special_args  = var.special_args
 }
 
 module "partitioner-build" {
-  source       = "../nix-build"
-  attribute    = var.nixos_partitioner_attr
-  file         = var.file
-  nix_options  = var.nix_options
-  special_args = var.special_args
+  source        = "../nix-build"
+  attribute     = var.nixos_partitioner_attr
+  debug_logging = var.debug_logging
+  file          = var.file
+  nix_options   = var.nix_options
+  special_args  = var.special_args
 }
 
 locals {

terraform/nix-build/main.tf

@@ -6,10 +6,11 @@ locals {
 data "external" "nix-build" {
   program = ["${path.module}/nix-build.sh"]
   query = {
-    attribute    = var.attribute
-    file         = var.file
-    nix_options  = local.nix_options
-    special_args = jsonencode(var.special_args)
+    attribute     = var.attribute
+    file          = var.file
+    nix_options   = local.nix_options
+    debug_logging = var.debug_logging
+    special_args  = jsonencode(var.special_args)
   }
 }
 output "result" {

terraform/nix-build/nix-build.sh

@@ -1,8 +1,11 @@
 #!/usr/bin/env bash
 set -efu
 
-declare file attribute nix_options special_args
-eval "$(jq -r '@sh "attribute=\(.attribute) file=\(.file) nix_options=\(.nix_options) special_args=\(.special_args)"')"
+declare file attribute nix_options special_args debug_logging
+eval "$(jq -r '@sh "attribute=\(.attribute) file=\(.file) nix_options=\(.nix_options) special_args=\(.special_args) debug_logging=\(.debug_logging)"')"
+if [ "${debug_logging}" = "true" ]; then
+  set -x
+fi
 if [ "${nix_options}" != '{"options":{}}' ]; then
   options=$(echo "${nix_options}" | jq -r '.options | to_entries | map("--option \(.key) \(.value)") | join(" ")')
 else
@@ -41,7 +44,7 @@ else
   # substitute variables into the template
   nix_expr="(builtins.getFlake ''${flake_url}'').${config_path}.extendModules { specialArgs = builtins.fromJSON ''${special_args}''; }"
   # inject `special_args` into nixos config's `specialArgs`
-  
+
   # shellcheck disable=SC2086
   out=$(nix build --no-link --json ${options} --expr "${nix_expr}" "${config_attribute}")
 fi

terraform/nix-build/variables.tf

@@ -20,3 +20,9 @@ variable "special_args" {
   default     = {}
   description = "A map exposed as NixOS's `specialArgs` thru a file."
 }
+
+variable "debug_logging" {
+  type        = bool
+  default     = false
+  description = "Enable debug logging"
+}