feat: Add custom subnet names (#816)

Co-authored-by: Anton Babenko <anton@antonbabenko.com>

.pre-commit-config.yaml

 repos:
   - repo: https://github.com/antonbabenko/pre-commit-terraform
-    rev: v1.75.0
+    rev: v1.76.0
     hooks:
       - id: terraform_fmt
       - id: terraform_validate

README.md

@@ -380,6 +380,7 @@ No modules.
 | <a name="input_database_subnet_group_name"></a> [database\_subnet\_group\_name](#input\_database\_subnet\_group\_name) | Name of database subnet group | `string` | `null` | no |
 | <a name="input_database_subnet_group_tags"></a> [database\_subnet\_group\_tags](#input\_database\_subnet\_group\_tags) | Additional tags for the database subnet group | `map(string)` | `{}` | no |
 | <a name="input_database_subnet_ipv6_prefixes"></a> [database\_subnet\_ipv6\_prefixes](#input\_database\_subnet\_ipv6\_prefixes) | Assigns IPv6 database subnet id based on the Amazon provided /56 prefix base 10 integer (0-256). Must be of equal length to the corresponding IPv4 subnet list | `list(string)` | `[]` | no |
+| <a name="input_database_subnet_names"></a> [database\_subnet\_names](#input\_database\_subnet\_names) | Explicit values to use in the Name tag on database subnets. If empty, Name tags are generated. | `list(string)` | `[]` | no |
 | <a name="input_database_subnet_suffix"></a> [database\_subnet\_suffix](#input\_database\_subnet\_suffix) | Suffix to append to database subnets name | `string` | `"db"` | no |
 | <a name="input_database_subnet_tags"></a> [database\_subnet\_tags](#input\_database\_subnet\_tags) | Additional tags for the database subnets | `map(string)` | `{}` | no |
 | <a name="input_database_subnets"></a> [database\_subnets](#input\_database\_subnets) | A list of database subnets | `list(string)` | `[]` | no |
@@ -415,6 +416,7 @@ No modules.
 | <a name="input_elasticache_subnet_group_name"></a> [elasticache\_subnet\_group\_name](#input\_elasticache\_subnet\_group\_name) | Name of elasticache subnet group | `string` | `null` | no |
 | <a name="input_elasticache_subnet_group_tags"></a> [elasticache\_subnet\_group\_tags](#input\_elasticache\_subnet\_group\_tags) | Additional tags for the elasticache subnet group | `map(string)` | `{}` | no |
 | <a name="input_elasticache_subnet_ipv6_prefixes"></a> [elasticache\_subnet\_ipv6\_prefixes](#input\_elasticache\_subnet\_ipv6\_prefixes) | Assigns IPv6 elasticache subnet id based on the Amazon provided /56 prefix base 10 integer (0-256). Must be of equal length to the corresponding IPv4 subnet list | `list(string)` | `[]` | no |
+| <a name="input_elasticache_subnet_names"></a> [elasticache\_subnet\_names](#input\_elasticache\_subnet\_names) | Explicit values to use in the Name tag on elasticache subnets. If empty, Name tags are generated. | `list(string)` | `[]` | no |
 | <a name="input_elasticache_subnet_suffix"></a> [elasticache\_subnet\_suffix](#input\_elasticache\_subnet\_suffix) | Suffix to append to elasticache subnets name | `string` | `"elasticache"` | no |
 | <a name="input_elasticache_subnet_tags"></a> [elasticache\_subnet\_tags](#input\_elasticache\_subnet\_tags) | Additional tags for the elasticache subnets | `map(string)` | `{}` | no |
 | <a name="input_elasticache_subnets"></a> [elasticache\_subnets](#input\_elasticache\_subnets) | A list of elasticache subnets | `list(string)` | `[]` | no |
@@ -451,6 +453,7 @@ No modules.
 | <a name="input_intra_route_table_tags"></a> [intra\_route\_table\_tags](#input\_intra\_route\_table\_tags) | Additional tags for the intra route tables | `map(string)` | `{}` | no |
 | <a name="input_intra_subnet_assign_ipv6_address_on_creation"></a> [intra\_subnet\_assign\_ipv6\_address\_on\_creation](#input\_intra\_subnet\_assign\_ipv6\_address\_on\_creation) | Assign IPv6 address on intra subnet, must be disabled to change IPv6 CIDRs. This is the IPv6 equivalent of map\_public\_ip\_on\_launch | `bool` | `null` | no |
 | <a name="input_intra_subnet_ipv6_prefixes"></a> [intra\_subnet\_ipv6\_prefixes](#input\_intra\_subnet\_ipv6\_prefixes) | Assigns IPv6 intra subnet id based on the Amazon provided /56 prefix base 10 integer (0-256). Must be of equal length to the corresponding IPv4 subnet list | `list(string)` | `[]` | no |
+| <a name="input_intra_subnet_names"></a> [intra\_subnet\_names](#input\_intra\_subnet\_names) | Explicit values to use in the Name tag on intra subnets. If empty, Name tags are generated. | `list(string)` | `[]` | no |
 | <a name="input_intra_subnet_suffix"></a> [intra\_subnet\_suffix](#input\_intra\_subnet\_suffix) | Suffix to append to intra subnets name | `string` | `"intra"` | no |
 | <a name="input_intra_subnet_tags"></a> [intra\_subnet\_tags](#input\_intra\_subnet\_tags) | Additional tags for the intra subnets | `map(string)` | `{}` | no |
 | <a name="input_intra_subnets"></a> [intra\_subnets](#input\_intra\_subnets) | A list of intra subnets | `list(string)` | `[]` | no |
@@ -477,6 +480,7 @@ No modules.
 | <a name="input_outpost_outbound_acl_rules"></a> [outpost\_outbound\_acl\_rules](#input\_outpost\_outbound\_acl\_rules) | Outpost subnets outbound network ACLs | `list(map(string))` | <pre>[<br>  {<br>    "cidr_block": "0.0.0.0/0",<br>    "from_port": 0,<br>    "protocol": "-1",<br>    "rule_action": "allow",<br>    "rule_number": 100,<br>    "to_port": 0<br>  }<br>]</pre> | no |
 | <a name="input_outpost_subnet_assign_ipv6_address_on_creation"></a> [outpost\_subnet\_assign\_ipv6\_address\_on\_creation](#input\_outpost\_subnet\_assign\_ipv6\_address\_on\_creation) | Assign IPv6 address on outpost subnet, must be disabled to change IPv6 CIDRs. This is the IPv6 equivalent of map\_public\_ip\_on\_launch | `bool` | `null` | no |
 | <a name="input_outpost_subnet_ipv6_prefixes"></a> [outpost\_subnet\_ipv6\_prefixes](#input\_outpost\_subnet\_ipv6\_prefixes) | Assigns IPv6 outpost subnet id based on the Amazon provided /56 prefix base 10 integer (0-256). Must be of equal length to the corresponding IPv4 subnet list | `list(string)` | `[]` | no |
+| <a name="input_outpost_subnet_names"></a> [outpost\_subnet\_names](#input\_outpost\_subnet\_names) | Explicit values to use in the Name tag on outpost subnets. If empty, Name tags are generated. | `list(string)` | `[]` | no |
 | <a name="input_outpost_subnet_suffix"></a> [outpost\_subnet\_suffix](#input\_outpost\_subnet\_suffix) | Suffix to append to outpost subnets name | `string` | `"outpost"` | no |
 | <a name="input_outpost_subnet_tags"></a> [outpost\_subnet\_tags](#input\_outpost\_subnet\_tags) | Additional tags for the outpost subnets | `map(string)` | `{}` | no |
 | <a name="input_outpost_subnets"></a> [outpost\_subnets](#input\_outpost\_subnets) | A list of outpost subnets inside the VPC | `list(string)` | `[]` | no |
@@ -487,6 +491,7 @@ No modules.
 | <a name="input_private_route_table_tags"></a> [private\_route\_table\_tags](#input\_private\_route\_table\_tags) | Additional tags for the private route tables | `map(string)` | `{}` | no |
 | <a name="input_private_subnet_assign_ipv6_address_on_creation"></a> [private\_subnet\_assign\_ipv6\_address\_on\_creation](#input\_private\_subnet\_assign\_ipv6\_address\_on\_creation) | Assign IPv6 address on private subnet, must be disabled to change IPv6 CIDRs. This is the IPv6 equivalent of map\_public\_ip\_on\_launch | `bool` | `null` | no |
 | <a name="input_private_subnet_ipv6_prefixes"></a> [private\_subnet\_ipv6\_prefixes](#input\_private\_subnet\_ipv6\_prefixes) | Assigns IPv6 private subnet id based on the Amazon provided /56 prefix base 10 integer (0-256). Must be of equal length to the corresponding IPv4 subnet list | `list(string)` | `[]` | no |
+| <a name="input_private_subnet_names"></a> [private\_subnet\_names](#input\_private\_subnet\_names) | Explicit values to use in the Name tag on private subnets. If empty, Name tags are generated. | `list(string)` | `[]` | no |
 | <a name="input_private_subnet_suffix"></a> [private\_subnet\_suffix](#input\_private\_subnet\_suffix) | Suffix to append to private subnets name | `string` | `"private"` | no |
 | <a name="input_private_subnet_tags"></a> [private\_subnet\_tags](#input\_private\_subnet\_tags) | Additional tags for the private subnets | `map(string)` | `{}` | no |
 | <a name="input_private_subnets"></a> [private\_subnets](#input\_private\_subnets) | A list of private subnets inside the VPC | `list(string)` | `[]` | no |
@@ -500,6 +505,7 @@ No modules.
 | <a name="input_public_route_table_tags"></a> [public\_route\_table\_tags](#input\_public\_route\_table\_tags) | Additional tags for the public route tables | `map(string)` | `{}` | no |
 | <a name="input_public_subnet_assign_ipv6_address_on_creation"></a> [public\_subnet\_assign\_ipv6\_address\_on\_creation](#input\_public\_subnet\_assign\_ipv6\_address\_on\_creation) | Assign IPv6 address on public subnet, must be disabled to change IPv6 CIDRs. This is the IPv6 equivalent of map\_public\_ip\_on\_launch | `bool` | `null` | no |
 | <a name="input_public_subnet_ipv6_prefixes"></a> [public\_subnet\_ipv6\_prefixes](#input\_public\_subnet\_ipv6\_prefixes) | Assigns IPv6 public subnet id based on the Amazon provided /56 prefix base 10 integer (0-256). Must be of equal length to the corresponding IPv4 subnet list | `list(string)` | `[]` | no |
+| <a name="input_public_subnet_names"></a> [public\_subnet\_names](#input\_public\_subnet\_names) | Explicit values to use in the Name tag on public subnets. If empty, Name tags are generated. | `list(string)` | `[]` | no |
 | <a name="input_public_subnet_suffix"></a> [public\_subnet\_suffix](#input\_public\_subnet\_suffix) | Suffix to append to public subnets name | `string` | `"public"` | no |
 | <a name="input_public_subnet_tags"></a> [public\_subnet\_tags](#input\_public\_subnet\_tags) | Additional tags for the public subnets | `map(string)` | `{}` | no |
 | <a name="input_public_subnets"></a> [public\_subnets](#input\_public\_subnets) | A list of public subnets inside the VPC | `list(string)` | `[]` | no |
@@ -513,6 +519,7 @@ No modules.
 | <a name="input_redshift_subnet_group_name"></a> [redshift\_subnet\_group\_name](#input\_redshift\_subnet\_group\_name) | Name of redshift subnet group | `string` | `null` | no |
 | <a name="input_redshift_subnet_group_tags"></a> [redshift\_subnet\_group\_tags](#input\_redshift\_subnet\_group\_tags) | Additional tags for the redshift subnet group | `map(string)` | `{}` | no |
 | <a name="input_redshift_subnet_ipv6_prefixes"></a> [redshift\_subnet\_ipv6\_prefixes](#input\_redshift\_subnet\_ipv6\_prefixes) | Assigns IPv6 redshift subnet id based on the Amazon provided /56 prefix base 10 integer (0-256). Must be of equal length to the corresponding IPv4 subnet list | `list(string)` | `[]` | no |
+| <a name="input_redshift_subnet_names"></a> [redshift\_subnet\_names](#input\_redshift\_subnet\_names) | Explicit values to use in the Name tag on redshift subnets. If empty, Name tags are generated. | `list(string)` | `[]` | no |
 | <a name="input_redshift_subnet_suffix"></a> [redshift\_subnet\_suffix](#input\_redshift\_subnet\_suffix) | Suffix to append to redshift subnets name | `string` | `"redshift"` | no |
 | <a name="input_redshift_subnet_tags"></a> [redshift\_subnet\_tags](#input\_redshift\_subnet\_tags) | Additional tags for the redshift subnets | `map(string)` | `{}` | no |
 | <a name="input_redshift_subnets"></a> [redshift\_subnets](#input\_redshift\_subnets) | A list of redshift subnets | `list(string)` | `[]` | no |

examples/complete-vpc/main.tf

@@ -31,6 +31,13 @@ module "vpc" {
   redshift_subnets    = ["10.0.41.0/24", "10.0.42.0/24", "10.0.43.0/24"]
   intra_subnets       = ["10.0.51.0/24", "10.0.52.0/24", "10.0.53.0/24"]
 
+  private_subnet_names = ["Private Subnet One", "Private Subnet Two"]
+  # public_subnet_names omitted to show default name generation for all three subnets
+  database_subnet_names    = ["DB Subnet One"]
+  elasticache_subnet_names = ["Elasticache Subnet One", "Elasticache Subnet Two"]
+  redshift_subnet_names    = ["Redshift Subnet One", "Redshift Subnet Two", "Redshift Subnet Three"]
+  intra_subnet_names       = []
+
   create_database_subnet_group = false
 
   manage_default_network_acl = true

main.tf

@@ -370,9 +370,9 @@ resource "aws_subnet" "public" {
 
   tags = merge(
     {
-      "Name" = format(
-        "${var.name}-${var.public_subnet_suffix}-%s",
-        element(var.azs, count.index),
+      Name = try(
+        var.public_subnet_names[count.index],
+        format("${var.name}-${var.public_subnet_suffix}-%s", element(var.azs, count.index))
       )
     },
     var.tags,
@@ -397,9 +397,9 @@ resource "aws_subnet" "private" {
 
   tags = merge(
     {
-      "Name" = format(
-        "${var.name}-${var.private_subnet_suffix}-%s",
-        element(var.azs, count.index),
+      Name = try(
+        var.private_subnet_names[count.index],
+        format("${var.name}-${var.private_subnet_suffix}-%s", element(var.azs, count.index))
       )
     },
     var.tags,
@@ -425,9 +425,9 @@ resource "aws_subnet" "outpost" {
 
   tags = merge(
     {
-      "Name" = format(
-        "${var.name}-${var.outpost_subnet_suffix}-%s",
-        var.outpost_az,
+      Name = try(
+        var.outpost_subnet_names[count.index],
+        format("${var.name}-${var.outpost_subnet_suffix}-%s", var.outpost_az)
       )
     },
     var.tags,
@@ -452,9 +452,9 @@ resource "aws_subnet" "database" {
 
   tags = merge(
     {
-      "Name" = format(
-        "${var.name}-${var.database_subnet_suffix}-%s",
-        element(var.azs, count.index),
+      Name = try(
+        var.database_subnet_names[count.index],
+        format("${var.name}-${var.database_subnet_suffix}-%s", element(var.azs, count.index), )
       )
     },
     var.tags,
@@ -495,9 +495,9 @@ resource "aws_subnet" "redshift" {
 
   tags = merge(
     {
-      "Name" = format(
-        "${var.name}-${var.redshift_subnet_suffix}-%s",
-        element(var.azs, count.index),
+      Name = try(
+        var.redshift_subnet_names[count.index],
+        format("${var.name}-${var.redshift_subnet_suffix}-%s", element(var.azs, count.index))
       )
     },
     var.tags,
@@ -536,9 +536,9 @@ resource "aws_subnet" "elasticache" {
 
   tags = merge(
     {
-      "Name" = format(
-        "${var.name}-${var.elasticache_subnet_suffix}-%s",
-        element(var.azs, count.index),
+      Name = try(
+        var.elasticache_subnet_names[count.index],
+        format("${var.name}-${var.elasticache_subnet_suffix}-%s", element(var.azs, count.index))
       )
     },
     var.tags,
@@ -577,9 +577,9 @@ resource "aws_subnet" "intra" {
 
   tags = merge(
     {
-      "Name" = format(
-        "${var.name}-${var.intra_subnet_suffix}-%s",
-        element(var.azs, count.index),
+      Name = try(
+        var.intra_subnet_names[count.index],
+        format("${var.name}-${var.intra_subnet_suffix}-%s", element(var.azs, count.index))
       )
     },
     var.tags,

variables.tf

@@ -136,6 +136,48 @@ variable "private_subnet_suffix" {
   default     = "private"
 }
 
+variable "public_subnet_names" {
+  description = "Explicit values to use in the Name tag on public subnets. If empty, Name tags are generated."
+  type        = list(string)
+  default     = []
+}
+
+variable "private_subnet_names" {
+  description = "Explicit values to use in the Name tag on private subnets. If empty, Name tags are generated."
+  type        = list(string)
+  default     = []
+}
+
+variable "outpost_subnet_names" {
+  description = "Explicit values to use in the Name tag on outpost subnets. If empty, Name tags are generated."
+  type        = list(string)
+  default     = []
+}
+
+variable "intra_subnet_names" {
+  description = "Explicit values to use in the Name tag on intra subnets. If empty, Name tags are generated."
+  type        = list(string)
+  default     = []
+}
+
+variable "database_subnet_names" {
+  description = "Explicit values to use in the Name tag on database subnets. If empty, Name tags are generated."
+  type        = list(string)
+  default     = []
+}
+
+variable "redshift_subnet_names" {
+  description = "Explicit values to use in the Name tag on redshift subnets. If empty, Name tags are generated."
+  type        = list(string)
+  default     = []
+}
+
+variable "elasticache_subnet_names" {
+  description = "Explicit values to use in the Name tag on elasticache subnets. If empty, Name tags are generated."
+  type        = list(string)
+  default     = []
+}
+
 variable "outpost_subnet_suffix" {
   description = "Suffix to append to outpost subnets name"
   type        = string