Add fork_from to repository config

Express a fork as an optional fork_from key on the repository yaml, so a
forked repo is declared the same way as any other repo.

- add fork_from "<owner>/<repo>" to the repository module and object type
- create gitea_fork instead of gitea_repository when fork_from is set
- validate the source repo name matches the config file name, since a fork
  inherits the source name
- move gitea_repository.this to index 0 for the count refactor
- index existing repository import targets to match

modules/gitea_instance/imports.tf

@@ -4,167 +4,167 @@ import {
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/puppet-prod"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/puppet-prod"].gitea_repository.this[0]
   id = "2"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/puppet-r10k"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/puppet-r10k"].gitea_repository.this[0]
   id = "3"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/rpmbuild-gonic"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/rpmbuild-gonic"].gitea_repository.this[0]
   id = "23"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/docker-almalinux-base"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/docker-almalinux-base"].gitea_repository.this[0]
   id = "24"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/rpmbuild-internal-ca-certificates"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/rpmbuild-internal-ca-certificates"].gitea_repository.this[0]
   id = "27"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/rpmbuild-template"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/rpmbuild-template"].gitea_repository.this[0]
   id = "29"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/rpmbuild-jellyfin-web"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/rpmbuild-jellyfin-web"].gitea_repository.this[0]
   id = "31"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/rpmbuild-proxlb"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/rpmbuild-proxlb"].gitea_repository.this[0]
   id = "33"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/docker-almalinux-buildrunner"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/docker-almalinux-buildrunner"].gitea_repository.this[0]
   id = "36"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/docker-template"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/docker-template"].gitea_repository.this[0]
   id = "38"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/terraform-vault"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/terraform-vault"].gitea_repository.this[0]
   id = "39"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/docker-almalinux-jupyterinstance"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/docker-almalinux-jupyterinstance"].gitea_repository.this[0]
   id = "40"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/rpmbuilder"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/rpmbuilder"].gitea_repository.this[0]
   id = "41"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/docker-almalinux-runnerdnd"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/docker-almalinux-runnerdnd"].gitea_repository.this[0]
   id = "43"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/initbuilder"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/initbuilder"].gitea_repository.this[0]
   id = "47"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/puppetapi"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/puppetapi"].gitea_repository.this[0]
   id = "50"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/terraform-nomad"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/terraform-nomad"].gitea_repository.this[0]
   id = "53"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/packer-images"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/packer-images"].gitea_repository.this[0]
   id = "59"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/app-sudaporn-research-normalised"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/app-sudaporn-research-normalised"].gitea_repository.this[0]
   id = "60"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/app-sudaporn-research-individual"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/app-sudaporn-research-individual"].gitea_repository.this[0]
   id = "63"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/terraform-incus"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/terraform-incus"].gitea_repository.this[0]
   id = "66"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/artifactapi"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/artifactapi"].gitea_repository.this[0]
   id = "67"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/argocd-apps"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/argocd-apps"].gitea_repository.this[0]
   id = "100"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/certmanager"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/certmanager"].gitea_repository.this[0]
   id = "101"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/node-lookup"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/node-lookup"].gitea_repository.this[0]
   id = "102"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/container-devcompute"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/container-devcompute"].gitea_repository.this[0]
   id = "135"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/streamstack"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/streamstack"].gitea_repository.this[0]
   id = "136"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/terraform-provider-artifactapi"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/terraform-provider-artifactapi"].gitea_repository.this[0]
   id = "137"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/forgebot"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/forgebot"].gitea_repository.this[0]
   id = "139"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/forgebot-skills"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/forgebot-skills"].gitea_repository.this[0]
   id = "140"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/container-agent-base"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/container-agent-base"].gitea_repository.this[0]
   id = "141"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/container-agent-dev"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/container-agent-dev"].gitea_repository.this[0]
   id = "142"
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/container-agent-infra"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/container-agent-infra"].gitea_repository.this[0]
   id = "143"
 }
 
@@ -199,7 +199,7 @@ import {
 }
 
 import {
-  to = module.repository["git.unkin.net/unkin/terraform-git"].gitea_repository.this
+  to = module.repository["git.unkin.net/unkin/terraform-git"].gitea_repository.this[0]
   id = "144"
 }
 

modules/gitea_instance/main.tf

@@ -19,6 +19,7 @@ module "repository" {
 
   name                    = each.value.name
   organisation            = each.value.organisation
+  fork_from               = each.value.fork_from
   description             = each.value.description
   private                 = each.value.private
   default_branch          = each.value.default_branch

modules/gitea_instance/modules/repository/main.tf

@@ -1,4 +1,10 @@
+locals {
+  fork_source = var.fork_from == null ? null : split("/", var.fork_from)
+}
+
 resource "gitea_repository" "this" {
+  count = var.fork_from == null ? 1 : 0
+
   username                = var.organisation
   name                    = var.name
   description             = var.description
@@ -33,3 +39,16 @@ resource "gitea_repository" "this" {
     ignore_changes = [migration_mirror_interval]
   }
 }
+
+moved {
+  from = gitea_repository.this
+  to   = gitea_repository.this[0]
+}
+
+resource "gitea_fork" "this" {
+  count = var.fork_from == null ? 0 : 1
+
+  owner        = local.fork_source[0]
+  repo         = local.fork_source[1]
+  organization = var.organisation
+}

modules/gitea_instance/modules/repository/outputs.tf

@@ -1,3 +1,3 @@
 output "id" {
-  value = gitea_repository.this.id
+  value = one(concat(gitea_repository.this[*].id, gitea_fork.this[*].id))
 }

modules/gitea_instance/modules/repository/variables.tf

@@ -6,6 +6,22 @@ variable "organisation" {
   type = string
 }
 
+variable "fork_from" {
+  description = "Source repository to fork, as \"<owner>/<repo>\". When set, a fork is created instead of a new repository."
+  type        = string
+  default     = null
+
+  validation {
+    condition     = var.fork_from == null || can(regex("^[^/]+/[^/]+$", var.fork_from))
+    error_message = "fork_from must be \"<owner>/<repo>\"."
+  }
+
+  validation {
+    condition     = var.fork_from == null || try(split("/", var.fork_from)[1], null) == var.name
+    error_message = "fork_from source repository must be named \"${var.name}\": a fork inherits the source name, so it cannot differ from the config file name."
+  }
+}
+
 variable "description" {
   type    = string
   default = null

modules/gitea_instance/variables.tf

@@ -17,6 +17,7 @@ variable "repository" {
   type = map(object({
     name                    = string
     organisation            = string
+    fork_from               = optional(string)
     description             = optional(string)
     private                 = optional(bool)
     default_branch          = optional(string)