6 files changed, 108 insertions, 21 deletions
diff --git a/nixos/modules/services/misc/atuin.nix b/nixos/modules/services/misc/atuin.nix
index 8d2c1b5242f..2d6ffc510ce 100644
--- a/nixos/modules/services/misc/atuin.nix
+++ b/nixos/modules/services/misc/atuin.nix
@@ -73,9 +73,7 @@ in
       enable = true;
       ensureUsers = [{
         name = "atuin";
-        ensurePermissions = {
-          "DATABASE atuin" = "ALL PRIVILEGES";
-        };
+        ensureDBOwnership = true;
       }];
       ensureDatabases = [ "atuin" ];
     };
diff --git a/nixos/modules/services/misc/forgejo.md b/nixos/modules/services/misc/forgejo.md
new file mode 100644
index 00000000000..3df8bc20976
--- /dev/null
+++ b/nixos/modules/services/misc/forgejo.md
@@ -0,0 +1,79 @@
+# Forgejo {#module-forgejo}
+
+Forgejo is a soft-fork of gitea, with strong community focus, as well
+as on self-hosting and federation. [Codeberg](https://codeberg.org) is
+deployed from it.
+
+See [upstream docs](https://forgejo.org/docs/latest/).
+
+The method of choice for running forgejo is using [`services.forgejo`](#opt-services.forgejo.enable).
+
+::: {.warning}
+Running forgejo using `services.gitea.package = pkgs.forgejo` is no longer
+recommended.
+If you experience issues with your instance using `services.gitea`,
+**DO NOT** report them to the `services.gitea` module maintainers.
+**DO** report them to the `services.forgejo` module maintainers instead.
+:::
+
+## Migration from Gitea {#module-forgejo-migration-gitea}
+
+::: {.note}
+Migrating is, while not strictly necessary at this point, highly recommended.
+Both modules and projects are likely to divide further with each release.
+Which might lead to an even more involved migration.
+:::
+
+### Full-Migration {#module-forgejo-migration-gitea-default}
+
+This will migrate the state directory (data), rename and chown the database and
+delete the gitea user.
+
+::: {.note}
+This will also change the git remote ssh-url user from `gitea@` to `forgejo@`,
+when using the host's openssh server (default) instead of the integrated one.
+:::
+
+Instructions for PostgreSQL (default). Adapt accordingly for other databases:
+
+```sh
+systemctl stop gitea
+mv /var/lib/gitea /var/lib/forgejo
+runuser -u postgres -- psql -c '
+  ALTER USER gitea RENAME TO forgejo;
+  ALTER DATABASE gitea RENAME TO forgejo;
+'
+nixos-rebuild switch
+systemctl stop forgejo
+chown -R forgejo:forgejo /var/lib/forgejo
+systemctl restart forgejo
+```
+
+### Alternatively, keeping the gitea user {#module-forgejo-migration-gitea-impersonate}
+
+Alternatively, instead of renaming the database, copying the state folder and
+changing the user, the forgejo module can be set up to re-use the old storage
+locations and database, instead of having to copy or rename them.
+Make sure to disable `services.gitea`, when doing this.
+
+```nix
+services.gitea.enable = false;
+
+services.forgejo = {
+  enable = true;
+  user = "gitea";
+  group = "gitea";
+  stateDir = "/var/lib/gitea";
+  database.name = "gitea";
+  database.user = "gitea";
+};
+
+users.users.gitea = {
+  home = "/var/lib/gitea";
+  useDefaultShell = true;
+  group = "gitea";
+  isSystemUser = true;
+};
+
+users.groups.gitea = {};
+```
diff --git a/nixos/modules/services/misc/forgejo.nix b/nixos/modules/services/misc/forgejo.nix
index 90b5f16f418..454febda589 100644
--- a/nixos/modules/services/misc/forgejo.nix
+++ b/nixos/modules/services/misc/forgejo.nix
@@ -357,6 +357,14 @@ in
         assertion = cfg.database.createDatabase -> useSqlite || cfg.database.user == cfg.user;
         message = "services.forgejo.database.user must match services.forgejo.user if the database is to be automatically provisioned";
       }
+      { assertion = cfg.database.createDatabase && usePostgresql -> cfg.database.user == cfg.database.name;
+        message = ''
+          When creating a database via NixOS, the db user and db name must be equal!
+          If you already have an existing DB+user and this assertion is new, you can safely set
+          `services.forgejo.createDatabase` to `false` because removal of `ensureUsers`
+          and `ensureDatabases` doesn't have any effect.
+        '';
+      }
     ];
 
     services.forgejo.settings = {
@@ -423,22 +431,11 @@ in
       ensureUsers = [
         {
           name = cfg.database.user;
-          ensurePermissions = { "DATABASE ${cfg.database.name}" = "ALL PRIVILEGES"; };
+          ensureDBOwnership = true;
         }
       ];
     };
 
-    # Work around 'pq: permission denied for schema public' with postgres v15, until a
-    # solution for `services.postgresql.ensureUsers` is found.
-    # See https://github.com/NixOS/nixpkgs/issues/216989
-    systemd.services.postgresql.postStart = lib.mkIf (
-      usePostgresql
-      && cfg.database.createDatabase
-      && lib.strings.versionAtLeast config.services.postgresql.package.version "15.0"
-    ) (lib.mkAfter ''
-      $PSQL -tAc 'ALTER DATABASE "${cfg.database.name}" OWNER TO "${cfg.database.user}";'
-    '');
-
     services.mysql = optionalAttrs (useMysql && cfg.database.createDatabase) {
       enable = mkDefault true;
       package = mkDefault pkgs.mariadb;
@@ -677,5 +674,6 @@ in
     };
   };
 
+  meta.doc = ./forgejo.md;
   meta.maintainers = with lib.maintainers; [ bendlas emilylange ];
 }
diff --git a/nixos/modules/services/misc/gitea.nix b/nixos/modules/services/misc/gitea.nix
index 3f690f85d62..be528a29899 100644
--- a/nixos/modules/services/misc/gitea.nix
+++ b/nixos/modules/services/misc/gitea.nix
@@ -394,6 +394,14 @@ in
       { assertion = cfg.database.createDatabase -> useSqlite || cfg.database.user == cfg.user;
         message = "services.gitea.database.user must match services.gitea.user if the database is to be automatically provisioned";
       }
+      { assertion = cfg.database.createDatabase && usePostgresql -> cfg.database.user == cfg.database.name;
+        message = ''
+          When creating a database via NixOS, the db user and db name must be equal!
+          If you already have an existing DB+user and this assertion is new, you can safely set
+          `services.gitea.createDatabase` to `false` because removal of `ensureUsers`
+          and `ensureDatabases` doesn't have any effect.
+        '';
+      }
     ];
 
     services.gitea.settings = {
@@ -461,7 +469,7 @@ in
       ensureDatabases = [ cfg.database.name ];
       ensureUsers = [
         { name = cfg.database.user;
-          ensurePermissions = { "DATABASE ${cfg.database.name}" = "ALL PRIVILEGES"; };
+          ensureDBOwnership = true;
         }
       ];
     };
diff --git a/nixos/modules/services/misc/redmine.nix b/nixos/modules/services/misc/redmine.nix
index a296fd3816b..20fa71507b6 100644
--- a/nixos/modules/services/misc/redmine.nix
+++ b/nixos/modules/services/misc/redmine.nix
@@ -267,7 +267,7 @@ in
       { assertion = cfg.database.passwordFile != null || cfg.database.socket != null;
         message = "one of services.redmine.database.socket or services.redmine.database.passwordFile must be set";
       }
-      { assertion = cfg.database.createLocally -> cfg.database.user == cfg.user;
+      { assertion = cfg.database.createLocally -> cfg.database.user == cfg.user && cfg.database.user == cfg.database.name;
         message = "services.redmine.database.user must be set to ${cfg.user} if services.redmine.database.createLocally is set true";
       }
       { assertion = cfg.database.createLocally -> cfg.database.socket != null;
@@ -315,7 +315,7 @@ in
       ensureDatabases = [ cfg.database.name ];
       ensureUsers = [
         { name = cfg.database.user;
-          ensurePermissions = { "DATABASE ${cfg.database.name}" = "ALL PRIVILEGES"; };
+          ensureDBOwnership = true;
         }
       ];
     };
diff --git a/nixos/modules/services/misc/sourcehut/service.nix b/nixos/modules/services/misc/sourcehut/service.nix
index 18c2f5effc5..f08d5eb4687 100644
--- a/nixos/modules/services/misc/sourcehut/service.nix
+++ b/nixos/modules/services/misc/sourcehut/service.nix
@@ -249,10 +249,13 @@ in
       ensureDatabases = [ srvCfg.postgresql.database ];
       ensureUsers = map (name: {
           inherit name;
-          ensurePermissions = { "DATABASE \"${srvCfg.postgresql.database}\"" = "ALL PRIVILEGES"; };
+          # We don't use it because we have a special default database name with dots.
+          # TODO(for maintainers of sourcehut): migrate away from custom preStart script.
+          ensureDBOwnership = false;
         }) [srvCfg.user];
     };
 
+
     services.sourcehut.settings = mkMerge [
       {
         "${srv}.sr.ht".origin = mkDefault "https://${srv}.${cfg.settings."sr.ht".global-domain}";
@@ -378,10 +381,11 @@ in
         extraService
       ])) extraServices)
 
-      # Work around 'pq: permission denied for schema public' with postgres v15, until a
-      # solution for `services.postgresql.ensureUsers` is found.
+      # Work around 'pq: permission denied for schema public' with postgres v15.
       # See https://github.com/NixOS/nixpkgs/issues/216989
       # Workaround taken from nixos/forgejo: https://github.com/NixOS/nixpkgs/pull/262741
+      # TODO(to maintainers of sourcehut): please migrate away from this workaround
+      # by migrating away from database name defaults with dots.
       (lib.mkIf (
           cfg.postgresql.enable
           && lib.strings.versionAtLeast config.services.postgresql.package.version "15.0"