flake.nix

@@ -38,33 +38,20 @@
           system = "x86_64-linux";
           config.allowUnfree = true;
         };
-        evalConfig = config: (nixpkgs.lib.nixosSystem {
-          system = "x86_64-linux";
-          modules = [
-            config
-            {
-              nixpkgs.pkgs = pkgs.lib.mkForce pkgs;
-              imports = [ modules.nopersist profiles.container ];
-            }
-          ];
-          specialArgs = {
-            # some of our modules import each other, and evalConfig is used for containers
-            inherit modules evalConfig;
-            sources = inputs;
-          };
-        }).config.system.build.toplevel;
     in {
       nixosConfigurations.parsons = nixpkgs.lib.nixosSystem {
         system = "x86_64-linux";
         modules = [
           ./parsons/configuration.nix
           ./modules/buildinfo.nix
+          ./modules/containers.nix
           sops-nix.nixosModules.sops
           { nixpkgs.pkgs = pkgs; }
         ];
         specialArgs = {
           sources = inputs;
-          inherit modules evalConfig;
+          inherit modules profiles;
+          inherit (nixpkgs.lib) nixosSystem;
         };
       };
 

modules/container-profile.nix

@@ -14,12 +14,5 @@
     '';
   };
 
-  # I /suspect/ this is not actually needed.
-  # TODO: find spoons to deal with potential breakage, test removing this
-  networking.defaultGateway = {
-    address = "192.168.100.1";
-    interface = "eth0";
-  };
-
   system.stateVersion = lib.mkDefault "21.05";
 }

modules/containers.nix

@@ -0,0 +1,95 @@
+{ config, lib, pkgs, modules, profiles, sources, nixosSystem, ... }:
+
+let
+  mkIPv4 = index: local:
+    "192.168.${if local then "100" else "101"}.${toString index}";
+  mkIPv6 = index: local:
+    "fd00::${if local then "100" else "101"}:${toString index}";
+
+  evalConfig = nixosConfig: (nixosSystem {
+    inherit (config.nixpkgs) system;
+    modules = [
+      nixosConfig
+      modules.nopersist
+      profiles.container
+      { nixpkgs.pkgs = lib.mkForce pkgs; }
+    ];
+    specialArgs = {
+      inherit modules sources;
+    };
+  }).config.system.build.toplevel;
+
+in {
+  options.hacc.containers = with lib.options;
+    mkOption {
+      description = ''
+        hacc-specific containers. These are a thin wrapper around "normal" nixos containers:
+          - they automatically get an IPv4/IPv6 address assigned
+            (note that these are not guaranteed to be stable across config changes,
+            so please use {option}`containers.<name>.hostAddress` & friends to
+            reference them elsewhere)
+          - they set a couple default options (e.g. ephemeral, autoStart, privateNetwork)
+          - they are evaluated with our own version of {nix}`evalConfig`, which includes a
+            couple more modules by default, use our version of `nixpkgs`, and includes the
+            {nix}`profiles.containers` profile setting sane defaults for containers.
+      '';
+      default = { };
+      type = with lib.types;
+        types.attrsOf (types.submodule {
+          options = {
+            bindToPersist = mkOption {
+              default = true;
+              type = types.bool;
+              description =
+                "Wether to mount /persist/containers/<name> at /persist into this container.";
+            };
+
+            bindSecrets = mkOption {
+              default = false;
+              type = types.bool;
+              description =
+                "Whether to mount /run/secrets/<name> at /secrets into this container.";
+            };
+
+            config = mkOption {
+              type = types.unspecified;
+              description =
+                "The container's config, to be evaluated with our own {nix}`evalConfig`.";
+            };
+          };
+        });
+    };
+
+  # wrapped into imap1, which enumerates the containers; IP addresses are then
+  # simply assigned based on the order the containers are in the list.
+  config.containers = lib.mkMerge (lib.imap1
+    (index: { name, value }: let container = value; in {
+      ${name} = {
+        hostAddress = mkIPv4 index false;
+        localAddress = mkIPv4 index true;
+        hostAddress6 = mkIPv6 index false;
+        localAddress6 = mkIPv6 index true;
+
+        privateNetwork = true;
+        autoStart = true;
+        ephemeral = true;
+
+        bindMounts = lib.mkMerge [
+          (lib.mkIf container.bindToPersist {
+            "/persist" = {
+              hostPath = "/persist/containers/${name}";
+              isReadOnly = false;
+            };
+          })
+          (lib.mkIf container.bindSecrets {
+            "/secrets" = {
+              hostPath = "/run/secrets/${name}";
+              isReadOnly = true;
+            };
+          })
+        ];
+
+        path = evalConfig container.config;
+      };
+    }) (lib.attrsToList config.hacc.containers));
+}

parsons/forgejo.nix

@@ -1,19 +1,8 @@
-{ config, lib, pkgs, evalConfig, ... }:
+{ config, lib, pkgs, ... }:
 
 {
-  containers.forgejo = {
-    privateNetwork = true;
-    hostAddress = "192.168.100.1";
-    localAddress = "192.168.100.10";
-    autoStart = true;
-    ephemeral = true;
-    bindMounts = {
-      "/persist" = {
-        hostPath = "/persist/containers/forgejo";
-        isReadOnly = false;
-      };
-    };
-    path = evalConfig ({ config, lib, pkgs, ... }: {
+  hacc.containers.forgejo = {
+    config = { lib, pkgs, ... }: {
       system.stateVersion = "21.11";
 
       environment.systemPackages = [ pkgs.forgejo ];
@@ -79,7 +68,7 @@
       services.openssh = {
         enable = true;
         listenAddresses = [ {
-          addr = "192.168.100.10";
+          addr = config.containers.forgejo.localAddress;
           port = 22;
         } ];
         settings = {
@@ -87,7 +76,7 @@
           AcceptEnv = "GIT_PROTOCOL";
         };
       };
-    });
+    };
   };
 
   services.nginx.virtualHosts."git.infra4future.de" = {

parsons/hedgedoc-hacc.nix

@@ -1,4 +1,4 @@
-{ config, lib, pkgs, evalConfig, ... }:
+{ config, lib, pkgs, ... }:
 
 {
 
@@ -6,20 +6,11 @@
     "hedgedoc-hacc/env" = {};
   };
 
-  containers.pad-hacc = {
-    privateNetwork = true;
-    hostAddress = "192.168.100.1";
-    localAddress = "192.168.100.5";
-    autoStart = true;
-    ephemeral = true;
-    bindMounts = {
-      "/persist" = {
-        hostPath = "/persist/containers/pad-hacc";
-        isReadOnly = false;
-      };
-      "/secrets".hostPath = "/run/secrets/hedgedoc-hacc";
-    };
-    path = evalConfig ({ config, lib, ... }: {
+  containers.pad-hacc.bindMounts = {
+    "/secrets".hostPath = "/run/secrets/hedgedoc-hacc";
+  };
+  hacc.containers.pad-hacc = {
+    config = { config, lib, ... }: {
       services.hedgedoc = {
         enable = true;
         settings = {
@@ -78,7 +69,7 @@
         location = "/persist/backups/postgres";
       };
       hacc.bindToPersist = [ "/var/lib/hedgedoc" ];
-    });
+    };
   };
   services.nginx.virtualHosts."pad.hacc.earth" = {
     enableACME = true;

parsons/hedgedoc-i4f.nix

@@ -1,19 +1,8 @@
-{ config, lib, pkgs, evalConfig, ... }:
+{ config, lib, pkgs, ... }:
 
 {
-  containers.pad-i4f = {
-    privateNetwork = true;
-    hostAddress = "192.168.100.1";
-    localAddress = "192.168.100.6";
-    autoStart = true;
-    ephemeral = true;
-    bindMounts = {
-      "/persist" = {
-        hostPath = "/persist/containers/pad-i4f";
-        isReadOnly = false;
-      };
-    };
-    path = evalConfig ({ config, lib, ... }: {
+  hacc.containers.pad-i4f = {
+    config = { config, lib, ... }: {
       services.hedgedoc = {
         enable = true;
         settings = {
@@ -57,7 +46,7 @@
         location = "/persist/backups/postgres";
       };
       hacc.bindToPersist = [ "/var/lib/hedgedoc" ];
-    });
+    };
   };
 
   services.nginx.virtualHosts."pad.infra4future.de" = {

parsons/mattermost.nix

@@ -1,26 +1,14 @@
-{ config, pkgs, lib, evalConfig, ...}:
+{ config, pkgs, lib, ...}:
 
 {
   sops.secrets = {
     "mattermost/env" = {};
   };
 
-  containers.mattermost = {
-    autoStart = true;
-    privateNetwork = true;
-    hostAddress = "192.168.100.1";
-    localAddress = "192.168.100.3";
-    ephemeral = true;
+  hacc.containers.mattermost = {
+    bindSecrets = true;
 
-    bindMounts = {
-      "/persist" = {
-        hostPath = "/persist/containers/mattermost";
-        isReadOnly = false;
-      };
-      "/secrets".hostPath = "/run/secrets/mattermost";
-    };
-
-    path = evalConfig ({ config, lib, pkgs, ... }: {
+    config = { config, lib, pkgs, ... }: {
       systemd.services.mattermost.serviceConfig.EnvironmentFile =
         lib.mkForce "/secrets/env";
 
@@ -218,7 +206,7 @@
         startAt = "*-*-* 23:45:00";
         location = "/persist/backups/postgres";
       };
-    });
+    };
   };
 
   services.nginx.virtualHosts."mattermost.infra4future.de" = {

parsons/nextcloud.nix

@@ -1,19 +1,8 @@
-{ config, lib, pkgs, evalConfig, ... }:
+{ config, lib, pkgs, ... }:
 
 {
-  containers.nextcloud = {
-    autoStart = true;
-    privateNetwork = true;
-    hostAddress = "192.168.100.1";
-    localAddress = "192.168.100.2";
-    ephemeral = true;
-    bindMounts = {
-      "/persist" = {
-        hostPath = "/persist/containers/nextcloud";
-        isReadOnly = false;
-      };
-    };
-    path = evalConfig ({ config, lib, pkgs, ... }: {
+  hacc.containers.nextcloud = {
+    config = { config, lib, pkgs, ... }: {
       environment.systemPackages = [ pkgs.htop ];
 
       services.nextcloud = {
@@ -82,7 +71,7 @@
         requires = ["postgresql.service"];
         after = ["postgresql.service"];
       };
-    });
+    };
   };
 
   services.nginx.virtualHosts."cloud.infra4future.de" = {

parsons/tracktrain.nix

@@ -1,4 +1,4 @@
-{ config, lib, pkgs, evalConfig, ... }:
+{ config, lib, pkgs, ... }:
 
 let
   tracktrain-config = ''
@@ -25,14 +25,14 @@ in
     enableACME = true;
     forceSSL = true;
     locations."/" = {
-      proxyPass = "http://192.168.42.41:4000";
+      proxyPass = "http://${config.containers.tracktrain.localAddress}:4000";
       proxyWebsockets = true;
     };
     # note: this shadows the /metrics endpoint of tracktrain
     # in case you remove this, please consider putting something
     # else here to keep it from being publicly scrapable
     locations."/metrics/" = {
-      proxyPass = "http://192.168.42.41:2342";
+      proxyPass = "http://${config.containers.tracktrain.localAddress}:2342";
       proxyWebsockets = true;
       extraConfig = ''
         rewrite  ^/metrics/(.*)  /$1 break;
@@ -40,21 +40,10 @@ in
     };
   };
 
-  containers.tracktrain = {
-    privateNetwork = true;
-    hostAddress = "192.168.42.40";
-    localAddress = "192.168.42.41";
-    autoStart = true;
-    ephemeral = true;
-    bindMounts = {
-      "/persist" = {
-        hostPath = "/persist/containers/tracktrain";
-        isReadOnly = false;
-      };
-      "/secrets".hostPath = "/run/secrets/tracktrain";
-    };
+  hacc.containers.tracktrain = {
+    bindSecrets = true;
 
-    path = evalConfig ({ config, lib, pkgs, ... }: {
+    config = { config, lib, pkgs, ... }: {
       system.stateVersion = "21.11";
 
       users.users.tracktrain = {
@@ -151,7 +140,7 @@ in
       systemd.services.grafana.serviceConfig.EnvironmentFile =
         "/secrets/env";
       hacc.bindToPersist = [ "/var/lib/grafana" ];
-    });
+    };
   };
 
 }

parsons/uffd.nix

@@ -1,19 +1,8 @@
-{ config, lib, pkgs, evalConfig, ... }:
+{ config, lib, pkgs, ... }:
 
 {
-  containers.uffd = {
-    privateNetwork = true;
-    hostAddress = "192.168.100.1";
-    localAddress = "192.168.100.9";
-    autoStart = true;
-    ephemeral = true;
-    bindMounts = {
-      "/persist" = {
-        hostPath = "/persist/containers/uffd";
-        isReadOnly = false;
-      };
-    };
-    path = evalConfig ({ config, lib, pkgs, ... }: {
+  hacc.containers.uffd = {
+    config = { config, lib, pkgs, ... }: {
       services.uwsgi = {
         enable = true;
         plugins = [ "python3" ];
@@ -29,7 +18,7 @@
           hook-pre-app = "exec:FLASK_APP=${pkgs.uffd}/lib/python3.10/site-packages/uffd flask db upgrade";
         };
       };
-    });
+    };
   };
   services.nginx.virtualHosts."login.infra4future.de" = {
     enableACME = true;