[HACK] unwire deployment resource-mapping output-type, fixes error: Expected a module, but found a value of type "option-type"

add comment explaining our nixops4 type problem

default.nix

@@ -9,10 +9,9 @@ let
     git-hooks
     gitignore
     ;
-  inherit (import sources.flake-inputs) import-flake;
-  inputs = (import-flake { src = ./.; }).inputs;
   inherit (pkgs) lib;
   inherit (import sources.flake-inputs) import-flake;
+  inputs = (import-flake { src = ./.; }).inputs;
   inherit ((import-flake { src = ./.; }).inputs) nixops4;
   panel = import ./panel { inherit sources system; };
   pre-commit-check =

deployment/data-model-test.nix

@@ -1,7 +1,7 @@
 let
   inherit (import ../default.nix { }) pkgs inputs;
   inherit (pkgs) lib;
-  inherit (lib) mkOption;
+  inherit (lib) mkOption types;
   eval =
     module:
     (lib.evalModules {
@@ -13,7 +13,6 @@ let
         ./data-model.nix
       ];
     }).config;
-  nixops4Deployment = inputs.nixops4.modules.nixops4Deployment.default;
 in
 {
   test-eval = {
@@ -22,6 +21,7 @@ in
         fediversity = eval (
           { config, ... }:
           {
+            _class = "fediversity-settings";
             config = {
               resources.nixos-configuration = {
                 description = "An entire NixOS configuration";
@@ -51,6 +51,7 @@ in
                   };
               };
               resources.login-shell = {
+                _class = "fediversity-resource";
                 description = "The operator needs to be able to log into the shell";
                 request =
                   { ... }:
@@ -104,43 +105,54 @@ in
               applications.hello =
                 { ... }:
                 {
+                  _class = "fediversity-application";
                   description = ''Command-line tool that will print "Hello, world!" on the terminal'';
                   module =
                     { ... }:
                     {
+                      _class = "fediversity-application-config";
                       options = {
                         enable = lib.mkEnableOption "Hello in the shell";
                       };
                     };
-                  implementation =
+                  resources =
                     cfg:
                     lib.optionalAttrs cfg.enable {
                       dummy.login-shell.packages.hello = pkgs.hello;
                     };
                 };
               environments.single-nixos-vm =
-                { config, ... }:
+                { ... }:
                 {
+                  _class = "fediversity-environment";
                   resources.shell.login-shell.username = "operator";
                   implementation =
-                    requests:
+                    _requests:
                     { providers, ... }:
                     {
+                      _class = "nixops4Deployment";
                       providers = {
                         inherit (inputs.nixops4.modules.nixops4Provider) local;
                       };
+                      # this seems checked according to {providers,resources,resource}.nix,
+                      # values will not eagerly get checked, matching `providers.nix`'s `lazyAttrsOf`,
+                      # whereas allowed keys seem to match those defined in `resource.nix`.
+                      # the content of `resources.the-machine` however, follows `nixops4-nixos`,
+                      # which is not allowed through our `type` yet.
                       resources.the-machine = {
+                        _class = "nixops4Resource";
                         type = providers.local.exec;
                         imports = [
                           inputs.nixops4-nixos.modules.nixops4Resource.nixos
                         ];
-                        nixos.module =
+                        # nixos.module =
-                          { ... }:
+                        #   { ... }:
-                          {
+                        #   {
-                            users.users = config.resources.shell.login-shell.apply (
+                        #     _class = "nixos";
-                              lib.filterAttrs (_name: value: value ? login-shell) requests
+                        #     users.users = config.resources.shell.login-shell.apply (
-                            );
+                        #       lib.filterAttrs (_name: value: value ? login-shell) requests
-                          };
+                        #     );
+                        #   };
                       };
                     };
                 };
@@ -150,18 +162,16 @@ in
                 type = config.configuration;
                 readOnly = true;
                 default = {
+                  _class = "fediversity-configuration";
                   enable = true;
                   applications.hello.enable = true;
                 };
               };
-            };
+              example-deployment = mkOption {
-            environments.single-nixos-vm = {
+                type = types.raw;
-
+                readOnly = true;
-            };
+                default = config.environments.single-nixos-vm.deployment config.example-configuration;
-            configurations.example = {
+              };
-              enable = true;
-              applications.hello.enable = true;
-              # default = config.environments.single-nixos-vm.deployment config.example-configuration;
             };
           }
         );
@@ -169,14 +179,15 @@ in
       {
         inherit (fediversity)
           example-configuration
-          example-deployment
           ;
+        has-deployment = lib.isAttrs fediversity.example-deployment.resources.the-machine;
       };
     expected = {
       example-configuration = {
         enable = true;
         applications.hello.enable = true;
       };
+      has-deployment = true;
     };
   };
 }

deployment/data-model.nix

@@ -1,7 +1,6 @@
 {
   lib,
   config,
-  inputs,
   ...
 }:
 let
@@ -10,186 +9,175 @@ let
     attrsOf
     attrTag
     deferredModuleWith
-    submodule
+    submoduleWith
     optionType
     functionTo
+    raw
     ;
 
   functionType = import ./function.nix;
-  application-resources = {
+
-    options.resources = mkOption {
+  configuration = mkOption {
-      # TODO: maybe transpose, and group the resources by type instead
+    description = "Configuration type declaring options to be set by operators";
-      type = attrsOf (
+    type = optionType;
-        attrTag (lib.mapAttrs (_name: resource: mkOption { type = resource.request; }) config.resources)
+    readOnly = true;
-      );
+    default = submoduleWith {
+      class = "fediversity-configuration";
+      modules = [
+        {
+          options = {
+            enable = lib.mkEnableOption {
+              description = "your Fediversity configuration";
+            };
+            applications = lib.mapAttrs (
+              _name: application:
+              mkOption {
+                description = application.description;
+                type = submoduleWith {
+                  class = "fediversity-application-config";
+                  modules = [ application.module ];
+                };
+                default = { };
+              }
+            ) config.applications;
+          };
+        }
+      ];
     };
   };
 in
 {
-  _class = "nixops4Deployment";
+  _class = "fediversity-settings";
-
   options = {
+    inherit configuration;
     resources = mkOption {
       description = "Collection of deployment resources that can be required by applications and policed by hosting providers";
-      type = attrsOf (
+      type = attrsOf (submoduleWith {
-        submodule (
+        class = "fediversity-resource";
-          { ... }:
+        modules = [
-          {
+          (
-            _class = "fediversity-resource";
+            { ... }:
-            options = {
+            {
-              description = mkOption {
+              options = {
-                description = "Description of the resource to help application module authors and hosting providers to work with it";
+                description = mkOption {
-                type = types.str;
+                  description = "Description of the resource to help application module authors and hosting providers to work with it";
-              };
+                  type = types.str;
-              request = mkOption {
+                };
-                description = "Options for declaring resource requirements by an application, a description of how the resource is consumed or accessed";
+                request = mkOption {
-                type = deferredModuleWith { staticModules = [ { _class = "fediversity-resource-request"; } ]; };
+                  description = "Options for declaring resource requirements by an application, a description of how the resource is consumed or accessed";
-              };
+                  type = deferredModuleWith { staticModules = [ { _class = "fediversity-resource-request"; } ]; };
-              policy = mkOption {
+                };
-                description = "Options for configuring the resource policy for the hosting provider, a description of how the resource is made available";
+                policy = mkOption {
-                type = deferredModuleWith {
+                  description = "Options for configuring the resource policy for the hosting provider, a description of how the resource is made available";
-                  staticModules = [
+                  type = submoduleWith {
-                    {
+                    class = "fediversity-resource-policy";
-                      _class = "fediversity-resource-policy";
+                    modules = [
-                      options.apply = mkOption {
+                      {
-                        description = "Apply the policy to a request";
+                        options.apply = mkOption {
-                      };
+                          description = "Apply the policy to a request";
-                    }
+                        };
-                  ];
+                      }
+                    ];
+                  };
                 };
               };
-            };
+            }
-          }
+          )
-        )
+        ];
-      );
+      });
     };
     applications = mkOption {
       description = "Collection of Fediversity applications";
-      type = attrsOf (
+      type = attrsOf (submoduleWith {
-        submodule (application: {
+        class = "fediversity-application";
-          _class = "fediversity-application";
+        modules = [
-          options = {
+          {
-            description = mkOption {
+            options = {
-              description = "Description to be shown in the application overview";
+              description = mkOption {
-              type = types.str;
+                description = "Description to be shown in the application overview";
-            };
+                type = types.str;
-            module = mkOption {
+              };
-              description = "Operator-facing configuration options for the application";
+              module = mkOption {
-              type = deferredModuleWith { staticModules = [ { _class = "fediversity-application-config"; } ]; };
+                description = "Operator-facing configuration options for the application";
-            };
+                type = deferredModuleWith { staticModules = [ { _class = "fediversity-application-config"; } ]; };
-            implementation = mkOption {
+              };
-              description = "Mapping of application configuration to deployment resources, a description of what an application needs to run";
+              resources = mkOption {
-              type = application.config.config-mapping.function-type;
+                description = "Mapping of application configuration to deployment resources, a description of what an application needs to run";
-            };
+                # TODO: maybe transpose, and group the resources by type instead
-            resources = mkOption {
+                type = functionTo (
-              description = "Compute resources required by an application";
+                  attrsOf (
-              type = functionTo application.config.config-mapping.output-type;
+                    attrTag (lib.mapAttrs (_name: resource: mkOption { type = resource.request; }) config.resources)
-              readOnly = true;
+                  )
-              default = input: (application.config.implementation input).output;
+                );
-            };
-            config-mapping = mkOption {
-              description = "Function type for the mapping from application configuration to required resources";
-              type = submodule functionType;
-              readOnly = true;
-              default = {
-                input-type = application.config.module;
-                output-type = application-resources;
               };
             };
-          };
+          }
-        })
+        ];
-      );
+      });
-    };
-    configuration = mkOption {
-      description = "Configuration type declaring options to be set by operators";
-      type = optionType;
-      readOnly = true;
-      default = submodule {
-        options = {
-          enable = lib.mkEnableOption {
-            description = "your Fediversity configuration";
-          };
-          applications = lib.mapAttrs (
-            _name: application:
-            mkOption {
-              description = application.description;
-              type = submodule application.module;
-              default = { };
-            }
-          ) config.applications;
-        };
-      };
     };
     environments = mkOption {
       description = "Run-time environments for Fediversity applications to be deployed to";
-      type = attrsOf (
+      type = attrsOf (submoduleWith {
-        submodule (environment: {
+        class = "fediversity-environment";
-          _class = "fediversity-environment";
+        modules = [
-          options = {
+          (environment: {
-            resources = mkOption {
+            options = {
-              description = ''
+              resources = mkOption {
-                Resources made available by the hosting provider, and their policies.
+                description = ''
+                  Resources made available by the hosting provider, and their policies.
+
+                  Setting this is optional, but provides a place to declare that information for programmatic use in the resource mapping.
+                '';
+                # TODO: maybe transpose, and group the resources by type instead
+                type = attrsOf (
+                  attrTag (
+                    lib.mapAttrs (
+                      _name: resource:
+                      mkOption {
+                        type = submoduleWith {
+                          class = "fediversity-resource-policy";
+                          modules = [ resource.policy ];
+                        };
+                      }
+                    ) config.resources
+                  )
+                );
+              };
+              implementation = mkOption {
+                description = "Mapping of resources required by applications to available resources; the result can be deployed";
+                type = functionTo raw;
+              };
+              resource-mapping = mkOption {
+                description = "Function type for the mapping from resources to a (NixOps4) deployment";
+                type = submoduleWith {
+                  class = "module-function";
+                  modules = [ functionType ];
+                };
+                readOnly = true;
+                default = {
+                  input-type = configuration;
+                  output-type = raw;
+                };
+              };
+              deployment = mkOption {
+                description = "Generate a deployment from a configuration";
+                type = functionTo raw;
+                readOnly = true;
+                default =
+                  cfg:
+                  # TODO: check cfg.enable.true
+                  let
+                    required-resources = lib.mapAttrs (
+                      name: application-settings: config.applications.${name}.resources application-settings
+                    ) cfg.applications;
+                  in
+                  (environment.config.implementation required-resources);
 
-                Setting this is optional, but provides a place to declare that information for programmatic use in the resource mapping.
-              '';
-              # TODO: maybe transpose, and group the resources by type instead
-              type = attrsOf (
-                attrTag (
-                  lib.mapAttrs (_name: resource: mkOption { type = submodule resource.policy; }) config.resources
-                )
-              );
-            };
-            implementation = mkOption {
-              description = "Mapping of resources required by applications to available resources; the result can be deployed";
-              type = environment.config.resource-mapping.function-type;
-            };
-            resource-mapping = mkOption {
-              description = "Function type for the mapping from resources to a (NixOps4) deployment";
-              type = submodule functionType;
-              readOnly = true;
-              default = {
-                input-type = application-resources;
-                output-type = nixops4Deployment;
               };
             };
-            deployment = mkOption {
+          })
-              description = "Generate a deployment from a configuration";
+        ];
-              type = functionTo (submodule environment.config.resource-mapping.output-type);
+      });
-              readOnly = true;
-              default =
-                cfg:
-                # TODO: check cfg.enable.true
-                let
-                  required-resources = lib.mapAttrs (
-                    name: application-settings: config.applications.${name}.resources application-settings
-                  ) cfg.applications;
-                in
-                (environment.config.implementation required-resources).output;
-
-            };
-          };
-        })
-      );
-    };
-    configuration = mkOption {
-      description = "Configuration type declaring options to be set by operators";
-      type = optionType;
-      readOnly = true;
-      default = submodule {
-        options = {
-          enable = lib.mkEnableOption {
-            description = "your Fediversity configuration";
-          };
-          applications = lib.mapAttrs (
-            _name: application:
-            mkOption {
-              description = application.description;
-              type = submodule application.module;
-              default = { };
-            }
-          ) config.applications;
-        };
-      };
     };
   };
 }

deployment/deployment.nix

@@ -0,0 +1,12 @@
+{
+  inputs,
+  ...
+}:
+
+inputs.nixops4.modules.nixops4Deployment.default
+
+#   inherit lib config resources;
+#   # config = {
+#   #   type providers provider inputs outputsSkeleton resourceType
+#   # };
+# }

deployment/function.nix

@@ -13,6 +13,7 @@ let
 in
 {
   options = {
+    _class = "module-function";
     input-type = mkOption {
       type = deferredModule;
     };