Add typed models for projects

default.nix

@@ -63,6 +63,8 @@ rec {
     };
   };
 
+  project-models = import ./projects/models.nix { inherit lib pkgs sources; };
+
   # TODO: find a better place for this
   metrics = with lib; {
     projects = attrNames raw-projects;

flake.nix

@@ -13,6 +13,8 @@
   inputs.sops-nix.url = "github:Mic92/sops-nix";
   inputs.buildbot-nix.inputs.nixpkgs.follows = "nixpkgs";
   inputs.buildbot-nix.url = "github:nix-community/buildbot-nix";
+  inputs.yants.url = "git+https://code.tvl.fyi/depot.git:/nix/yants.git";
+  inputs.yants.flake = false;
 
   # See <https://github.com/ngi-nix/ngipkgs/issues/24> for plans to support Darwin.
   inputs.systems.url = "github:nix-systems/default-linux";

projects/default.nix

@@ -31,8 +31,10 @@ let
       allowedFiles = [
         "README.md"
         "default.nix"
+        "models.nix"
       ];
     in
+    # TODO: use fileset and filter for `gitTracked` files
     concatMapAttrs names (readDir baseDirectory);
 in
 mapAttrs (name: directory: import directory { inherit lib pkgs sources; }) projectDirectories

projects/models.nix

@@ -0,0 +1,128 @@
+{
+  lib,
+  pkgs,
+  sources,
+}:
+let
+  yants = import sources.yants { };
+
+  inherit (yants)
+    string
+    list
+    option
+    attrs
+    enum
+    either
+    struct
+    drv
+    path
+    restrict
+    ;
+
+  programType = struct "program" {
+    name = string;
+    source = drv;
+    documentation = optionalStruct {
+      build = option string;
+      tests = option string;
+    };
+    examples = nonEmtpyAttrs (option exampleType);
+  };
+
+  serviceType = struct "service" {
+    name = string;
+    documentation = optionalStruct {
+      config = option string;
+    };
+    examples = nonEmtpyAttrs (option exampleType);
+  };
+
+  exampleType = struct "example" {
+    description = option string; # TODO: should this be non-optional?
+    path = either string path;
+    documentation = option string;
+    tests = nonEmtpyAttrs drv;
+  };
+
+  optionalStruct = attrs: option (struct attrs);
+  nonEmtpyAttrs = t: restrict "non-empty-attrs" (a: a != { }) (attrs t);
+in
+rec {
+  project = struct {
+    name = string;
+    metadata = optionalStruct {
+      summary = option string;
+      subgrants = list string;
+    };
+    nixos = struct "nixos" {
+      examples = option (attrs exampleType);
+      tests = option (attrs (option drv));
+      modules = struct "modules" {
+        programs = option (attrs (option programType));
+        services = option (attrs (option serviceType));
+      };
+    };
+  };
+
+  example = project {
+    name = "foobar";
+    nixos = rec {
+      examples = {
+        foobar-cli = {
+          description = ''
+            This is how you can run `foobar` in the terminal.
+          '';
+          path = "";
+          documentation = "https://foo.bar/docs";
+          tests = {
+            # Each example must have at least one test.
+            # If the line below is commented out, an error will be raised.
+            inherit (tests) foobar-cli;
+          };
+        };
+      };
+      tests = {
+        # Set to `null`: needed, but not available
+        basic = null;
+
+        # Needs to be a derivation. Error raised otherwise.
+        #simple = "This will fail.";
+
+        foobar-cli = derivation {
+          name = "myname";
+          builder = "mybuilder";
+          system = "mysystem";
+        };
+      };
+      modules = {
+        # Attributes not defined in the data structure are not allowed.
+        # Uncommenting the line below will raise an error.
+        #hello = { };
+
+        programs = {
+          # Set to `null`: needed, but not available
+          foobar = null;
+
+          foobar-cli = {
+            name = "foobar-cli";
+            source = derivation {
+              name = "foobar-cli-src";
+              builder = "mybuilder";
+              system = "mysystem";
+            };
+            # Each program must have at least one example.
+            # Examples can be null to indicate that they're needed.
+            examples = {
+              inherit (examples) foobar-cli;
+
+              # needed, not available
+              foobar-tui = null;
+            };
+          };
+
+          # Not set: not needed
+        };
+      };
+    };
+  };
+}