infrastructure/machines/nixos/web02/cas-eleves/default.nix

# SPDX-FileCopyrightText: 2024 Tom Hubrecht <tom.hubrecht@dgnum.eu>
#
# SPDX-License-Identifier: EUPL-1.2

{
  config,
  lib,
  pkgs,
  sources,
  ...
}:

let
  inherit (lib) mapAttrsToList;

  host = "cas.eleves.ens.fr";
  port = 9889;

  python3 =
    let
      nix-pkgs = import sources.nix-pkgs {
        inherit pkgs;
        python3 = pkgs.python312;
      };
    in
    pkgs.python312.override {
      packageOverrides = _: _: {
        inherit (nix-pkgs) django-browser-reload django-bulma-forms loadcredential;

        django-cas-server = nix-pkgs.django-cas-server.overridePythonAttrs (_: {
          patches = [ ./01-pytest-cas.patch ];
        });
      };
    };

  pythonEnv = python3.withPackages (ps: [
    ps.django
    ps.ldap3
    ps.gunicorn
    ps.psycopg

    # Local packages
    ps.django-browser-reload
    ps.django-bulma-forms
    ps.django-cas-server
    ps.loadcredential
  ]);

  staticDrv = pkgs.stdenv.mkDerivation {
    name = "cas_eleves-static";

    src = sources.cas-eleves;

    nativeBuildInputs = [ pythonEnv ];

    configurePhase = ''
      export CE_STATIC_ROOT=$out/static
      export CE_DEBUG=true
      export CREDENTIALS_DIRECTORY=$(pwd)/.credentials
    '';

    doBuild = false;

    installPhase = ''
      mkdir -p $out/static
      python3 manage.py collectstatic
    '';
  };
in

{
  systemd.services = {
    django-cas-eleves = {
      description = "ENS CAS server";
      wantedBy = [ "multi-user.target" ];
      after = [
        "network.target"
        "postgresql.service"
      ];

      serviceConfig = {
        DynamicUser = true;
        LoadCredential = mapAttrsToList (name: value: "${name}:${value}") {
          SECRET_KEY = config.age.secrets."cas_eleves-secret_key_file".path;
        };
        StateDirectory = "django-cas-eleves";
        User = "cas_server";
        WorkingDirectory = sources.cas-eleves;
      };

      environment = {
        CE_ALLOWED_HOSTS = builtins.toJSON [
          "cas-eleves.dgnum.eu"
          "cas.eleves.ens.fr"
        ];
        CE_STATIC_ROOT = staticDrv;
      };

      path = [ pythonEnv ];

      script = ''
        python3 manage.py loaddata patterns
        python3 manage.py migrate
        gunicorn app.wsgi --pythonpath ${sources.cas-eleves} -b 127.0.0.1:${builtins.toString port} --workers=2 --threads=4
      '';
    };

    cas-eleves-cleanup = {
      description = "Periodic cleanup of cas_server database";

      startAt = "daily";

      serviceConfig = {
        Type = "oneshot";

        LoadCredential = mapAttrsToList (name: value: "${name}:${value}") {
          SECRET_KEY = config.age.secrets."cas_eleves-secret_key_file".path;
        };
        StateDirectory = "django-cas-eleves";
        User = "cas_server";
        WorkingDirectory = sources.cas-eleves;
      };

      path = [ pythonEnv ];

      script = ''
        python3 manage.py clearsessions
        python3 manage.py cas_clean_sessions
        python3 manage.py cas_clean_tickets
      '';
    };
  };

  dgn-redirections.permanent."cas-eleves.dgnum.eu" = "cas.eleves.ens.fr";

  dgn-web.simpleProxies.cas-eleves = {
    inherit host port;
    vhostConfig.locations = {
      "/static/".root = staticDrv;
      "= /robots.txt".root = "${staticDrv}/static";
    };
  };

  services.postgresql = {
    ensureDatabases = [ "cas_server" ];
    ensureUsers = [
      {
        name = "cas_server";
        ensureDBOwnership = true;
      }
    ];
  };
}