erpnext-nix/test-vm/configuration.nix

{ pkgs, lib, config, modulesPath, ... }:
with lib;
{
  imports = [
    "${modulesPath}/profiles/minimal.nix"
    "${modulesPath}/profiles/qemu-guest.nix"
    "${modulesPath}/virtualisation/qemu-vm.nix"
  ];

  config = {
    services.qemuGuest.enable = true;

    fileSystems."/" = {
      device = "/dev/disk/by-label/nixos";
      fsType = "ext4";
      autoResize = true;
    };

    boot = {
      growPartition = true;
      loader.timeout = 5;
    };

    virtualisation = {
      diskSize = 8000; # MB
      memorySize = 2048; # MB

      # We don't want to use tmpfs, otherwise the nix store's size will be bounded
      # by a fraction of available RAM.
      writableStoreUseTmpfs = false;
    };

    # So that we can ssh into the VM, see e.g.
    # http://blog.patapon.info/nixos-local-vm/#accessing-the-vm-with-ssh
    services.openssh.enable = true;
    services.openssh.settings.PermitRootLogin = "yes";
    # Give root an empty password to ssh in.
    users.extraUsers.root.password = "";
    users.mutableUsers = false;

    environment.systemPackages = with pkgs; [
      git
      htop
      neovim
    ];

    services.mysql = {
      enable = true;
      package = pkgs.mariadb;
    };

    services.redis.servers = {
      # Queue, naming it "" makes it use default values.
      "".enable = true;

      socketio = {
        enable = true;
        port = 12311;
      };
    };

    users.users.erpnext = {
      description = "User to run erpnext";
      group = "erpnext";
      isSystemUser = true;
    };

    systemd.services.erpnext =
      let
        penv = python3.buildEnv.override {
          extraLibs = [
            python3.pkgs.frappe
            python3.pkgs.erpnext
            python3.pkgs.bench
          ];
        };
      in
        {
          enable = true;
          wantedBy = [ "multi-user.target" ];
          after = [ "mysql.service" "redis.service" "redis-socketio.service" ];
          description = "ERPNext";
          confinement = {
            enable = true;
            packages = [ ];
          };
          script = ''
            export PYTHON_PATH=${penv}/${python3.sitePackages}

            cat > /frappe-bench/sites/apps.txt <<EOF
            frappe
            erpnext
            EOF

            cat >/frape-bench/sites/common_site_config.json <<EOF
            {
              "db_host": "localhost",
              "db_port": 3306,
              "db_name": "erpnext" ,
              "db_password": "erpnext" ,
              "redis_cache": "redis://localhost:6379?db=0",
              "redis_queue": "redis://localhost:6379?db=1",
              "redis_socketio": "redis://localhost:6379?db=2",
              "socketio_port": 3000
            }
            EOF

            # Upstream initializes the DB with this command
            # TODO: Make this idempotent
            cd /frappe-bench/sites
            bench new-site localhost --mariadb-root-password password --admin-password admin
            bench --site localhost install-app erpnext

            echo "Workdir: $tmp"
            # TODO: Run these as systemd units
            node $tmp/apps/frappe/socketio.js &
            gunicorn --chdir="$tmp/sites" --bind=0.0.0.0:9090 --threads=4 --workers=2 --worker-class=gthread --worker-tmp-dir=/dev/shm --timeout=120 --preload frappe.app:application
          '';
          serviceConfig = {
            User = "erpnext";
            NoNewPrivileges = true;
            Type = "simple";
            BindReadOnlyPaths = [
              "${frappe-app}/share/apps/frappe:/frappe-bench/apps/frappe"
              "${erpnext-app}/share/apps/erpnext:/frappe-bench/apps/erpnext"
              "${frappe-erpnext-assets}/share/sites/assets:/frappe-bench/sites/assets"
              # "${penv}:/frappe-bench/env"
            ];
          };
        };
  };
}