nixos/jupyterhub: init service

nixos/modules/module-list.nix

@@ -331,6 +331,7 @@
   ./services/development/bloop.nix
   ./services/development/hoogle.nix
   ./services/development/jupyter/default.nix
+  ./services/development/jupyterhub/default.nix
   ./services/development/lorri.nix
   ./services/editors/emacs.nix
   ./services/editors/infinoted.nix

nixos/modules/services/development/jupyterhub/default.nix

@@ -0,0 +1,190 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+let
+
+  cfg = config.services.jupyterhub;
+
+  kernels = (pkgs.jupyter-kernel.create  {
+    definitions = if cfg.kernels != null
+      then cfg.kernels
+      else  pkgs.jupyter-kernel.default;
+  });
+
+  jupyterhubConfig = pkgs.writeText "jupyterhub_config.py" ''
+    c.JupyterHub.bind_url = "http://${cfg.host}:${toString cfg.port}"
+
+    c.JupyterHub.authentication_class = "${cfg.authentication}"
+    c.JupyterHub.spawner_class = "${cfg.spawner}"
+
+    c.SystemdSpawner.default_url = '/lab'
+    c.SystemdSpawner.cmd = "${cfg.jupyterlabEnv}/bin/jupyterhub-singleuser"
+    c.SystemdSpawner.environment = {
+      'JUPYTER_PATH': '${kernels}'
+    }
+
+    ${cfg.extraConfig}
+  '';
+in {
+  meta.maintainers = with maintainers; [ costrouc ];
+
+  options.services.jupyterhub = {
+    enable = mkEnableOption "Jupyterhub development server";
+
+    authentication = mkOption {
+      type = types.str;
+      default = "jupyterhub.auth.PAMAuthenticator";
+      description = ''
+        Jupyterhub authentication to use
+
+        There are many authenticators available including: oauth, pam,
+        ldap, kerberos, etc.
+      '';
+    };
+
+    spawner = mkOption {
+      type = types.str;
+      default = "systemdspawner.SystemdSpawner";
+      description = ''
+        Jupyterhub spawner to use
+
+        There are many spawners available including: local process,
+        systemd, docker, kubernetes, yarn, batch, etc.
+      '';
+    };
+
+    extraConfig = mkOption {
+      type = types.lines;
+      default = "";
+      description = ''
+        Extra contents appended to the jupyterhub configuration
+
+        Jupyterhub configuration is a normal python file using
+        Traitlets. https://jupyterhub.readthedocs.io/en/stable/getting-started/config-basics.html. The
+        base configuration of this module was designed to have sane
+        defaults for configuration but you can override anything since
+        this is a python file.
+      '';
+      example = literalExample ''
+         c.SystemdSpawner.memory = "8G"
+         c.SystemdSpawner.cpus = "2"
+      '';
+    };
+
+    jupyterhubEnv = mkOption {
+      type = types.package;
+      default = (pkgs.python3.withPackages (p: with p; [
+        jupyterhub
+        jupyterhub-systemdspawner
+      ]));
+      description = ''
+        Python environment to run jupyterhub
+
+        Customizing will affect the packages available in the hub and
+        proxy. This will allow packages to be available for the
+        extraConfig that you may need. This will not normally need to
+        be changed.
+      '';
+    };
+
+    jupyterlabEnv = mkOption {
+      type = types.package;
+      default = (pkgs.python3.withPackages (p: with p; [
+        jupyterhub
+        jupyterlab
+      ]));
+      description = ''
+        Python environment to run jupyterlab
+
+        Customizing will affect the packages available in the
+        jupyterlab server and the default kernel provided. This is the
+        way to customize the jupyterlab extensions and jupyter
+        notebook extensions. This will not normally need to
+        be changed.
+      '';
+    };
+
+    kernels = mkOption {
+      type = types.nullOr (types.attrsOf(types.submodule (import ../jupyter/kernel-options.nix {
+        inherit lib;
+      })));
+
+      default = null;
+      example = literalExample ''
+        {
+          python3 = let
+            env = (pkgs.python3.withPackages (pythonPackages: with pythonPackages; [
+                    ipykernel
+                    pandas
+                    scikitlearn
+                  ]));
+          in {
+            displayName = "Python 3 for machine learning";
+            argv = [
+              "''${env.interpreter}"
+              "-m"
+              "ipykernel_launcher"
+              "-f"
+              "{connection_file}"
+            ];
+            language = "python";
+            logo32 = "''${env}/''${env.sitePackages}/ipykernel/resources/logo-32x32.png";
+            logo64 = "''${env}/''${env.sitePackages}/ipykernel/resources/logo-64x64.png";
+          };
+        }
+      '';
+      description = ''
+        Declarative kernel config
+
+        Kernels can be declared in any language that supports and has
+        the required dependencies to communicate with a jupyter server.
+        In python's case, it means that ipykernel package must always be
+        included in the list of packages of the targeted environment.
+      '';
+    };
+
+    port = mkOption {
+      type = types.port;
+      default = 8000;
+      description = ''
+        Port number Jupyterhub will be listening on
+      '';
+    };
+
+    host = mkOption {
+      type = types.str;
+      default = "0.0.0.0";
+      description = ''
+        Bind IP JupyterHub will be listening on
+      '';
+    };
+
+    stateDirectory = mkOption {
+      type = types.str;
+      default = "jupyterhub";
+      description = ''
+        Directory for jupyterhub state (token + database)
+      '';
+    };
+  };
+
+  config = mkMerge [
+    (mkIf cfg.enable  {
+      systemd.services.jupyterhub = {
+        description = "Jupyterhub development server";
+
+        after = [ "network.target" ];
+        wantedBy = [ "multi-user.target" ];
+
+        serviceConfig = {
+          Restart = "always";
+          ExecStart = "${cfg.jupyterhubEnv}/bin/jupyterhub --config ${jupyterhubConfig}";
+          User = "root";
+          StateDirectory = cfg.stateDirectory;
+          WorkingDirectory = "/var/lib/${cfg.stateDirectory}";
+        };
+      };
+    })
+  ];
+}