charm.py

#!/usr/bin/env python3
# Copyright 2020 David Garcia
# See LICENSE file for licensing details.

from apt.progress.base import InstallProgress
import logging
import os
import shutil
import time

from jinja2 import Template
from ops.charm import CharmBase
from ops.framework import StoredState
from ops.main import main
from ops.model import (
    MaintenanceStatus,
    ActiveStatus,
    # BlockedStatus,
)
from utils import (
    service_stop,
    service_restart,
    install_apt,
    remove_apt,
    shell,
    upgrade_apt,
)


# from typing import Dict, Any
logger = logging.getLogger(__name__)

APT_PROXY_PATH = "/etc/apt/apt.conf.d/99-HIVE-apt-proxy"
APT_PROXY_TEMPLATE = "./templates/proxy"
APT_REQUIREMENTS = [
    "firefox",
    "indicator-applet-session",
    "libnotify-bin",
    "mate-desktop",
    "mate-applets",
    "mate-applet-brisk-menu",
    "mate-control-center",
    "mate-indicator-applet",
    "mate-notification-daemon",
    "mate-session-manager",
    "mate-terminal",
    "xrdp",
]

POLKIT_PATH = "/etc/polkit-1/localauthority/50-local.d/color.pkla"
POLKIT_TEMPLATE = "./templates/color.pkla"
PUBLIC_IP_PATH = "/etc/netplan/60-no-public-ip.yaml"
PUBLIC_IP_TEMPLATE = "./templates/60-no-public-ip.yaml"
SNAP_INSTALLS = [
    #"code --classic",
]
STARTWM_PATH = "/etc/xrdp/startwm.sh"
STARTWM_TEMPLATE = "./templates/startwm.sh"
# WM_COMMAND = "startxfce4" # xubuntu-desktop
# WM_COMMAND = "budgie-desktop" # budgie-desktop-environment
WM_COMMAND = "mate-session"  # mate-desktop


class VirtualPCCharm(CharmBase, InstallProgress):
    _stored = StoredState()

    def __init__(self, *args):
        super().__init__(*args)
        InstallProgress.__init__(self)

        self._stored.set_default()
        self.last_status_update = time.time()
        self._stored.set_default(ldap_installed=False)

        # Basic hooks
        self.framework.observe(self.on.install, self._on_install)
        self.framework.observe(self.on.start, self._on_start)
        self.framework.observe(self.on.stop, self._on_stop)
        self.framework.observe(self.on.config_changed, self._on_config_changed)
        self.framework.observe(self.on.update_status, self._on_update_status)

        # Actions hooks
        self.framework.observe(self.on["add-package"].action, self._add_package)
        self.framework.observe(self.on["add-snap"].action, self._add_snap)
        self.framework.observe(self.on["announce"].action, self._announce)
        self.framework.observe(self.on["reboot"].action, self._reboot)
        self.framework.observe(self.on["remove-package"].action, self._remove_package)
        self.framework.observe(self.on["remove-snap"].action, self._remove_snap)
        self.framework.observe(self.on["update-system"].action, self._update_system)
        self.framework.observe(self.on["integrate-ldap"].action, self._ldap_integration)

        # Relations hooks

    # Override InstallProgress to update our status
    def status_change(self, pkg, percent, status):
        if (time.time() - self.last_status_update) < 2:
            return
        self.last_status_update = time.time()
        message = str(int(percent)) + "% " + status
        self.unit.status = MaintenanceStatus(message)

    # Basic hooks
    def _on_install(self, _):

        self.unit.status = MaintenanceStatus("Setting up apt proxy")
        with open(APT_PROXY_TEMPLATE, "r") as template:
            content = Template(template.read()).render()
            with open(APT_PROXY_PATH, "w") as proxy:
                proxy.write(content)

        self.unit.status = MaintenanceStatus("Installing apt packages")
        install_apt(packages=APT_REQUIREMENTS, update=True, progress=self)
        service_stop('xrdp')

        self.unit.status = MaintenanceStatus("Installing snaps")
        for snap in SNAP_INSTALLS:
            shell("snap install " + snap)

        self.unit.status = MaintenanceStatus("Setting default display manager")
        shell("echo /usr/sbin/lightdm | sudo tee /etc/X11/default-display-manager")

        self.unit.status = MaintenanceStatus("Adding XRDP to ssl-cert group")
        shell("adduser xrdp ssl-cert")

        self.unit.status = MaintenanceStatus("Generating Window Manager startup script")
        with open(STARTWM_TEMPLATE, "r") as template:
            content = Template(template.read()).render(command=WM_COMMAND)
            with open(STARTWM_PATH, "w") as startwm:
                startwm.write(content)

        self.unit.status = MaintenanceStatus("Generating Polkit files")
        with open(POLKIT_TEMPLATE, "r") as template:
            content = Template(template.read()).render()
            with open(POLKIT_PATH, "w") as polkit:
                polkit.write(content)

        self.unit.status = MaintenanceStatus("Removing public IP interface")
        with open(PUBLIC_IP_TEMPLATE, "r") as template:
            content = Template(template.read()).render()
            with open(PUBLIC_IP_PATH, "w") as public_ip:
                public_ip.write(content)
        shell("netplan apply")

        self._stored.installed = True
        self.unit.status = self._get_current_status()

    def _on_start(self, _):
        self.unit.status = MaintenanceStatus("Starting XRDP server")
        service_restart('xrdp')
        self._stored.started = True
        self.unit.status = self._get_current_status()

    def _on_stop(self, _):
        service_stop('xrdp')
        self._stored.started = False
        self.unit.status = self._get_current_status()

    def _on_config_changed(self, _):
        self.unit.status = self._get_current_status()

    def _on_update_status(self, _):
        self.unit.status = self._get_current_status()

    # Action hooks
    def _add_package(self, event):
        self.unit.status = MaintenanceStatus("Installing apt packages")
        install_apt(packages=event.params["package"].split(','),
                    update=True, progress=self)
        self.unit.status = self._get_current_status()

    def _add_snap(self, event):
        self.unit.status = MaintenanceStatus("Installing snaps")
        for snap in event.params["package"].split(','):
            shell("snap install " + snap)
        self.unit.status = self._get_current_status()

    def _announce(self, event):
        self.unit.status = MaintenanceStatus("Announce")
        message = event.params["message"]
        shell("su - ubuntu -c 'XDG_RUNTIME_DIR=/run/user/$(id -u) notify-send \"" + message + "\"'")
        self.unit.status = self._get_current_status()

    def _reboot(self, _):
        self.unit.status = MaintenanceStatus("Rebooting server")
        shell("su - ubuntu -c 'XDG_RUNTIME_DIR=/run/user/$(id -u) notify-send \"System is going down for reboot in 60 seconds\" -u critical'")
        shell("shutdown -r +1")
        self.unit.status = self._get_current_status()

    def _remove_package(self, event):
        self.unit.status = MaintenanceStatus("Removing apt packages")
        remove_apt(packages=event.params["package"].split(','),
                   update=True, progress=self)
        self.unit.status = self._get_current_status()

    def _remove_snap(self, event):
        self.unit.status = MaintenanceStatus("Removing snaps")
        for snap in event.params["package"].split(','):
            shell("snap remove " + snap)
        self.unit.status = self._get_current_status()

    def _update_system(self, _):
        self.unit.status = MaintenanceStatus("Updating system")
        upgrade_apt(update=True, progress=self)
        self.unit.status = self._get_current_status()

    def _ldap_integration(self, event):
        self.unit.status = MaintenanceStatus("Configuring Ldap autentication")
        self._configure_ldap(event.params["ldap_host"], event.params["ldap_domain"], event.params["ldap_password"])
        if not self._stored.ldap_installed:
            install_apt(packages=["ldap-auth-client", "nscd"],
                        update=True, progress=self)
            # edit /etc/nsswitch.conf
            shell("sudo sed -E -i '/passwd|group|shadow/ !b; s/$/ ldap/' /etc/nsswitch.conf")
            # restart nscd
            shell("sudo systemctl restart nscd")
            #create a home directory when user login
            shell("echo session required pam_mkhomedir.so skel=/etc/skel umask=077 | sudo tee /etc/pam.d/common-session")
            self._stored.ldap_installed = True
        else:
            shell("dpkg-reconfigure -f noninteractive ldap-auth-client")
        self.unit.status = ActiveStatus("Ldap autentication configured")

    # Relation hooks

    # Private functions
    def _get_current_status(self):
        status_type = ActiveStatus
        status_msg = ""
        if self._stored.installed:
            status_msg = "Ready"
        return status_type(status_msg)

    def _configure_ldap(self, host, domain, password):
        #configure ldap-auth-config with debconf
        shell("echo ldap-auth-config ldap-auth-config/rootbindpw password {} | sudo debconf-set-selections".format(password))
        shell("echo ldap-auth-config ldap-auth-config/bindpw password {} | sudo debconf-set-selections".format(password))
        shell("echo ldap-auth-config ldap-auth-config/binddn string cn=admin,dc={},dc={} | sudo debconf-set-selections".format(domain.split(".")[0],domain.split(".")[1]))
        shell("echo ldap-auth-config ldap-auth-config/dblogin boolean false | sudo debconf-set-selections")
        shell("echo ldap-auth-config ldap-auth-config/rootbinddn string cn=admin,dc={},dc={} | sudo debconf-set-selections".format(domain.split(".")[0],domain.split(".")[1]))
        shell("echo ldap-auth-config ldap-auth-config/ldapns/ldap-server string ldap://{} | sudo debconf-set-selections".format(host))
        shell("echo ldap-auth-config ldap-auth-config/override boolean true | sudo debconf-set-selections")
        shell("echo ldap-auth-config ldap-auth-config/ldapns/ldap_version select 3 | sudo debconf-set-selections")
        shell("echo ldap-auth-config ldap-auth-config/dbrootlogin boolean true | sudo debconf-set-selections")
        shell("echo ldap-auth-config ldap-auth-config/ldapns/base-dn string dc={},dc={} | sudo debconf-set-selections".format(domain.split(".")[0],domain.split(".")[1]))
        shell("echo ldap-auth-config ldap-auth-config/move-to-debconf boolean true | sudo debconf-set-selections")
        shell("echo ldap-auth-config ldap-auth-config/pam_password select clear | sudo debconf-set-selections")


if __name__ == "__main__":
    main(VirtualPCCharm)