eos-migrate-firefox-profile

#!/usr/bin/python3
#
# eos-migrate-firefox-profile: move users' Firefox profile to its new home
#
# Copyright © 2020 Endless OS LLC
# Authors:
#  Will Thompson <wjt@endlessos.org>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
#
#
# Endless's Firefox Flatpak stored its data in the real ~/.mozilla in the user's
# home directory. Mozilla's Firefox Flatpak stores its data in what it thinks is
# ~/.mozilla, but which is actually ~/.var/app/$APP_ID/.mozilla through the magic of
# --persist=.mozilla.
#
# eos-update-flatpak-repos adjusts our Flatpak's permissions to match Mozilla's more
# restrictive set. This script moves the actual user data.
import os
from gi.repository import GLib

APP_DATA_DIR = os.path.expanduser("~/.var/app/org.mozilla.Firefox")
APP_DATA_DIR_DOT_MOZILLA = os.path.join(APP_DATA_DIR, ".mozilla")
HOME_DOT_MOZILLA = os.path.expanduser("~/.mozilla")
PROFILES_INI = os.path.join(HOME_DOT_MOZILLA, "firefox", "profiles.ini")

ENDLESS_FLATPAK_INSTALL_GROUP = "InstallFF6C2EBF42BF07E5"
MOZILLA_FLATPAK_INSTALL_GROUP = "InstallCF146F38BCAB2D21"

MIMEAPPS_LIST = os.path.join(GLib.get_user_config_dir(), "mimeapps.list")
MIMEAPPS_GROUPS = [
    "Default Applications",
    "Added Associations",
    "Removed Associations",
]
OLD_DESKTOP_FILE = "org.mozilla.Firefox.desktop"
NEW_DESKTOP_FILE = "org.mozilla.firefox.desktop"


def update_mimeapps_list(path):
    """Update file associations, which in particular includes x-scheme-handler/http and
    friends to specify the default web browser.

    Strictly speaking, a user may have had the old Firefox specified as their default
    browser without ever having launched it (in which case this script would not be
    run); in practice, this seems vanishingly unlikely.

    We cannot use GLib's own API to query what mime types the old Firefox desktop file
    is a handler for, because we can't construct a GDesktopAppInfo for it, because its
    desktop file no longer exists.
    """

    keyfile = GLib.KeyFile()
    try:
        keyfile.load_from_file(
            path, GLib.KeyFileFlags.KEEP_COMMENTS | GLib.KeyFileFlags.KEEP_TRANSLATIONS,
        )
    except GLib.GError as gerror:
        if gerror.matches(GLib.file_error_quark(), GLib.FileError.NOENT):
            return

        raise

    changed = False

    for group in MIMEAPPS_GROUPS:
        if not keyfile.has_group(group):
            continue

        keys, _length = keyfile.get_keys(group)
        for key in keys:
            values = keyfile.get_string_list(group, key)
            try:
                i = values.index(OLD_DESKTOP_FILE)
            except ValueError:
                pass
            else:
                values[i] = NEW_DESKTOP_FILE
                keyfile.set_string_list(group, key, values)
                changed = True

    if changed:
        keyfile.save_to_file(path)


def copy_install_section(path):
    """The default profile is keyed by a hash of the Firefox executable's installed
    path. Endless's Firefox Flatpak has the executable at a different path to Mozilla's.
    Copy the Endless installation's data to the group for Mozilla's."""
    keyfile = GLib.KeyFile()
    keyfile.load_from_file(
        path, GLib.KeyFileFlags.KEEP_COMMENTS | GLib.KeyFileFlags.KEEP_TRANSLATIONS,
    )

    has_mozilla_group = keyfile.has_group(MOZILLA_FLATPAK_INSTALL_GROUP)
    has_endless_group = keyfile.has_group(ENDLESS_FLATPAK_INSTALL_GROUP)

    if not has_mozilla_group and has_endless_group:
        keys, _length = keyfile.get_keys(ENDLESS_FLATPAK_INSTALL_GROUP)
        for key in keys:
            value = keyfile.get_string(ENDLESS_FLATPAK_INSTALL_GROUP, key)
            keyfile.set_string(MOZILLA_FLATPAK_INSTALL_GROUP, key, value)

        # Uses g_file_set_contents(), is reasonably atomic
        keyfile.save_to_file(path)


def main():
    if (
        os.path.isdir(APP_DATA_DIR)
        and not os.path.isdir(APP_DATA_DIR_DOT_MOZILLA)
        and os.path.isdir(HOME_DOT_MOZILLA)
    ):
        update_mimeapps_list(MIMEAPPS_LIST)
        copy_install_section(PROFILES_INI)
        os.rename(HOME_DOT_MOZILLA, APP_DATA_DIR_DOT_MOZILLA)


if __name__ == "__main__":
    main()