eos-parental-controls-client: Add a ‘set’ command

This allows the app filter to be set, using the new library API for it.

Signed-off-by: Philip Withnall <withnall@endlessm.com>

https://phabricator.endlessm.com/T24025

eos-parental-controls-client/eos-parental-controls-client.py

@@ -72,6 +72,46 @@ def __get_app_filter_or_error(user_id, interactive):
         raise SystemExit(EXIT_PERMISSION_DENIED)
 
 
+def __set_app_filter(user_id, app_filter, interactive):
+    """Set the app filter for `user_id` off the bus.
+
+    If `interactive` is `True`, interactive polkit authorisation dialogues will
+    be allowed. An exception will be raised on failure."""
+    finished = False
+    exception = None
+
+    def __set_cb(obj, result, user_data):
+        nonlocal finished, exception
+        try:
+            EosParentalControls.set_app_filter_finish(result)
+            finished = True
+        except Exception as e:
+            exception = e
+
+    EosParentalControls.set_app_filter_async(
+        connection=None, user_id=user_id, app_filter=app_filter,
+        allow_interactive_authorization=interactive, cancellable=None,
+        callback=__set_cb, user_data=None)
+
+    context = GLib.MainContext.default()
+    while not finished and not exception:
+        context.iteration(True)
+
+    if exception:
+        raise exception
+
+
+def __set_app_filter_or_error(user_id, app_filter, interactive):
+    """Wrapper around __set_app_filter() which prints an error and raises
+    SystemExit, rather than an internal exception."""
+    try:
+        __set_app_filter(user_id, app_filter, interactive)
+    except GLib.Error as e:
+        print('Error setting app filter for user {}: {}'.format(
+            user_id, e.message), file=sys.stderr)
+        raise SystemExit(EXIT_PERMISSION_DENIED)
+
+
 def __lookup_user_id(user):
     """Convert a command-line specified username or ID into a user ID. If
     `user` is empty, use the current user ID.
@@ -95,23 +135,33 @@ def __lookup_user_id_or_error(user):
         raise SystemExit(EXIT_INVALID_OPTION)
 
 
-def __oars_value_to_string(value):
-    """Convert an EosParentalControls.AppFilterOarsValue to a human-readable
-    string."""
-    mapping = {
+oars_value_mapping = {
     EosParentalControls.AppFilterOarsValue.UNKNOWN: "unknown",
     EosParentalControls.AppFilterOarsValue.NONE: "none",
     EosParentalControls.AppFilterOarsValue.MILD: "mild",
     EosParentalControls.AppFilterOarsValue.MODERATE: "moderate",
     EosParentalControls.AppFilterOarsValue.INTENSE: "intense",
-    }
+}
 
+
+def __oars_value_to_string(value):
+    """Convert an EosParentalControls.AppFilterOarsValue to a human-readable
+    string."""
     try:
-        return mapping[value]
+        return oars_value_mapping[value]
     except KeyError:
         return "invalid (OARS value {})".format(value)
 
 
+def __oars_value_from_string(value_str):
+    """Convert a human-readable string to an
+    EosParentalControls.AppFilterOarsValue."""
+    for k, v in oars_value_mapping.items():
+        if v == value_str:
+            return k
+    raise KeyError('Unknown OARS value ‘{}’'.format(value_str))
+
+
 def command_get(user, quiet=False, interactive=True):
     """Get the app filter for the given user."""
     user_id = __lookup_user_id_or_error(user)
@@ -149,6 +199,30 @@ def command_oars_section(user, section, quiet=False, interactive=True):
         section, user_id, __oars_value_to_string(value)))
 
 
+def command_set(user, app_filter_args=None, quiet=False, interactive=True):
+    """Set the app filter for the given user."""
+    user_id = __lookup_user_id_or_error(user)
+    builder = EosParentalControls.AppFilterBuilder.new()
+
+    for arg in app_filter_args:
+        if '=' in arg:
+            [section, value_str] = arg.split('=', 2)
+            try:
+                value = __oars_value_from_string(value_str)
+            except KeyError:
+                print('Unknown OARS value ‘{}’'.format(value_str),
+                      file=sys.stderr)
+                raise SystemExit(EXIT_INVALID_OPTION)
+            builder.set_oars_value(section, value)
+        else:
+            builder.blacklist_path(arg)
+    app_filter = builder.end()
+
+    __set_app_filter_or_error(user_id, app_filter, interactive)
+
+    print('App filter for user {} set'.format(user_id))
+
+
 def main():
     # Parse command line arguments
     parser = argparse.ArgumentParser(
@@ -204,6 +278,18 @@ def main():
                                           'user)')
     parser_oars_section.add_argument('section', help='OARS section to get')
 
+    # ‘set’ command
+    parser_set = subparsers.add_parser('set', parents=[common_parser],
+                                       help='set current parental controls '
+                                            'settings')
+    parser_set.set_defaults(function=command_set)
+    parser_set.add_argument('user', default='', nargs='?',
+                            help='user ID or username to get the app filter '
+                                 'for (default: current user)')
+    parser_set.add_argument('app_filter_args', nargs='*',
+                            help='paths to blacklist and OARS section=value '
+                                 'pairs to store')
+
     # Parse the command line arguments and run the subcommand.
     args = parser.parse_args()
     args_dict = dict((k, v) for k, v in vars(args).items() if k != 'function')