@@ -35,9 +35,10 @@ class ValidationException(Exception):
3535class Setting:
3636 """Base class of user settings"""
3737
38− def __init__(self, default_value, **kwargs):
38+ def __init__(self, default_value, locked=False, **kwargs):
3939 super().__init__()
4040 self.value = default_value
41+ self.locked = locked
4142 for key, value in kwargs.items():
4243 setattr(self, key, value)
4344
@@ -115,6 +116,9 @@ class MultipleChoiceSetting(EnumStringSetting):
115116 self.value = elements
116117
117118 def parse_form(self, data): # pylint: disable=missing-function-docstring
119+ if self.locked:
120+ return
121+
118122 self.value = []
119123 for choice in data:
120124 if choice in self.choices and choice not in self.value: # pylint: disable=no-member
@@ -149,6 +153,9 @@ class SetSetting(Setting):
149153 self.values.add(element)
150154
151155 def parse_form(self, data): # pylint: disable=missing-function-docstring
156+ if self.locked:
157+ return
158+
152159 elements = data.split(',')
153160 self.values = set(elements) # pylint: disable=attribute-defined-outside-init
154161
@@ -233,6 +240,9 @@ class SwitchableSetting(Setting):
233240 self.enabled = set(data[ENABLED].split(','))
234241
235242 def parse_form(self, items): # pylint: disable=missing-function-docstring
243+ if self.locked:
244+ return
245+
236246 items = self.transform_form_items(items)
237247 self.disabled = set() # pylint: disable=attribute-defined-outside-init
238248 self.enabled = set() # pylint: disable=attribute-defined-outside-init
@@ -317,22 +327,28 @@ class Preferences:
317327
318328 self.key_value_settings = {
319329 'categories': MultipleChoiceSetting(
320− ['general'], choices=categories + ['none']
330+ ['general'],
331+ is_locked('categories'),
332+ choices=categories + ['none']
321333 ),
322334 'language': SearchLanguageSetting(
323335 settings['search'].get('default_lang', ''),
336+ is_locked('language'),
324337 choices=list(LANGUAGE_CODES) + ['']
325338 ),
326339 'locale': EnumStringSetting(
327340 settings['ui'].get('default_locale', ''),
341+ is_locked('locale'),
328342 choices=list(settings['locales'].keys()) + ['']
329343 ),
330344 'autocomplete': EnumStringSetting(
331345 settings['search'].get('autocomplete', ''),
346+ is_locked('autocomplete'),
332347 choices=list(autocomplete.backends.keys()) + ['']
333348 ),
334349 'image_proxy': MapSetting(
335350 settings['server'].get('image_proxy', False),
351+ is_locked('image_proxy'),
336352 map={
337353 '': settings['server'].get('image_proxy', 0),
338354 '0': False,
@@ -343,10 +359,12 @@ class Preferences:
343359 ),
344360 'method': EnumStringSetting(
345361 settings['server'].get('method', 'POST'),
362+ is_locked('method'),
346363 choices=('GET', 'POST')
347364 ),
348365 'safesearch': MapSetting(
349366 settings['search'].get('safe_search', 0),
367+ is_locked('safesearch'),
350368 map={
351369 '0': 0,
352370 '1': 1,
@@ -355,10 +373,12 @@ class Preferences:
355373 ),
356374 'theme': EnumStringSetting(
357375 settings['ui'].get('default_theme', 'oscar'),
376+ is_locked('theme'),
358377 choices=themes
359378 ),
360379 'results_on_new_tab': MapSetting(
361380 settings['ui'].get('results_on_new_tab', False),
381+ is_locked('results_on_new_tab'),
362382 map={
363383 '0': False,
364384 '1': True,
@@ -367,10 +387,13 @@ class Preferences:
367387 }
368388 ),
369389 'doi_resolver': MultipleChoiceSetting(
370− ['oadoi.org'], choices=DOI_RESOLVERS
390+ ['oadoi.org'],
391+ is_locked('doi_resolver'),
392+ choices=DOI_RESOLVERS
371393 ),
372394 'oscar-style': EnumStringSetting(
373395 settings['ui'].get('theme_args', {}).get('oscar_style', 'logicodev'),
396+ is_locked('oscar-style'),
374397 choices=['', 'logicodev', 'logicodev-dark', 'pointhi']),
375398 }
376399
@@ -383,6 +406,8 @@ class Preferences:
383406 """Return preferences as URL parameters"""
384407 settings_kv = {}
385408 for k, v in self.key_value_settings.items():
409+ if v.locked:
410+ continue
386411 if isinstance(v, MultipleChoiceSetting):
387412 settings_kv[k] = ','.join(v.get_value())
388413 else:
@@ -410,6 +435,8 @@ class Preferences:
410435 """parse preferences from request (``flask.request.form``)"""
411436 for user_setting_name, user_setting in input_data.items():
412437 if user_setting_name in self.key_value_settings:
438+ if self.key_value_settings[user_setting_name].locked:
439+ continue
413440 self.key_value_settings[user_setting_name].parse(user_setting)
414441 elif user_setting_name == 'disabled_engines':
415442 self.engines.parse_cookie((input_data.get('disabled_engines', ''),
@@ -464,6 +491,8 @@ class Preferences:
464491 """Save cookie in the HTTP reponse obect
465492 """
466493 for user_setting_name, user_setting in self.key_value_settings.items():
494+ if self.key_value_settings[user_setting_name].locked:
495+ continue
467496 user_setting.save(user_setting_name, resp)
468497 self.engines.save(resp)
469498 self.plugins.save(resp)
@@ -482,3 +511,13 @@ class Preferences:
482511 break
483512
484513 return valid
514+
515+
516+def is_locked(setting_name):
517+ """Checks if a given setting name is locked by settings.yml
518+ """
519+ if 'preferences' not in settings:
520+ return False
521+ if 'lock' not in settings['preferences']:
522+ return False
523+ return setting_name in settings['preferences']['lock']