Python django.utils.translation 模块，LANGUAGE_SESSION_KEY 实例源码

def logout(request):
    """
    Removes the authenticated user's ID from the request and flushes their
    session data.
    """
    # Dispatch the signal before the user is logged out so the receivers have a
    # chance to find out *who* logged out.
    user = getattr(request, 'user', None)
    if hasattr(user, 'is_authenticated') and not user.is_authenticated():
        user = None
    user_logged_out.send(sender=user.__class__, request=request, user=user)

    # remember language choice saved to session
    language = request.session.get(LANGUAGE_SESSION_KEY)

    request.session.flush()

    if language is not None:
        request.session[LANGUAGE_SESSION_KEY] = language

    if hasattr(request, 'user'):
        from django.contrib.auth.models import AnonymousUser
        request.user = AnonymousUser()

def logout(request):
    """
    Removes the authenticated user's ID from the request and flushes their
    session data.
    """
    # Dispatch the signal before the user is logged out so the receivers have a
    # chance to find out *who* logged out.
    user = getattr(request, 'user', None)
    if hasattr(user, 'is_authenticated') and not user.is_authenticated:
        user = None
    user_logged_out.send(sender=user.__class__, request=request, user=user)

    # remember language choice saved to session
    language = request.session.get(LANGUAGE_SESSION_KEY)

    request.session.flush()

    if language is not None:
        request.session[LANGUAGE_SESSION_KEY] = language

    if hasattr(request, 'user'):
        from django.contrib.auth.models import AnonymousUser
        request.user = AnonymousUser()

def logout(request):
    """
    Removes the authenticated user's ID from the request and flushes their
    session data.
    """
    # Dispatch the signal before the user is logged out so the receivers have a
    # chance to find out *who* logged out.
    user = getattr(request, 'user', None)
    if hasattr(user, 'is_authenticated') and not user.is_authenticated:
        user = None
    user_logged_out.send(sender=user.__class__, request=request, user=user)

    # remember language choice saved to session
    language = request.session.get(LANGUAGE_SESSION_KEY)

    request.session.flush()

    if language is not None:
        request.session[LANGUAGE_SESSION_KEY] = language

    if hasattr(request, 'user'):
        from django.contrib.auth.models import AnonymousUser
        request.user = AnonymousUser()

def logout(request):
    """
    Removes the authenticated user's ID from the request and flushes their
    session data.
    """
    # Dispatch the signal before the user is logged out so the receivers have a
    # chance to find out *who* logged out.
    user = getattr(request, 'user', None)
    if hasattr(user, 'is_authenticated') and not user.is_authenticated:
        user = None
    user_logged_out.send(sender=user.__class__, request=request, user=user)

    # remember language choice saved to session
    language = request.session.get(LANGUAGE_SESSION_KEY)

    request.session.flush()

    if language is not None:
        request.session[LANGUAGE_SESSION_KEY] = language

    if hasattr(request, 'user'):
        from django.contrib.auth.models import AnonymousUser
        request.user = AnonymousUser()

def logout(request):
    """
    Removes the authenticated user's ID from the request and flushes their
    session data.
    """
    # Dispatch the signal before the user is logged out so the receivers have a
    # chance to find out *who* logged out.
    user = getattr(request, 'user', None)
    if hasattr(user, 'is_authenticated') and not user.is_authenticated:
        user = None
    user_logged_out.send(sender=user.__class__, request=request, user=user)

    # remember language choice saved to session
    language = request.session.get(LANGUAGE_SESSION_KEY)

    request.session.flush()

    if language is not None:
        request.session[LANGUAGE_SESSION_KEY] = language

    if hasattr(request, 'user'):
        from django.contrib.auth.models import AnonymousUser
        request.user = AnonymousUser()

def logout(request):
    """
    Removes the authenticated user's ID from the request and flushes their
    session data.
    """
    # Dispatch the signal before the user is logged out so the receivers have a
    # chance to find out *who* logged out.
    user = getattr(request, 'user', None)
    if hasattr(user, 'is_authenticated') and not user.is_authenticated():
        user = None
    user_logged_out.send(sender=user.__class__, request=request, user=user)

    # remember language choice saved to session
    language = request.session.get(LANGUAGE_SESSION_KEY)

    request.session.flush()

    if language is not None:
        request.session[LANGUAGE_SESSION_KEY] = language

    if hasattr(request, 'user'):
        from django.contrib.auth.models import AnonymousUser
        request.user = AnonymousUser()

def logout(request):
    """
    Removes the authenticated user's ID from the request and flushes their
    session data.
    """
    # Dispatch the signal before the user is logged out so the receivers have a
    # chance to find out *who* logged out.
    user = getattr(request, 'user', None)
    if hasattr(user, 'is_authenticated') and not user.is_authenticated():
        user = None
    user_logged_out.send(sender=user.__class__, request=request, user=user)

    # remember language choice saved to session
    language = request.session.get(LANGUAGE_SESSION_KEY)

    request.session.flush()

    if language is not None:
        request.session[LANGUAGE_SESSION_KEY] = language

    if hasattr(request, 'user'):
        from django.contrib.auth.models import AnonymousUser
        request.user = AnonymousUser()

def logout(request):
    """
    Removes the authenticated user's ID from the request and flushes their
    session data.
    """
    # Dispatch the signal before the user is logged out so the receivers have a
    # chance to find out *who* logged out.
    user = getattr(request, 'user', None)
    if hasattr(user, 'is_authenticated') and not user.is_authenticated():
        user = None
    user_logged_out.send(sender=user.__class__, request=request, user=user)

    # remember language choice saved to session
    language = request.session.get(LANGUAGE_SESSION_KEY)

    request.session.flush()

    if language is not None:
        request.session[LANGUAGE_SESSION_KEY] = language

    if hasattr(request, 'user'):
        from django.contrib.auth.models import AnonymousUser
        request.user = AnonymousUser()

def logout(request):
    """
    Removes the authenticated user's ID from the request and flushes their
    session data.
    """
    # Dispatch the signal before the user is logged out so the receivers have a
    # chance to find out *who* logged out.
    user = getattr(request, 'user', None)
    if hasattr(user, 'is_authenticated') and not user.is_authenticated():
        user = None
    user_logged_out.send(sender=user.__class__, request=request, user=user)

    # remember language choice saved to session
    language = request.session.get(LANGUAGE_SESSION_KEY)

    request.session.flush()

    if language is not None:
        request.session[LANGUAGE_SESSION_KEY] = language

    if hasattr(request, 'user'):
        from django.contrib.auth.models import AnonymousUser
        request.user = AnonymousUser()

def logout(request):
    """
    Removes the authenticated user's ID from the request and flushes their
    session data.
    """
    # Dispatch the signal before the user is logged out so the receivers have a
    # chance to find out *who* logged out.
    user = getattr(request, 'user', None)
    if hasattr(user, 'is_authenticated') and not user.is_authenticated():
        user = None
    user_logged_out.send(sender=user.__class__, request=request, user=user)

    # remember language choice saved to session
    language = request.session.get(LANGUAGE_SESSION_KEY)

    request.session.flush()

    if language is not None:
        request.session[LANGUAGE_SESSION_KEY] = language

    if hasattr(request, 'user'):
        from django.contrib.auth.models import AnonymousUser
        request.user = AnonymousUser()

def setlang(request):
    """
    Sets a user's language preference and redirects to a given URL or, by default, back to the previous page.
    """
    next = request.REQUEST.get('next')
    if not is_safe_url(url=next, host=request.get_host()):
        next = request.META.get('HTTP_REFERER')
        if not is_safe_url(url=next, host=request.get_host()):
            next = '/'
    response = redirect(next)

    lang_code = request.REQUEST.get('language', None)
    if lang_code and check_for_language(lang_code):
        if hasattr(request, 'session'):
            request.session[LANGUAGE_SESSION_KEY] = lang_code
        else:
            response.set_cookie(settings.LANGUAGE_COOKIE_NAME, lang_code,
                                max_age=settings.LANGUAGE_COOKIE_AGE,
                                path=settings.LANGUAGE_COOKIE_PATH,
                                domain=settings.LANGUAGE_COOKIE_DOMAIN)

    return response

def logout(request):
    """
    Removes the authenticated user's ID from the request and flushes their
    session data.
    """
    # Dispatch the signal before the user is logged out so the receivers have a
    # chance to find out *who* logged out.
    user = getattr(request, 'user', None)
    if hasattr(user, 'is_authenticated') and not user.is_authenticated:
        user = None
    user_logged_out.send(sender=user.__class__, request=request, user=user)

    # remember language choice saved to session
    language = request.session.get(LANGUAGE_SESSION_KEY)

    request.session.flush()

    if language is not None:
        request.session[LANGUAGE_SESSION_KEY] = language

    if hasattr(request, 'user'):
        from django.contrib.auth.models import AnonymousUser
        request.user = AnonymousUser()

def logout(request):
    """
    Removes the authenticated user's ID from the request and flushes their
    session data.
    """
    # Dispatch the signal before the user is logged out so the receivers have a
    # chance to find out *who* logged out.
    user = getattr(request, 'user', None)
    if hasattr(user, 'is_authenticated') and not user.is_authenticated:
        user = None
    user_logged_out.send(sender=user.__class__, request=request, user=user)

    # remember language choice saved to session
    language = request.session.get(LANGUAGE_SESSION_KEY)

    request.session.flush()

    if language is not None:
        request.session[LANGUAGE_SESSION_KEY] = language

    if hasattr(request, 'user'):
        from django.contrib.auth.models import AnonymousUser
        request.user = AnonymousUser()

def logout(request):
    """
    Removes the authenticated user's ID from the request and flushes their
    session data.
    """
    # Dispatch the signal before the user is logged out so the receivers have a
    # chance to find out *who* logged out.
    user = getattr(request, 'user', None)
    if hasattr(user, 'is_authenticated') and not user.is_authenticated:
        user = None
    user_logged_out.send(sender=user.__class__, request=request, user=user)

    # remember language choice saved to session
    language = request.session.get(LANGUAGE_SESSION_KEY)

    request.session.flush()

    if language is not None:
        request.session[LANGUAGE_SESSION_KEY] = language

    if hasattr(request, 'user'):
        from django.contrib.auth.models import AnonymousUser
        request.user = AnonymousUser()

def logout(request):
    """
    Removes the authenticated user's ID from the request and flushes their
    session data.
    """
    # Dispatch the signal before the user is logged out so the receivers have a
    # chance to find out *who* logged out.
    user = getattr(request, 'user', None)
    if hasattr(user, 'is_authenticated') and not user.is_authenticated:
        user = None
    user_logged_out.send(sender=user.__class__, request=request, user=user)

    # remember language choice saved to session
    language = request.session.get(LANGUAGE_SESSION_KEY)

    request.session.flush()

    if language is not None:
        request.session[LANGUAGE_SESSION_KEY] = language

    if hasattr(request, 'user'):
        from django.contrib.auth.models import AnonymousUser
        request.user = AnonymousUser()

def test_session_language(self):
        page = api.create_page("home", "nav_playground.html", "en", published=True)
        api.create_title('fr', "home", page)
        page.publish('fr')
        page.publish('en')
        response = self.client.get('/')
        self.assertEqual(response.status_code, 302)
        self.assertRedirects(response, '/en/')
        engine = import_module(settings.SESSION_ENGINE)
        store = engine.SessionStore()
        store.save()  # we need to make load() work, or the cookie is worthless
        self.client.cookies[settings.SESSION_COOKIE_NAME] = store.session_key

        #   ugly and long set of session
        session = self.client.session
        session[LANGUAGE_SESSION_KEY] = 'fr'
        session.save()
        response = self.client.get('/')
        self.assertEqual(response.status_code, 302)
        self.assertRedirects(response, '/fr/')
        self.client.get('/en/')
        self.assertEqual(self.client.session[LANGUAGE_SESSION_KEY], 'en')
        response = self.client.get('/')
        self.assertEqual(response.status_code, 302)
        self.assertRedirects(response, '/en/')

def logout(request):
    """
    Removes the authenticated user's ID from the request and flushes their
    session data.
    """
    # Dispatch the signal before the user is logged out so the receivers have a
    # chance to find out *who* logged out.
    user = getattr(request, 'user', None)
    if hasattr(user, 'is_authenticated') and not user.is_authenticated():
        user = None
    user_logged_out.send(sender=user.__class__, request=request, user=user)

    # remember language choice saved to session
    language = request.session.get(LANGUAGE_SESSION_KEY)

    request.session.flush()

    if language is not None:
        request.session[LANGUAGE_SESSION_KEY] = language

    if hasattr(request, 'user'):
        from django.contrib.auth.models import AnonymousUser
        request.user = AnonymousUser()

def logout(request):
    """
    Removes the authenticated user's ID from the request and flushes their
    session data.
    """
    # Dispatch the signal before the user is logged out so the receivers have a
    # chance to find out *who* logged out.
    user = getattr(request, 'user', None)
    if hasattr(user, 'is_authenticated') and not user.is_authenticated:
        user = None
    user_logged_out.send(sender=user.__class__, request=request, user=user)

    # remember language choice saved to session
    language = request.session.get(LANGUAGE_SESSION_KEY)

    request.session.flush()

    if language is not None:
        request.session[LANGUAGE_SESSION_KEY] = language

    if hasattr(request, 'user'):
        from django.contrib.auth.models import AnonymousUser
        request.user = AnonymousUser()

def logout(request):
    """
    Removes the authenticated user's ID from the request and flushes their
    session data.
    """
    # Dispatch the signal before the user is logged out so the receivers have a
    # chance to find out *who* logged out.
    user = getattr(request, 'user', None)
    if hasattr(user, 'is_authenticated') and not user.is_authenticated():
        user = None
    user_logged_out.send(sender=user.__class__, request=request, user=user)

    # remember language choice saved to session
    language = request.session.get(LANGUAGE_SESSION_KEY)

    request.session.flush()

    if language is not None:
        request.session[LANGUAGE_SESSION_KEY] = language

    if hasattr(request, 'user'):
        from django.contrib.auth.models import AnonymousUser
        request.user = AnonymousUser()

def logout(request):
    """
    Removes the authenticated user's ID from the request and flushes their
    session data.
    """
    # Dispatch the signal before the user is logged out so the receivers have a
    # chance to find out *who* logged out.
    user = getattr(request, 'user', None)
    if hasattr(user, 'is_authenticated') and not user.is_authenticated():
        user = None
    user_logged_out.send(sender=user.__class__, request=request, user=user)

    # remember language choice saved to session
    language = request.session.get(LANGUAGE_SESSION_KEY)

    request.session.flush()

    if language is not None:
        request.session[LANGUAGE_SESSION_KEY] = language

    if hasattr(request, 'user'):
        from django.contrib.auth.models import AnonymousUser
        request.user = AnonymousUser()

def logout(request):
    """
    Removes the authenticated user's ID from the request and flushes their
    session data.
    """
    # Dispatch the signal before the user is logged out so the receivers have a
    # chance to find out *who* logged out.
    user = getattr(request, 'user', None)
    if hasattr(user, 'is_authenticated') and not user.is_authenticated:
        user = None
    user_logged_out.send(sender=user.__class__, request=request, user=user)

    # remember language choice saved to session
    language = request.session.get(LANGUAGE_SESSION_KEY)

    request.session.flush()

    if language is not None:
        request.session[LANGUAGE_SESSION_KEY] = language

    if hasattr(request, 'user'):
        from django.contrib.auth.models import AnonymousUser
        request.user = AnonymousUser()

def logout(request):
    """
    Removes the authenticated user's ID from the request and flushes their
    session data.
    """
    # Dispatch the signal before the user is logged out so the receivers have a
    # chance to find out *who* logged out.
    user = getattr(request, 'user', None)
    if hasattr(user, 'is_authenticated') and not user.is_authenticated:
        user = None
    user_logged_out.send(sender=user.__class__, request=request, user=user)

    # remember language choice saved to session
    language = request.session.get(LANGUAGE_SESSION_KEY)

    request.session.flush()

    if language is not None:
        request.session[LANGUAGE_SESSION_KEY] = language

    if hasattr(request, 'user'):
        from django.contrib.auth.models import AnonymousUser
        request.user = AnonymousUser()

def logout(request):
    """
    Removes the authenticated user's ID from the request and flushes their
    session data.
    """
    # Dispatch the signal before the user is logged out so the receivers have a
    # chance to find out *who* logged out.
    user = getattr(request, 'user', None)
    if hasattr(user, 'is_authenticated') and not user.is_authenticated:
        user = None
    user_logged_out.send(sender=user.__class__, request=request, user=user)

    # remember language choice saved to session
    language = request.session.get(LANGUAGE_SESSION_KEY)

    request.session.flush()

    if language is not None:
        request.session[LANGUAGE_SESSION_KEY] = language

    if hasattr(request, 'user'):
        from django.contrib.auth.models import AnonymousUser
        request.user = AnonymousUser()

def logout(request):
    """
    Removes the authenticated user's ID from the request and flushes their
    session data.
    """
    # Dispatch the signal before the user is logged out so the receivers have a
    # chance to find out *who* logged out.
    user = getattr(request, 'user', None)
    if hasattr(user, 'is_authenticated') and not user.is_authenticated():
        user = None
    user_logged_out.send(sender=user.__class__, request=request, user=user)

    # remember language choice saved to session
    language = request.session.get(LANGUAGE_SESSION_KEY)

    request.session.flush()

    if language is not None:
        request.session[LANGUAGE_SESSION_KEY] = language

    if hasattr(request, 'user'):
        from django.contrib.auth.models import AnonymousUser
        request.user = AnonymousUser()

def logout(request):
    """
    Removes the authenticated user's ID from the request and flushes their
    session data.
    """
    # Dispatch the signal before the user is logged out so the receivers have a
    # chance to find out *who* logged out.
    user = getattr(request, 'user', None)
    if hasattr(user, 'is_authenticated') and not user.is_authenticated():
        user = None
    user_logged_out.send(sender=user.__class__, request=request, user=user)

    # remember language choice saved to session
    language = request.session.get(LANGUAGE_SESSION_KEY)

    request.session.flush()

    if language is not None:
        request.session[LANGUAGE_SESSION_KEY] = language

    if hasattr(request, 'user'):
        from django.contrib.auth.models import AnonymousUser
        request.user = AnonymousUser()

def logout(request):
    """
    Removes the authenticated user's ID from the request and flushes their
    session data.
    """
    # Dispatch the signal before the user is logged out so the receivers have a
    # chance to find out *who* logged out.
    user = getattr(request, 'user', None)
    if hasattr(user, 'is_authenticated') and not user.is_authenticated:
        user = None
    user_logged_out.send(sender=user.__class__, request=request, user=user)

    # remember language choice saved to session
    language = request.session.get(LANGUAGE_SESSION_KEY)

    request.session.flush()

    if language is not None:
        request.session[LANGUAGE_SESSION_KEY] = language

    if hasattr(request, 'user'):
        from django.contrib.auth.models import AnonymousUser
        request.user = AnonymousUser()

def logout(request):
    """
    Removes the authenticated user's ID from the request and flushes their
    session data.
    """
    # Dispatch the signal before the user is logged out so the receivers have a
    # chance to find out *who* logged out.
    user = getattr(request, 'user', None)
    if hasattr(user, 'is_authenticated') and not user.is_authenticated():
        user = None
    user_logged_out.send(sender=user.__class__, request=request, user=user)

    # remember language choice saved to session
    language = request.session.get(LANGUAGE_SESSION_KEY)

    request.session.flush()

    if language is not None:
        request.session[LANGUAGE_SESSION_KEY] = language

    if hasattr(request, 'user'):
        from django.contrib.auth.models import AnonymousUser
        request.user = AnonymousUser()

def post(self, request):
        form = self.form_class(data=request.POST)

        # NOTE: authenticate is already called internally in form.clean
        if form.is_valid():
            username_or_email = request.POST['username']
            password = request.POST['password']
            # NOTE: authenticate is already called internally in form.clean so there is no need to verify the result
            user = authenticate(username=username_or_email, password=password)
            login(request, user)

            request.session[translation.LANGUAGE_SESSION_KEY] = user.language
            redirect_to = request.POST.get('next', request.GET.get('next', reverse('landing_page:home')))
            redirect_to = (redirect_to
                           if is_safe_url(redirect_to, request.get_host())
                           else reverse('landing_page:home'))
            if redirect_to == "":
                return HttpResponseRedirect(reverse("landing_page:home"))
            else:
                return HttpResponseRedirect(redirect_to)

        return render(request, 'registration/login.html', {'form': form})

def logout(request):
    """
    Removes the authenticated user's ID from the request and flushes their
    session data.
    """
    # Dispatch the signal before the user is logged out so the receivers have a
    # chance to find out *who* logged out.
    user = getattr(request, 'user', None)
    if hasattr(user, 'is_authenticated') and not user.is_authenticated():
        user = None
    user_logged_out.send(sender=user.__class__, request=request, user=user)

    # remember language choice saved to session
    language = request.session.get(LANGUAGE_SESSION_KEY)

    request.session.flush()

    if language is not None:
        request.session[LANGUAGE_SESSION_KEY] = language

    if hasattr(request, 'user'):
        from django.contrib.auth.models import AnonymousUser
        request.user = AnonymousUser()

def logout(request):
    """
    Removes the authenticated user's ID from the request and flushes their
    session data.
    """
    # Dispatch the signal before the user is logged out so the receivers have a
    # chance to find out *who* logged out.
    user = getattr(request, 'user', None)
    if hasattr(user, 'is_authenticated') and not user.is_authenticated():
        user = None
    user_logged_out.send(sender=user.__class__, request=request, user=user)

    # remember language choice saved to session
    language = request.session.get(LANGUAGE_SESSION_KEY)

    request.session.flush()

    if language is not None:
        request.session[LANGUAGE_SESSION_KEY] = language

    if hasattr(request, 'user'):
        from django.contrib.auth.models import AnonymousUser
        request.user = AnonymousUser()

def get_lang_from_session(request, supported):
    if hasattr(request, 'session'):
        lang_code = request.session.get(LANGUAGE_SESSION_KEY, None)
        if lang_code and lang_code in supported:
            return lang_code

    return None

def set_language(request):
    """
    Redirect to a given url while setting the chosen language in the
    session or cookie. The url and the language code need to be
    specified in the request parameters.
    Since this view changes how the user will see the rest of the site, it must
    only be accessed as a POST request. If called as a GET request, it will
    redirect to the page in the request (the 'next' parameter) without changing
    any state.
    """
    next = request.POST.get('next', request.GET.get('next'))
    if not is_safe_url(url=next, host=request.get_host()):
        next = request.META.get('HTTP_REFERER')
        if not is_safe_url(url=next, host=request.get_host()):
            next = '/'
    response = http.HttpResponseRedirect(next)
    if request.method == 'POST':
        lang_code = request.POST.get(LANGUAGE_QUERY_PARAMETER)
        if lang_code and check_for_language(lang_code):
            next_trans = translate_url(next, lang_code)
            if next_trans != next:
                response = http.HttpResponseRedirect(next_trans)
            if hasattr(request, 'session'):
                request.session[LANGUAGE_SESSION_KEY] = lang_code
            # Always set cookie
            response.set_cookie(settings.LANGUAGE_COOKIE_NAME, lang_code,
                                max_age=settings.LANGUAGE_COOKIE_AGE,
                                path=settings.LANGUAGE_COOKIE_PATH,
                                domain=settings.LANGUAGE_COOKIE_DOMAIN)
    return response

def activate_locale(self, request):
        """
        Save language and timezone settings from profile into session.
        The settings are read by django middleware.
        """
        request.session[LANGUAGE_SESSION_KEY] = str(self.language)
        request.session[settings.TIMEZONE_SESSION_KEY] = str(self.timezone)

def get(self, request, *args, **kwargs):
        current_language = get_language()
        request.session[LANGUAGE_SESSION_KEY] = current_language

        return super(MoviesListView, self).get(request, *args, **kwargs)

def get(self, request, *args, **kwargs):
        current_language = get_language()
        request.session[LANGUAGE_SESSION_KEY] = current_language

        return super(MoviesListView, self).get(request, *args, **kwargs)

def process_response(self, request, response):
        language = get_language()
        if hasattr(request, 'session'):
            session_language = request.session.get(LANGUAGE_SESSION_KEY, None)
            if session_language and not session_language == language:
                request.session[LANGUAGE_SESSION_KEY] = language
                request.session.save()
        if settings.LANGUAGE_COOKIE_NAME in request.COOKIES and \
                        request.COOKIES[settings.LANGUAGE_COOKIE_NAME] == language:
            return response
        max_age = 365 * 24 * 60 * 60  # 10 years
        expires = datetime.datetime.utcnow() + datetime.timedelta(seconds=max_age)
        response.set_cookie(settings.LANGUAGE_COOKIE_NAME, language, expires=expires)
        return response

def user_time(request):
    try:
        stprofile = StProfile.objects.get(user=request.user)
        timezone.activate(stprofile.time_zone)
        request.session['django_timezone'] = stprofile.time_zone
    except:
        pass
    messages.success(request, _(u"You have successfully logged in as %s") % request.user.username)
    try:
        translation.activate(stprofile.language)
        request.session[translation.LANGUAGE_SESSION_KEY] = stprofile.language
    except:
        pass
    return HttpResponseRedirect(reverse('home'))

def get_language_from_request(request):  # noqa complexity-16
    """
    Analyzes the request to find what language the user wants the system to
    show. Only languages listed in settings.LANGUAGES are taken into account.
    If the user requests a sublanguage where we have a main language, we send
    out the main language.
    If check_path is True, the URL path prefix will be checked for a language
    code, otherwise this is skipped for backwards compatibility.
    """
    global DEVICE_LANGUAGE

    supported_lang_codes = get_languages()

    if hasattr(request, 'session'):
        lang_code = request.session.get(LANGUAGE_SESSION_KEY)
        if lang_code in supported_lang_codes and lang_code is not None and check_for_language(lang_code):
            return lang_code

    lang_code = request.COOKIES.get(settings.LANGUAGE_COOKIE_NAME)

    try:
        return get_supported_language_variant(lang_code)
    except LookupError:
        pass

    accept = request.META.get('HTTP_ACCEPT_LANGUAGE', '')
    for accept_lang, unused in parse_accept_lang_header(accept):
        if accept_lang == '*':
            break

        if not language_code_re.search(accept_lang):
            continue

        try:
            return get_supported_language_variant(accept_lang)
        except LookupError:
            continue

    try:
        if DEVICE_LANGUAGE is None:
            DEVICE_LANGUAGE = DeviceSettings.objects.get().language_id
        return get_supported_language_variant(DEVICE_LANGUAGE)
    except (DeviceSettings.DoesNotExist, LookupError):
        pass

    try:
        return get_supported_language_variant(settings.LANGUAGE_CODE)
    except LookupError:
        return settings.LANGUAGE_CODE

def get_language_from_request(request, check_path=False):
    """
    Analyzes the request to find what language the user wants the system to
    show. Only languages listed in settings.LANGUAGES are taken into account.
    If the user requests a sublanguage where we have a main language, we send
    out the main language.

    If check_path is True, the URL path prefix will be checked for a language
    code, otherwise this is skipped for backwards compatibility.
    """
    if check_path:
        lang_code = get_language_from_path(request.path_info)
        if lang_code is not None:
            return lang_code

    supported_lang_codes = get_languages()

    if hasattr(request, 'session'):
        lang_code = request.session.get(LANGUAGE_SESSION_KEY)
        if lang_code in supported_lang_codes and lang_code is not None and check_for_language(lang_code):
            return lang_code

    lang_code = request.COOKIES.get(settings.LANGUAGE_COOKIE_NAME)

    try:
        return get_supported_language_variant(lang_code)
    except LookupError:
        pass

    accept = request.META.get('HTTP_ACCEPT_LANGUAGE', '')
    for accept_lang, unused in parse_accept_lang_header(accept):
        if accept_lang == '*':
            break

        if not language_code_re.search(accept_lang):
            continue

        try:
            return get_supported_language_variant(accept_lang)
        except LookupError:
            continue

    try:
        return get_supported_language_variant(settings.LANGUAGE_CODE)
    except LookupError:
        return settings.LANGUAGE_CODE

def get_language_from_request(request, check_path=False):
    """
    Analyzes the request to find what language the user wants the system to
    show. Only languages listed in settings.LANGUAGES are taken into account.
    If the user requests a sublanguage where we have a main language, we send
    out the main language.

    If check_path is True, the URL path prefix will be checked for a language
    code, otherwise this is skipped for backwards compatibility.
    """
    if check_path:
        lang_code = get_language_from_path(request.path_info)
        if lang_code is not None:
            return lang_code

    supported_lang_codes = get_languages()

    if hasattr(request, 'session'):
        lang_code = request.session.get(LANGUAGE_SESSION_KEY)
        if lang_code in supported_lang_codes and lang_code is not None and check_for_language(lang_code):
            return lang_code

    lang_code = request.COOKIES.get(settings.LANGUAGE_COOKIE_NAME)

    try:
        return get_supported_language_variant(lang_code)
    except LookupError:
        pass

    accept = request.META.get('HTTP_ACCEPT_LANGUAGE', '')
    for accept_lang, unused in parse_accept_lang_header(accept):
        if accept_lang == '*':
            break

        if not language_code_re.search(accept_lang):
            continue

        try:
            return get_supported_language_variant(accept_lang)
        except LookupError:
            continue

    try:
        return get_supported_language_variant(settings.LANGUAGE_CODE)
    except LookupError:
        return settings.LANGUAGE_CODE

def user_preference(request):

    current_user = User.objects.get(username=request.user.username)

    if request.method == 'POST':

        if request.POST.get('cancel_button'):
            messages.warning(request, _(u"Changing user settings canceled"))
            return HttpResponseRedirect(reverse('home'))

        else:
            errors = {}
            stprofile = StProfile.objects.get_or_create(user=current_user)[0]

            form_first_name=request.POST.get('first_name', '').strip()
            current_user.first_name = form_first_name

            form_last_name=request.POST.get('last_name', '').strip()
            current_user.last_name = form_last_name

            form_email=request.POST.get('email', '').strip()
            users_same_email = User.objects.filter(email=form_email)
            if len(users_same_email) > 0 and current_user.email != form_email:
                current_user.email = form_email
                errors['email'] = _(u"This email address is already in use." +
                    " Please enter a different email address.")
            elif len(form_email) > 0:
                try:
                    validate_email(form_email)
                except ValidationError:
                    errors['email'] = _(u"Enter a valid email address")
                else:
                    current_user.email = form_email

            form_language=request.POST.get('lang')
            if stprofile.language != form_language:
                stprofile.language = form_language
                translation.activate(form_language)
                request.session[translation.LANGUAGE_SESSION_KEY] = form_language

            form_time_zone=request.POST.get('time_zone')
            if stprofile.time_zone != form_time_zone:
                stprofile.time_zone = form_time_zone
                timezone.activate(form_time_zone)
                request.session['django_timezone'] = form_time_zone

            if errors:
                messages.error(request, _(u'Please, correct the following errors'))
                return render(request, 'students/user_preference.html',
                    {'current_user': current_user, 'timezones': pytz.common_timezones, 'errors': errors})

            current_user.save()
            stprofile.save()

            messages.success(request, _(u"User settings changed successfully"))
            return HttpResponseRedirect(reverse('home'))

    else:
        return render(request, 'students/user_preference.html',
            {'current_user': current_user, 'timezones': pytz.common_timezones})

def post(self, request, *args, **kwargs):
        self.object = self.get_object()

        # set language key
        request.session[translation.LANGUAGE_SESSION_KEY] = request.POST['language']

        # if a new avatar image was set, save it as the 'old' one
        self.avatar_kwargs = {'old_avatar_name': self.object.avatar.name}

        # Changing the email address should not be possible without entering the correct password!!
        # Normally this is a check one want in the clean-methods of those forms, but there it is not possible to access
        # elements of other forms, so this is a dirty workaround.
        # TODO maybe it is possible to provide this error to the respective clean-functions
        username = self.kwargs.get('username')
        # this should make this situation TOCTOU-safe
        # in case it doesn't try to use select_for_update()
        with transaction.atomic():
            # NOTE: this has to be part of the atomic block!
            current_user = get_user_model().objects.get(username=username)
            old_email = current_user.email
            forms = request.POST
            new_email = forms['email']
            wrong_password = False

            if old_email != new_email:
                try:
                    provided_password = forms['old_password']
                except:
                    provided_password = None

                if(provided_password is None or provided_password == "" or
                   authenticate(username=username, password=provided_password) is None):
                    wrong_password = True

        # NOTE: in this case we shall not call save (super)
        if wrong_password:
            messages.add_message(request, messages.ERROR,
                                 _('You can not change the email-address without entering the correct password.' +
                                   'All changes have been discarded!'))
            # TODO copy elements? - this might be some pain because we have to split those elements on both forms
            return super(EditProfilePageView, self).get(request, *args, **kwargs)

        response = super(EditProfilePageView, self).post(request, *args, **kwargs)

        current_user = get_user_model().objects.get(username=username)

        if response.status_code == 200:
            messages.add_message(request, messages.ERROR,
                                 _('Something went wrong, one or more field credentials are not fulfilled'))
        else:
            messages.add_message(request, messages.SUCCESS, _('Profile successfully edited.'))
        return response