Accept-Language aware locale negotiator for Pyramid

gistfile1.py

#: Mapping of language codes send by browsers to supported dialects.
BROWSER_LANGUAGES = {
        'en-CA': 'en_CA',
        'en-GB': 'en_GB',
        'en-US': 'en_GB',
        'en': 'en_GB',
        'nl': 'nl_NL',
        'nl-NL': 'nl_NL',
        'nl-BE': 'nl_NL',
        'zh': 'zh_CN',
        'zh-CN': 'zh_CN',
        'zh-TW': 'zh_TW',
        }


def locale_negotiator(request):
    """Locale negotiator for pyramid views.

    This version differs from Pyramid's :py:func:`default_locale_negotiator
    <pyramid.i18n.default_locale_negotiator>` in that it prefers the preferred
    locale of the currently authenticated user, and has a fallback to the
    preferred languages from browser.
    """
    userid = authenticated_userid(request)
    if userid is not None:
        from s4u.dataentry.model.account import Account  # Circular import :(
        account = meta.Session.query(Account).get(userid)
        return account.locale
    locale = default_locale_negotiator(request)
    if locale is None and request.accept_language:
        locale = request.accept_language.best_match(BROWSER_LANGUAGES)
        locale = BROWSER_LANGUAGES.get(locale)
    return locale