serving cache busted assets without renaming files on disk

notfound.py

_static_regex = re.compile(
    r'''
    (?P<root>/static/[a-zA-Z0-9._/-]+)
    -
    (?P<buster>[a-fA-F0-9]+)
    (?P<ext>\.[a-zA-Z0-9]+)
    $''',
    re.VERBOSE,
)

def RemoveCacheBustTokenNotFoundViewFactory(wrapped):
    def wrapper(context, request):
        m = _static_regex.match(request.path_info)
        if m is not None and request.method in ('GET', 'OPTIONS', 'HEAD'):
            path = m.group('root') + m.group('ext')
            subreq = request.blank(
                path,
                base_url=request.application_url,
            )
            try:
                response = request.invoke_subrequest(subreq, use_tweens=False)
                response.cache_max_age = 10 * 365 * 34 * 3600
                return response
            except Exception:
                pass
        return wrapped(context, request)
    return wrapper

@notfound_view_config(
    decorator=[
        RemoveCacheBustTokenNotFoundViewFactory,
    ],
)
def notfound_view(exc, request):
    return exc