api_utils.py 文件源码

def determine_user_agent_facing_host():
    """
    Determines the host for the active request as seen by the User-Agent
    (client), assuming proxies along the way have been being truthful.
    """

    # Request is a proxy object, and cannot be weakly-referenced; instead,
    # get a reference to true object.
    true_request = request._get_current_object()
    if true_request in HOST_CACHE:
        return HOST_CACHE[true_request]
    else:
        host = calculate_user_agent_facing_host()
        HOST_CACHE[true_request] = host
        return host