def should_bypass_proxies()

in aliyun-python-sdk-core/aliyunsdkcore/vendored/requests/utils.py [0:0]

• 30 lines of code
• 18 McCabe index (conditional complexity)

def should_bypass_proxies(url, no_proxy):
    """
    Returns whether we should bypass proxies or not.

    :rtype: bool
    """
    get_proxy = lambda k: os.environ.get(k) or os.environ.get(k.upper())

    # First check whether no_proxy is defined. If it is, check that the URL
    # we're getting isn't in the no_proxy list.
    no_proxy_arg = no_proxy
    if no_proxy is None:
        no_proxy = get_proxy('no_proxy')
    netloc = urlparse(url).netloc

    if no_proxy:
        # We need to check whether we match here. We need to see if we match
        # the end of the netloc, both with and without the port.
        no_proxy = (
            host for host in no_proxy.replace(' ', '').split(',') if host
        )

        ip = netloc.split(':')[0]
        if is_ipv4_address(ip):
            for proxy_ip in no_proxy:
                if is_valid_cidr(proxy_ip):
                    if address_in_network(ip, proxy_ip):
                        return True
                elif ip == proxy_ip:
                    # If no_proxy ip was defined in plain IP notation instead of cidr notation &
                    # matches the IP of the index
                    return True
        else:
            for host in no_proxy:
                if netloc.endswith(host) or netloc.split(':')[0].endswith(host):
                    # The URL does match something in no_proxy, so we don't want
                    # to apply the proxies on this URL.
                    return True

    # If the system proxy settings indicate that this URL should be bypassed,
    # don't proxy.
    # The proxy_bypass function is incredibly buggy on OS X in early versions
    # of Python 2.6, so allow this call to fail. Only catch the specific
    # exceptions we've seen, though: this call failing in other ways can reveal
    # legitimate problems.
    with set_environ('no_proxy', no_proxy_arg):
        try:
            bypass = proxy_bypass(netloc)
        except (TypeError, socket.gaierror):
            bypass = False

    if bypass:
        return True

    return False