requests_connection_pool.py 文件源码

def get_session(domain_or_url):
    """
    ???????? keep-alive ?session
    :param domain_or_url: ??
    :type domain_or_url: str
    :rtype: requests.Session
    """
    domain = urllib_parse.urlsplit(domain_or_url).netloc or domain_or_url

    if domain not in pool:
        pool[domain] = []

    if not hasattr(locked_session, "sessdicts"):
        # ????????????????session
        # ???session???????, ?? pool ????, ??????????
        # ??????, ???? release_lock() ???????session
        #    ??????session?????session?
        locked_session.sessdicts = []

    if not pool[domain]:
        # ????, ???? session
        sessdict = {
            "domain": domain,
            "sessobj": requests.Session(),
        }
    else:
        # ????????????
        sessdict = pool[domain].pop()

    sessdict["active"] = time.time()

    locked_session.sessdicts.append(sessdict)

    if _gc_checkpoint < time.time() - SESSION_TTL:
        with cleaning_lock:
            clear()

    return sessdict["sessobj"]  # type: requests.Session