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Diffstat (limited to 'requests/packages/urllib3/poolmanager.py')
| -rw-r--r-- | requests/packages/urllib3/poolmanager.py | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/requests/packages/urllib3/poolmanager.py b/requests/packages/urllib3/poolmanager.py new file mode 100644 index 0000000..6e7377c --- /dev/null +++ b/requests/packages/urllib3/poolmanager.py @@ -0,0 +1,182 @@ +# urllib3/poolmanager.py +# Copyright 2008-2012 Andrey Petrov and contributors (see CONTRIBUTORS.txt) +# +# This module is part of urllib3 and is released under +# the MIT License: http://www.opensource.org/licenses/mit-license.php + +import logging + +from ._collections import RecentlyUsedContainer +from .connectionpool import HTTPConnectionPool, HTTPSConnectionPool +from .connectionpool import connection_from_url, port_by_scheme +from .request import RequestMethods +from .util import parse_url + + +__all__ = ['PoolManager', 'ProxyManager', 'proxy_from_url'] + + +pool_classes_by_scheme = { + 'http': HTTPConnectionPool, + 'https': HTTPSConnectionPool, +} + +log = logging.getLogger(__name__) + + +class PoolManager(RequestMethods): + """ + Allows for arbitrary requests while transparently keeping track of + necessary connection pools for you. + + :param num_pools: + Number of connection pools to cache before discarding the least + recently used pool. + + :param headers: + Headers to include with all requests, unless other headers are given + explicitly. + + :param \**connection_pool_kw: + Additional parameters are used to create fresh + :class:`urllib3.connectionpool.ConnectionPool` instances. + + Example: :: + + >>> manager = PoolManager(num_pools=2) + >>> r = manager.request('GET', 'http://google.com/') + >>> r = manager.request('GET', 'http://google.com/mail') + >>> r = manager.request('GET', 'http://yahoo.com/') + >>> len(manager.pools) + 2 + + """ + + def __init__(self, num_pools=10, headers=None, **connection_pool_kw): + RequestMethods.__init__(self, headers) + self.connection_pool_kw = connection_pool_kw + self.pools = RecentlyUsedContainer(num_pools, + dispose_func=lambda p: p.close()) + + def _new_pool(self, scheme, host, port): + """ + Create a new :class:`ConnectionPool` based on host, port and scheme. + + This method is used to actually create the connection pools handed out + by :meth:`connection_from_url` and companion methods. It is intended + to be overridden for customization. + """ + pool_cls = pool_classes_by_scheme[scheme] + return pool_cls(host, port, **self.connection_pool_kw) + + def clear(self): + """ + Empty our store of pools and direct them all to close. + + This will not affect in-flight connections, but they will not be + re-used after completion. + """ + self.pools.clear() + + def connection_from_host(self, host, port=None, scheme='http'): + """ + Get a :class:`ConnectionPool` based on the host, port, and scheme. + + If ``port`` isn't given, it will be derived from the ``scheme`` using + ``urllib3.connectionpool.port_by_scheme``. + """ + scheme = scheme or 'http' + port = port or port_by_scheme.get(scheme, 80) + + pool_key = (scheme, host, port) + + # If the scheme, host, or port doesn't match existing open connections, + # open a new ConnectionPool. + pool = self.pools.get(pool_key) + if pool: + return pool + + # Make a fresh ConnectionPool of the desired type + pool = self._new_pool(scheme, host, port) + self.pools[pool_key] = pool + return pool + + def connection_from_url(self, url): + """ + Similar to :func:`urllib3.connectionpool.connection_from_url` but + doesn't pass any additional parameters to the + :class:`urllib3.connectionpool.ConnectionPool` constructor. + + Additional parameters are taken from the :class:`.PoolManager` + constructor. + """ + u = parse_url(url) + return self.connection_from_host(u.host, port=u.port, scheme=u.scheme) + + def urlopen(self, method, url, redirect=True, **kw): + """ + Same as :meth:`urllib3.connectionpool.HTTPConnectionPool.urlopen` + with custom cross-host redirect logic and only sends the request-uri + portion of the ``url``. + + The given ``url`` parameter must be absolute, such that an appropriate + :class:`urllib3.connectionpool.ConnectionPool` can be chosen for it. + """ + u = parse_url(url) + conn = self.connection_from_host(u.host, port=u.port, scheme=u.scheme) + + kw['assert_same_host'] = False + kw['redirect'] = False + if 'headers' not in kw: + kw['headers'] = self.headers + + response = conn.urlopen(method, u.request_uri, **kw) + + redirect_location = redirect and response.get_redirect_location() + if not redirect_location: + return response + + if response.status == 303: + method = 'GET' + + log.info("Redirecting %s -> %s" % (url, redirect_location)) + kw['retries'] = kw.get('retries', 3) - 1 # Persist retries countdown + return self.urlopen(method, redirect_location, **kw) + + +class ProxyManager(RequestMethods): + """ + Given a ConnectionPool to a proxy, the ProxyManager's ``urlopen`` method + will make requests to any url through the defined proxy. The ProxyManager + class will automatically set the 'Host' header if it is not provided. + """ + + def __init__(self, proxy_pool): + self.proxy_pool = proxy_pool + + def _set_proxy_headers(self, url, headers=None): + """ + Sets headers needed by proxies: specifically, the Accept and Host + headers. Only sets headers not provided by the user. + """ + headers_ = {'Accept': '*/*'} + + host = parse_url(url).host + if host: + headers_['Host'] = host + + if headers: + headers_.update(headers) + + return headers_ + + def urlopen(self, method, url, **kw): + "Same as HTTP(S)ConnectionPool.urlopen, ``url`` must be absolute." + kw['assert_same_host'] = False + kw['headers'] = self._set_proxy_headers(url, headers=kw.get('headers')) + return self.proxy_pool.urlopen(method, url, **kw) + + +def proxy_from_url(url, **pool_kw): + proxy_pool = connection_from_url(url, **pool_kw) + return ProxyManager(proxy_pool) |