Source code for libcloud.http

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"""
Subclass for httplib.HTTPSConnection with optional certificate name
verification, depending on libcloud.security settings.
"""

import os
import warnings
import requests
from requests.adapters import HTTPAdapter
from requests.packages.urllib3.poolmanager import PoolManager

import libcloud.security
from libcloud.utils.py3 import urlparse, PY3


__all__ = [
    'LibcloudBaseConnection',
    'LibcloudConnection'
]

ALLOW_REDIRECTS = 1

HTTP_PROXY_ENV_VARIABLE_NAME = 'http_proxy'
HTTPS_PROXY_ENV_VARIABLE_NAME = 'https_proxy'


class SignedHTTPSAdapter(HTTPAdapter):
    def __init__(self, cert_file, key_file):
        self.cert_file = cert_file
        self.key_file = key_file
        super(SignedHTTPSAdapter, self).__init__()

    def init_poolmanager(self, connections, maxsize, block=False):
        self.poolmanager = PoolManager(
            num_pools=connections, maxsize=maxsize,
            block=block,
            cert_file=self.cert_file,
            key_file=self.key_file)


[docs]class LibcloudBaseConnection(object): """ Base connection class to inherit from. Note: This class should not be instantiated directly. """ session = None proxy_scheme = None proxy_host = None proxy_port = None proxy_username = None proxy_password = None http_proxy_used = False ca_cert = None def __init__(self): self.session = requests.Session()
[docs] def set_http_proxy(self, proxy_url): """ Set a HTTP proxy which will be used with this connection. :param proxy_url: Proxy URL (e.g. http://<hostname>:<port> without authentication and http://<username>:<password>@<hostname>:<port> for basic auth authentication information. :type proxy_url: ``str`` """ result = self._parse_proxy_url(proxy_url=proxy_url) scheme = result[0] host = result[1] port = result[2] username = result[3] password = result[4] self.proxy_scheme = scheme self.proxy_host = host self.proxy_port = port self.proxy_username = username self.proxy_password = password self.http_proxy_used = True self.session.proxies = { 'http': proxy_url, 'https': proxy_url, }
def _parse_proxy_url(self, proxy_url): """ Parse and validate a proxy URL. :param proxy_url: Proxy URL (e.g. http://hostname:3128) :type proxy_url: ``str`` :rtype: ``tuple`` (``scheme``, ``hostname``, ``port``) """ parsed = urlparse.urlparse(proxy_url) if parsed.scheme not in ('http', 'https'): raise ValueError('Only http and https proxies are supported') if not parsed.hostname or not parsed.port: raise ValueError('proxy_url must be in the following format: ' '<scheme>://<proxy host>:<proxy port>') proxy_scheme = parsed.scheme proxy_host, proxy_port = parsed.hostname, parsed.port netloc = parsed.netloc if '@' in netloc: username_password = netloc.split('@', 1)[0] split = username_password.split(':', 1) if len(split) < 2: raise ValueError('URL is in an invalid format') proxy_username, proxy_password = split[0], split[1] else: proxy_username = None proxy_password = None return (proxy_scheme, proxy_host, proxy_port, proxy_username, proxy_password) def _setup_verify(self): self.verify = libcloud.security.VERIFY_SSL_CERT def _setup_ca_cert(self, **kwargs): # simulating keyword-only argument in Python 2 ca_certs_path = kwargs.get('ca_cert', libcloud.security.CA_CERTS_PATH) if self.verify is False: pass else: if isinstance(ca_certs_path, list): msg = ( 'Providing a list of CA trusts is no longer supported ' 'since libcloud 2.0. Using the first element in the list. ' 'See http://libcloud.readthedocs.io/en/latest/other/' 'changes_in_2_0.html#providing-a-list-of-ca-trusts-is-no-' 'longer-supported') warnings.warn(msg, DeprecationWarning) self.ca_cert = ca_certs_path[0] else: self.ca_cert = ca_certs_path def _setup_signing(self, cert_file=None, key_file=None): """ Setup request signing by mounting a signing adapter to the session """ self.session.mount('https://', SignedHTTPSAdapter(cert_file, key_file))
[docs]class LibcloudConnection(LibcloudBaseConnection): timeout = None host = None response = None def __init__(self, host, port, secure=None, **kwargs): scheme = 'https' if secure is not None and secure else 'http' self.host = '{0}://{1}{2}'.format( 'https' if port == 443 else scheme, host, ":{0}".format(port) if port not in (80, 443) else "" ) # Support for HTTP(s) proxy # NOTE: We always only use a single proxy (either HTTP or HTTPS) https_proxy_url_env = os.environ.get(HTTPS_PROXY_ENV_VARIABLE_NAME, None) http_proxy_url_env = os.environ.get(HTTP_PROXY_ENV_VARIABLE_NAME, https_proxy_url_env) # Connection argument has precedence over environment variables proxy_url = kwargs.pop('proxy_url', http_proxy_url_env) self._setup_verify() self._setup_ca_cert() LibcloudBaseConnection.__init__(self) self.session.timeout = kwargs.pop('timeout', 60) if 'cert_file' in kwargs or 'key_file' in kwargs: self._setup_signing(**kwargs) if proxy_url: self.set_http_proxy(proxy_url=proxy_url) @property def verification(self): """ The option for SSL verification given to underlying requests """ return self.ca_cert if self.ca_cert is not None else self.verify
[docs] def request(self, method, url, body=None, headers=None, raw=False, stream=False): url = urlparse.urljoin(self.host, url) headers = self._normalize_headers(headers=headers) self.response = self.session.request( method=method.lower(), url=url, data=body, headers=headers, allow_redirects=ALLOW_REDIRECTS, stream=stream, verify=self.verification )
[docs] def prepared_request(self, method, url, body=None, headers=None, raw=False, stream=False): headers = self._normalize_headers(headers=headers) req = requests.Request(method, ''.join([self.host, url]), data=body, headers=headers) prepped = self.session.prepare_request(req) self.response = self.session.send( prepped, stream=stream, verify=self.ca_cert if self.ca_cert is not None else self.verify)
[docs] def getresponse(self): return self.response
[docs] def getheaders(self): # urlib decoded response body, libcloud has a bug # and will not check if content is gzipped, so let's # remove headers indicating compressed content. if 'content-encoding' in self.response.headers: del self.response.headers['content-encoding'] return self.response.headers
@property def status(self): return self.response.status_code @property def reason(self): return None if self.response.status_code > 400 else self.response.text
[docs] def connect(self): # pragma: no cover pass
[docs] def read(self): return self.response.content
[docs] def close(self): # pragma: no cover # return connection back to pool self.response.close()
def _normalize_headers(self, headers): headers = headers or {} # all headers should be strings for key, value in headers.items(): if isinstance(value, (int, float)): headers[key] = str(value) return headers
class HttpLibResponseProxy(object): """ Provides a proxy pattern around the :class:`requests.Reponse` object to a :class:`httplib.HTTPResponse` object """ def __init__(self, response): self._response = response def read(self, amt=None): return self._response.text def getheader(self, name, default=None): """ Get the contents of the header name, or default if there is no matching header. """ if name in self._response.headers.keys(): return self._response.headers[name] else: return default def getheaders(self): """ Return a list of (header, value) tuples. """ if PY3: return list(self._response.headers.items()) else: return self._response.headers.items() @property def status(self): return self._response.status_code @property def reason(self): return self._response.reason @property def version(self): # requests doesn't expose this return '11' @property def body(self): # NOTE: We use property to avoid saving whole response body into RAM # See https://github.com/apache/libcloud/pull/1132 for details return self._response.content