python-ceilometerclient/ceilometerclient/common/http.py

314 lines
11 KiB
Python

# Copyright 2012 OpenStack Foundation
# All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
import copy
import hashlib
import logging
import os
import socket
try:
import ssl
except ImportError:
# TODO(bcwaldon): Handle this failure more gracefully
pass
try:
import json
except ImportError:
import simplejson as json
import six
from six.moves import http_client as httplib # noqa
from six.moves import urllib
from ceilometerclient import exc
LOG = logging.getLogger(__name__)
USER_AGENT = 'python-ceilometerclient'
CHUNKSIZE = 1024 * 64 # 64kB
SENSITIVE_HEADERS = ('X-Auth-Token',)
class HTTPClient(object):
def __init__(self, endpoint, **kwargs):
self.endpoint = endpoint
self.auth_token = kwargs.get('token')
self.connection_params = self.get_connection_params(endpoint, **kwargs)
self.proxy_url = self.get_proxy_url()
@staticmethod
def get_connection_params(endpoint, **kwargs):
parts = urllib.parse.urlparse(endpoint)
_args = (parts.hostname, parts.port, parts.path)
_kwargs = {'timeout': (float(kwargs.get('timeout'))
if kwargs.get('timeout') else 600)}
if parts.scheme == 'https':
_class = VerifiedHTTPSConnection
_kwargs['cacert'] = kwargs.get('cacert', None)
_kwargs['cert_file'] = kwargs.get('cert_file', None)
_kwargs['key_file'] = kwargs.get('key_file', None)
_kwargs['insecure'] = kwargs.get('insecure', False)
elif parts.scheme == 'http':
_class = httplib.HTTPConnection
else:
msg = 'Unsupported scheme: %s' % parts.scheme
raise exc.InvalidEndpoint(msg)
return (_class, _args, _kwargs)
def get_connection(self):
_class = self.connection_params[0]
try:
if self.proxy_url:
proxy_parts = urllib.parse.urlparse(self.proxy_url)
return _class(proxy_parts.hostname, proxy_parts.port,
**self.connection_params[2])
else:
return _class(*self.connection_params[1][0:2],
**self.connection_params[2])
except httplib.InvalidURL:
raise exc.InvalidEndpoint()
def safe_header(self, name, value):
if name in SENSITIVE_HEADERS:
# because in python3 byte string handling is ... ug
v = value.encode('utf-8')
h = hashlib.sha1(v)
d = h.hexdigest()
return name, "{SHA1}%s" % d
else:
return name, value
def log_curl_request(self, method, url, kwargs):
curl = ['curl -i -X %s' % method]
for (key, value) in kwargs['headers'].items():
header = '-H \'%s: %s\'' % self.safe_header(key, value)
curl.append(header)
conn_params_fmt = [
('key_file', '--key %s'),
('cert_file', '--cert %s'),
('cacert', '--cacert %s'),
]
for (key, fmt) in conn_params_fmt:
value = self.connection_params[2].get(key)
if value:
curl.append(fmt % value)
if self.connection_params[2].get('insecure'):
curl.append('-k')
if 'body' in kwargs:
curl.append('-d \'%s\'' % kwargs['body'])
curl.append('%s/%s' % (self.endpoint.rstrip('/'), url.lstrip('/')))
LOG.debug(' '.join(curl))
@staticmethod
def log_http_response(resp, body=None):
status = (resp.version / 10.0, resp.status, resp.reason)
dump = ['\nHTTP/%.1f %s %s' % status]
dump.extend(['%s: %s' % (k, v) for k, v in resp.getheaders()])
dump.append('')
if body:
dump.extend([body, ''])
LOG.debug('\n'.join(dump))
def _make_connection_url(self, url):
(_class, _args, _kwargs) = self.connection_params
base_url = _args[2]
return '%s/%s' % (base_url.rstrip('/'), url.lstrip('/'))
def _http_request(self, url, method, **kwargs):
"""Send an http request with the specified characteristics.
Wrapper around httplib.HTTP(S)Connection.request to handle tasks such
as setting headers and error handling.
"""
# Copy the kwargs so we can reuse the original in case of redirects
kwargs['headers'] = copy.deepcopy(kwargs.get('headers', {}))
kwargs['headers'].setdefault('User-Agent', USER_AGENT)
auth_token = self.auth_token()
if auth_token:
kwargs['headers'].setdefault('X-Auth-Token', auth_token)
self.log_curl_request(method, url, kwargs)
conn = self.get_connection()
try:
if self.proxy_url:
conn_url = (self.endpoint.rstrip('/') +
self._make_connection_url(url))
else:
conn_url = self._make_connection_url(url)
conn.request(method, conn_url, **kwargs)
resp = conn.getresponse()
except socket.gaierror as e:
message = ("Error finding address for %(url)s: %(e)s"
% dict(url=url, e=e))
raise exc.InvalidEndpoint(message=message)
except (socket.error, socket.timeout) as e:
endpoint = self.endpoint
message = ("Error communicating with %(endpoint)s %(e)s"
% dict(endpoint=endpoint, e=e))
raise exc.CommunicationError(message=message)
body_iter = ResponseBodyIterator(resp)
# Read body into string if it isn't obviously image data
if resp.getheader('content-type', None) != 'application/octet-stream':
body_str = ''.join([chunk for chunk in body_iter])
self.log_http_response(resp, body_str)
body_iter = six.StringIO(body_str)
else:
self.log_http_response(resp)
if 400 <= resp.status < 600:
LOG.warn("Request returned failure status.")
raise exc.from_response(resp, ''.join(body_iter))
elif resp.status in (301, 302, 305):
# Redirected. Reissue the request to the new location.
return self._http_request(resp['location'], method, **kwargs)
elif resp.status == 300:
raise exc.from_response(resp)
return resp, body_iter
def json_request(self, method, url, **kwargs):
kwargs.setdefault('headers', {})
kwargs['headers'].setdefault('Content-Type', 'application/json')
kwargs['headers'].setdefault('Accept', 'application/json')
if 'body' in kwargs:
kwargs['body'] = json.dumps(kwargs['body'])
resp, body_iter = self._http_request(url, method, **kwargs)
content_type = resp.getheader('content-type', None)
if resp.status == 204 or resp.status == 205 or content_type is None:
return resp, list()
if 'application/json' in content_type:
body = ''.join([chunk for chunk in body_iter])
try:
body = json.loads(body)
except ValueError:
LOG.error('Could not decode response body as JSON')
else:
body = None
return resp, body
def raw_request(self, method, url, **kwargs):
kwargs.setdefault('headers', {})
kwargs['headers'].setdefault('Content-Type',
'application/octet-stream')
return self._http_request(url, method, **kwargs)
def get_proxy_url(self):
scheme = urllib.parse.urlparse(self.endpoint).scheme
if scheme == 'https':
return os.environ.get('https_proxy')
elif scheme == 'http':
return os.environ.get('http_proxy')
msg = 'Unsupported scheme: %s' % scheme
raise exc.InvalidEndpoint(msg)
class VerifiedHTTPSConnection(httplib.HTTPSConnection):
"""httplib-compatibile connection using client-side SSL authentication
:see http://code.activestate.com/recipes/
577548-https-httplib-client-connection-with-certificate-v/
"""
def __init__(self, host, port, key_file=None, cert_file=None,
cacert=None, timeout=None, insecure=False):
httplib.HTTPSConnection.__init__(self, host, port, key_file=key_file,
cert_file=cert_file)
self.key_file = key_file
self.cert_file = cert_file
if cacert is not None:
self.cacert = cacert
else:
self.cacert = self.get_system_ca_file()
self.timeout = timeout
self.insecure = insecure
def connect(self):
"""Connect to a host on a given (SSL) port.
If cacert is pointing somewhere, use it to check Server Certificate.
Redefined/copied and extended from httplib.py:1105 (Python 2.6.x).
This is needed to pass cert_reqs=ssl.CERT_REQUIRED as parameter to
ssl.wrap_socket(), which forces SSL to check server certificate against
our client certificate.
"""
sock = socket.create_connection((self.host, self.port), self.timeout)
if self._tunnel_host:
self.sock = sock
self._tunnel()
if self.insecure is True:
kwargs = {'cert_reqs': ssl.CERT_NONE}
else:
kwargs = {'cert_reqs': ssl.CERT_REQUIRED, 'ca_certs': self.cacert}
if self.cert_file:
kwargs['certfile'] = self.cert_file
if self.key_file:
kwargs['keyfile'] = self.key_file
self.sock = ssl.wrap_socket(sock, **kwargs)
@staticmethod
def get_system_ca_file():
"""Return path to system default CA file."""
# Standard CA file locations for Debian/Ubuntu, RedHat/Fedora,
# Suse, FreeBSD/OpenBSD
ca_path = ['/etc/ssl/certs/ca-certificates.crt',
'/etc/pki/tls/certs/ca-bundle.crt',
'/etc/ssl/ca-bundle.pem',
'/etc/ssl/cert.pem']
for ca in ca_path:
if os.path.exists(ca):
return ca
return None
class ResponseBodyIterator(object):
"""A class that acts as an iterator over an HTTP response."""
def __init__(self, resp):
self.resp = resp
def __iter__(self):
while True:
yield self.next()
def next(self):
chunk = self.resp.read(CHUNKSIZE)
if chunk:
return chunk
else:
raise StopIteration()