python-heatclient/heatclient/common/http.py

# 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 logging
import os
import socket

import requests

from heatclient import exc
from heatclient.openstack.common import jsonutils
from heatclient.openstack.common.py3kcompat import urlutils

LOG = logging.getLogger(__name__)
if not LOG.handlers:
    LOG.addHandler(logging.StreamHandler())
USER_AGENT = 'python-heatclient'
CHUNKSIZE = 1024 * 64  # 64kB


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 HTTPClient(object):

    def __init__(self, endpoint, **kwargs):
        self.endpoint = endpoint
        self.auth_url = kwargs.get('auth_url')
        self.auth_token = kwargs.get('token')
        self.username = kwargs.get('username')
        self.password = kwargs.get('password')
        self.region_name = kwargs.get('region_name')
        self.include_pass = kwargs.get('include_pass')
        self.endpoint_url = endpoint

        self.cert_file = kwargs.get('cert_file')
        self.key_file = kwargs.get('key_file')

        self.ssl_connection_params = {
            'ca_file': kwargs.get('ca_file'),
            'cert_file': kwargs.get('cert_file'),
            'key_file': kwargs.get('key_file'),
            'insecure': kwargs.get('insecure'),
        }

        self.verify_cert = None
        if urlutils.urlparse(endpoint).scheme == "https":
            if kwargs.get('insecure'):
                self.verify_cert = False
            else:
                self.verify_cert = kwargs.get('ca_file', get_system_ca_file())

    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\'' % (key, value)
            curl.append(header)

        conn_params_fmt = [
            ('key_file', '--key %s'),
            ('cert_file', '--cert %s'),
            ('ca_file', '--cacert %s'),
        ]
        for (key, fmt) in conn_params_fmt:
            value = self.ssl_connection_params.get(key)
            if value:
                curl.append(fmt % value)

        if self.ssl_connection_params.get('insecure'):
            curl.append('-k')

        if 'data' in kwargs:
            curl.append('-d \'%s\'' % kwargs['data'])

        curl.append('%s%s' % (self.endpoint, url))
        LOG.debug(' '.join(curl))

    @staticmethod
    def log_http_response(resp):
        status = (resp.raw.version / 10.0, resp.status_code, resp.reason)
        dump = ['\nHTTP/%.1f %s %s' % status]
        dump.extend(['%s: %s' % (k, v) for k, v in resp.headers.items()])
        dump.append('')
        if resp.content:
            dump.extend([resp.content.decode(), ''])
        LOG.debug('\n'.join(dump))

    def _http_request(self, url, method, **kwargs):
        """Send an http request with the specified characteristics.

        Wrapper around requests.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)
        if self.auth_token:
            kwargs['headers'].setdefault('X-Auth-Token', self.auth_token)
        else:
            kwargs['headers'].update(self.credentials_headers())
        if self.auth_url:
            kwargs['headers'].setdefault('X-Auth-Url', self.auth_url)
        if self.region_name:
            kwargs['headers'].setdefault('X-Region-Name', self.region_name)
        if self.include_pass and not 'X-Auth-Key' in kwargs['headers']:
            kwargs['headers'].update(self.credentials_headers())

        self.log_curl_request(method, url, kwargs)

        if self.cert_file and self.key_file:
            kwargs['cert'] = (self.cert_file, self.key_file)

        if self.verify_cert is not None:
            kwargs['verify'] = self.verify_cert

        # We are not using requests builtin redirection on DELETE since it does
        # not follow the RFC having to resend the same method on a
        # redirect. For example if we do a DELETE on a URL and we get
        # a 302 RFC says that we should follow that URL with the same
        # method as before, requests doesn't follow that and send a
        # GET instead for the method.  See issue:
        # https://github.com/kennethreitz/requests/issues/1704
        # hopefully this could be fixed as they say in a comment in a
        # future point version i.e: 3.x
        if method == 'DELETE':
            allow_redirects = False
        else:
            allow_redirects = True

        try:
            resp = requests.request(
                method,
                self.endpoint_url + url,
                allow_redirects=allow_redirects,
                **kwargs)
        except socket.gaierror as e:
            message = ("Error finding address for %(url)s: %(e)s" %
                       {'url': self.endpoint_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" %
                       {'endpoint': endpoint, 'e': e})
            raise exc.CommunicationError(message=message)

        self.log_http_response(resp)

        if not 'X-Auth-Key' in kwargs['headers'] and \
                (resp.status_code == 401 or
                 (resp.status_code == 500 and "(HTTP 401)" in resp.content)):
            raise exc.HTTPUnauthorized("Authentication failed. Please try"
                                       " again with option "
                                       "--include-password or export "
                                       "HEAT_INCLUDE_PASSWORD=1\n%s"
                                       % resp.content)
        elif 400 <= resp.status_code < 600:
            raise exc.from_response(resp)
        elif resp.status_code in (301, 302, 305):
            # Redirected. Reissue the request to the new location.
            location = resp.headers.get('location')
            if location is None:
                message = "Location not returned with 302"
                raise exc.InvalidEndpoint(message=message)
            elif location.startswith(self.endpoint):
                # shave off the endpoint, it will be prepended when we recurse
                location = location[len(self.endpoint):]
            else:
                message = "Prohibited endpoint redirect %s" % location
                raise exc.InvalidEndpoint(message=message)
            return self._http_request(location, method, **kwargs)
        elif resp.status_code == 300:
            raise exc.from_response(resp)

        return resp

    def credentials_headers(self):
        creds = {}
        if self.username:
            creds['X-Auth-User'] = self.username
        if self.password:
            creds['X-Auth-Key'] = self.password
        return creds

    def json_request(self, method, url, **kwargs):
        kwargs.setdefault('headers', {})
        kwargs['headers'].setdefault('Content-Type', 'application/json')
        kwargs['headers'].setdefault('Accept', 'application/json')

        if 'data' in kwargs:
            kwargs['data'] = jsonutils.dumps(kwargs['data'])

        resp = self._http_request(url, method, **kwargs)
        body = resp.content
        if 'application/json' in resp.headers.get('content-type', ''):
            try:
                body = resp.json()
            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 client_request(self, method, url, **kwargs):
        resp, body = self.json_request(method, url, **kwargs)
        return resp

    def head(self, url, **kwargs):
        return self.client_request("HEAD", url, **kwargs)

    def get(self, url, **kwargs):
        return self.client_request("GET", url, **kwargs)

    def post(self, url, **kwargs):
        return self.client_request("POST", url, **kwargs)

    def put(self, url, **kwargs):
        return self.client_request("PUT", url, **kwargs)

    def delete(self, url, **kwargs):
        return self.raw_request("DELETE", url, **kwargs)

    def patch(self, url, **kwargs):
        return self.client_request("PATCH", url, **kwargs)