Synnefo » ./kamaki

# Copyright 2012 GRNET S.A. All rights reserved.

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from urlparse import urlparse

from objpool.http import get_http_connection

from kamaki.clients.connection import HTTPConnection, HTTPResponse

from kamaki.clients.connection.errors import HTTPConnectionError

from kamaki.clients.connection.errors import HTTPResponseError

from socket import gaierror

from json import loads

from time import sleep

from httplib import ResponseNotReady

class KamakiHTTPResponse(HTTPResponse):

    def _get_response(self):

        if self.prefetched:

            return

        ready = False

        while not ready:

            try:

                r = self.request.getresponse()

            except ResponseNotReady:

                sleep(0.001)

                continue

            break

        self.prefetched = True

        headers = {}

        for k, v in r.getheaders():

            headers.update({k: v})

        self.headers = headers

        self.content = r.read()

        self.status_code = r.status

        self.status = r.reason

        self.request.close()

    @property

    def text(self):

        """

        :returns: (str) content

        """

        self._get_response()

        return unicode(self._content)

    @text.setter

    def test(self, v):

        pass

    @property

    def json(self):

        """

        :returns: (dict) the json-formated content

        :raises HTTPResponseError: if content is not json formated

        """

        self._get_response()

        try:

            return loads(self._content)

        except ValueError as err:

            HTTPResponseError('Response not formated in JSON - %s' % err)

    @json.setter

    def json(self, v):

        pass

    def release(self):

        """ Release the connection. Should always be called if the response

        content hasn't been used.

        """

        if not self.prefetched:

            self.request.close()

class KamakiHTTPConnection(HTTPConnection):

    def _retrieve_connection_info(self, extra_params={}):

        """

        :param extra_params: (dict) key:val for url parameters

        :returns: (scheme, netloc, url?with&params)

        """

        if self.url:

            url = self.url if self.url[-1] == '/' else (self.url + '/')

        else:

            url = 'http://127.0.0.1'

        if self.path:

            url += self.path[1:] if self.path[0] == '/' else self.path

        params = dict(self.params)

        for k, v in extra_params.items():

            params[k] = v

        for i, (key, val) in enumerate(params.items()):

            param_str = ('?' if i == 0 else '&') + unicode(key)

            if val is not None:

                param_str += '=' + unicode(val)

            url += param_str

        parsed = urlparse(url)

        self.url = url

        self.path = parsed.path if parsed.path else '/'

        self.path += '?%s' % parsed.query if parsed.query else ''

        return (parsed.scheme, parsed.netloc)

    def perform_request(self,

        method=None,

        data=None,

        async_headers={},

        async_params={}):

        """

        :param method: (str) http method ('get', 'post', etc.)

        :param data: (binary object)

        :param async_headers: (dict) key:val headers that are used only for one

            request instance as opposed to self.headers, which remain to be

            used by following or parallel requests

        :param async_params: (dict) key:val url parameters that are used only

            for one request instance as opposed to self.params, which remain to

            be used by following or parallel requests

        :returns: (KamakiHTTPResponse) a response object

        :raises HTTPConnectionError: Connection failures

        """

        (scheme, netloc) = self._retrieve_connection_info(

            extra_params=async_params)

        headers = dict(self.headers)

        for k, v in async_headers.items():

            headers[k] = v

        #de-unicode headers to prepare them for http

        http_headers = {}

        for k, v in headers.items():

            http_headers[str(k)] = str(v)

        #get connection from pool

        conn = get_http_connection(netloc=netloc, scheme=scheme)

        try:

            #Be carefull, all non-body variables should not be unicode

            conn.request(method=str(method.upper()),

                url=str(self.path),

                headers=http_headers,

                body=data)

        except Exception as err:

            from traceback import format_stack

            from kamaki.clients import recvlog

            recvlog.debug('\n'.join(['%s' % type(err)] + format_stack()))

            conn.close()

            if isinstance(err, gaierror):

                raise HTTPConnectionError(

                    'Cannot connect to %s - %s' % (self.url, err))

            raise

        return KamakiHTTPResponse(conn)