Synnefo » ./kamaki

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

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from urlparse import urlparse

from urllib2 import quote

from objpool.http import get_http_connection

from traceback import format_stack

from kamaki.clients.connection import KamakiConnection, KamakiResponse

from kamaki.clients.connection.errors import KamakiConnectionError

from kamaki.clients.connection.errors import KamakiResponseError

from json import loads

from time import sleep

from httplib import ResponseNotReady

def _encode(v):

    if v and isinstance(v, unicode):

        return quote(v.encode('utf-8'))

    return v

class KamakiHTTPResponse(KamakiResponse):

    def _get_response(self):

        if self.prefetched:

            return

        try:

            while True:

                try:

                    r = self.request.getresponse()

                except ResponseNotReady:

                    sleep(0.001)

                else:

                    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

        finally:

            try:

                self.request.close()

            except Exception as err:

                from kamaki.clients import recvlog

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

                raise

    @property

    def text(self):

        """

        :returns: (str) content

        """

        self._get_response()

        return '%s' % self._content

    @text.setter

    def text(self, v):

        pass

    @property

    def json(self):

        """

        :returns: (dict) the json-formated content

        :raises KamakiResponseError: if content is not json formated

        """

        self._get_response()

        try:

            return loads(self._content)

        except ValueError as err:

            KamakiResponseError('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:

            try:

                self.request.close()

            except Exception as err:

                from kamaki.clients import recvlog

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

                raise

class KamakiHTTPConnection(KamakiConnection):

    def _retrieve_connection_info(self, extra_params={}):

        """ Set self.url to scheme://netloc/?params

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

        :returns: (scheme, netloc)

        """

        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)

        params.update(extra_params)

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

            val = _encode(val)

            url += '%s%s' % ('&' if i else '?', key)

            if val:

                url += '=%s' % val

        parsed = urlparse(url)

        self.url = url

        self.path = parsed.path or '/'

        if parsed.query:

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

        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 KamakiConnectionError: Connection failures

        """

        (scheme, netloc) = self._retrieve_connection_info(async_params)

        headers = dict(self.headers)

        for k, v in async_headers.items():

            v = _encode(v)

            headers[k] = v

        #de-unicode headers to prepare them for http

        http_headers = {}

        for k, v in headers.items():

            v = _encode(v)

            http_headers[k] = v

        #get connection from pool

        try:

            conn = get_http_connection(

                netloc=netloc,

                scheme=scheme,

                pool_size=self.poolsize)

        except ValueError as ve:

            raise KamakiConnectionError(

                'Cannot establish connection to %s %s' % (self.url, ve),

                errno=-1)

        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 IOError as ioe:

            raise KamakiConnectionError(

                'Cannot connect to %s: %s' % (self.url, ioe.strerror),

                errno=ioe.errno)

        except Exception as err:

            from kamaki.clients import recvlog

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

            conn.close()

            raise

        return KamakiHTTPResponse(conn)