Synnefo » ./kamaki

# Copyright 2011-2012 GRNET S.A. All rights reserved.

#

# Redistribution and use in source and binary forms, with or

# without modification, are permitted provided that the following

# conditions are met:

#

#   1. Redistributions of source code must retain the above

#      copyright notice, self.list of conditions and the following

#      disclaimer.

#

#   2. Redistributions in binary form must reproduce the above

#      copyright notice, self.list of conditions and the following

#      disclaimer in the documentation and/or other materials

#      provided with the distribution.

#

# THIS SOFTWARE IS PROVIDED BY GRNET S.A. ``AS IS'' AND ANY EXPRESS

# OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL GRNET S.A OR

# CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

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# USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED

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# documentation are those of the authors and should not be

# interpreted as representing official policies, either expressed

# or implied, of GRNET S.A.

from threading import Thread

from json import dumps, loads

from time import time

import logging

from kamaki.clients.connection.kamakicon import KamakiHTTPConnection

from kamaki.clients.connection.errors import HTTPConnectionError

from kamaki.clients.connection.errors import HTTPResponseError

sendlog = logging.getLogger('clients.send')

datasendlog = logging.getLogger('data.send')

recvlog = logging.getLogger('clients.recv')

datarecvlog = logging.getLogger('data.recv')

class ClientError(Exception):

    def __init__(self, message, status=0, details=None):

        try:

            message += '' if message and message[-1] == '\n' else '\n'

            serv_stat, sep, new_msg = message.partition('{')

            new_msg = sep + new_msg

            json_msg = loads(new_msg)

            key = json_msg.keys()[0]

            json_msg = json_msg[key]

            message = '%s %s (%s)\n' % (serv_stat, key, json_msg['message'])\

                if 'message' in json_msg else '%s %s' % (serv_stat, key)

            if 'code' in json_msg:

                status = json_msg['code']

            if 'details' in json_msg:

                if not details:

                    details = []

                elif not isinstance(details, list):

                    details = [details]

                if json_msg['details']:

                    details.append(json_msg['details'])

        except:

            pass

        super(ClientError, self).__init__(message)

        self.status = status

        self.details = details if details else []

class SilentEvent(Thread):

    """ Thread-run method(*args, **kwargs)

        put exception in exception_bucket

    """

    def __init__(self, method, *args, **kwargs):

        super(self.__class__, self).__init__()

        self.method = method

        self.args = args

        self.kwargs = kwargs

    @property

    def exception(self):

        return getattr(self, '_exception', False)

    @property

    def value(self):

        return getattr(self, '_value', None)

    def run(self):

        try:

            self._value = self.method(*(self.args), **(self.kwargs))

        except Exception as e:

            recvlog.debug('Thread %s got exception %s\n<%s %s' % (

                self,

                type(e),

                e.status if isinstance(e, ClientError) else '',

                e))

            self._exception = e

class Client(object):

    POOL_SIZE = 7

    def __init__(self, base_url, token, http_client=KamakiHTTPConnection()):

        self.base_url = base_url

        self.token = token

        self.headers = {}

        self.DATE_FORMATS = ["%a %b %d %H:%M:%S %Y",

            "%A, %d-%b-%y %H:%M:%S GMT",

            "%a, %d %b %Y %H:%M:%S GMT"]

        self.http_client = http_client

    def _init_thread_limit(self, limit=1):

        self._thread_limit = limit

        self._elapsed_old = 0.0

        self._elapsed_new = 0.0

    def _watch_thread_limit(self, threadlist):

        recvlog.debug('# running threads: %s' % len(threadlist))

        if self._elapsed_old > self._elapsed_new\

        and self._thread_limit < self.POOL_SIZE:

            self._thread_limit += 1

        elif self._elapsed_old < self._elapsed_new and self._thread_limit > 1:

            self._thread_limit -= 1

        self._elapsed_old = self._elapsed_new

        if len(threadlist) >= self._thread_limit:

            self._elapsed_new = 0.0

            for thread in threadlist:

                begin_time = time()

                thread.join()

                self._elapsed_new += time() - begin_time

            self._elapsed_new = self._elapsed_new / len(threadlist)

            return []

        return threadlist

    def _raise_for_status(self, r):

        status_msg = getattr(r, 'status', '')

        try:

            message = '%s %s\n' % (status_msg, r.text)

        except:

            message = '%s %s\n' % (status_msg, r)

        status = getattr(r, 'status_code', getattr(r, 'status', 0))

        raise ClientError(message, status=status)

    def set_header(self, name, value, iff=True):

        """Set a header 'name':'value'"""

        if value is not None and iff:

            self.http_client.set_header(name, value)

    def set_param(self, name, value=None, iff=True):

        if iff:

            self.http_client.set_param(name, value)

    def set_default_header(self, name, value):

        self.http_client.headers.setdefault(name, value)

    def request(self,

        method,

        path,

        async_headers={},

        async_params={},

        **kwargs):

        """In threaded/asynchronous requests, headers and params are not safe

        Therefore, the standard self.set_header/param system can be used only

        for headers and params that are common for all requests. All other

        params and headers should passes as

        @param async_headers

        @async_params

        E.g. in most queries the 'X-Auth-Token' header might be the same for

        all, but the 'Range' header might be different from request to request.

        """

        try:

            success = kwargs.pop('success', 200)

            data = kwargs.pop('data', None)

            self.set_default_header('X-Auth-Token', self.token)

            if 'json' in kwargs:

                data = dumps(kwargs.pop('json'))

                self.set_default_header('Content-Type', 'application/json')

            if data:

                self.set_default_header('Content-Length', unicode(len(data)))

            sendlog.info('perform a %s @ %s', method, self.base_url)

            self.http_client.url = self.base_url

            self.http_client.path = path

            r = self.http_client.perform_request(method,

                data,

                async_headers,

                async_params)

            req = self.http_client

            sendlog.info('%s %s', method, req.url)

            headers = dict(req.headers)

            headers.update(async_headers)

            for key, val in headers.items():

                sendlog.info('\t%s: %s', key, val)

            sendlog.info('')

            if data:

                datasendlog.info(data)

            recvlog.info('%d %s', r.status_code, r.status)

            for key, val in r.headers.items():

                recvlog.info('%s: %s', key, val)

            if r.content:

                datarecvlog.info(r.content)

        except (HTTPResponseError, HTTPConnectionError) as err:

            from traceback import format_stack

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

            self.http_client.reset_headers()

            self.http_client.reset_params()

            errstr = '%s' % err

            if not errstr:

                errstr = ('%s' % type(err))[7:-2]

            raise ClientError('%s\n' % errstr,

                status=getattr(err, 'status', 0) or getattr(err, 'errno', 0))

        self.http_client.reset_headers()

        self.http_client.reset_params()

        if success is not None:

            # Success can either be an in or a collection

            success = (success,) if isinstance(success, int) else success

            if r.status_code not in success:

                r.release()

                self._raise_for_status(r)

        return r

    def delete(self, path, **kwargs):

        return self.request('delete', path, **kwargs)

    def get(self, path, **kwargs):

        return self.request('get', path, **kwargs)

    def head(self, path, **kwargs):

        return self.request('head', path, **kwargs)

    def post(self, path, **kwargs):

        return self.request('post', path, **kwargs)

    def put(self, path, **kwargs):

        return self.request('put', path, **kwargs)

    def copy(self, path, **kwargs):

        return self.request('copy', path, **kwargs)

    def move(self, path, **kwargs):

        return self.request('move', path, **kwargs)