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Diffstat (limited to 'client/escalatorclient/openstack/common/apiclient/base.py')
| -rw-r--r-- | client/escalatorclient/openstack/common/apiclient/base.py | 532 |
1 files changed, 532 insertions, 0 deletions
diff --git a/client/escalatorclient/openstack/common/apiclient/base.py b/client/escalatorclient/openstack/common/apiclient/base.py new file mode 100644 index 0000000..eb7218b --- /dev/null +++ b/client/escalatorclient/openstack/common/apiclient/base.py @@ -0,0 +1,532 @@ +# Copyright 2010 Jacob Kaplan-Moss +# Copyright 2011 OpenStack Foundation +# Copyright 2012 Grid Dynamics +# Copyright 2013 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. + +""" +Base utilities to build API operation managers and objects on top of. +""" + +######################################################################## +# +# THIS MODULE IS DEPRECATED +# +# Please refer to +# https://etherpad.openstack.org/p/kilo-escalatorclient-library-proposals for +# the discussion leading to this deprecation. +# +# We recommend checking out the python-openstacksdk project +# (https://launchpad.net/python-openstacksdk) instead. +# +######################################################################## + + +# E1102: %s is not callable +# pylint: disable=E1102 + +import abc +import copy + +from oslo_utils import strutils +import six +from six.moves.urllib import parse + +from escalatorclient.openstack.common._i18n import _ +from escalatorclient.openstack.common.apiclient import exceptions + + +def getid(obj): + """Return id if argument is a Resource. + + Abstracts the common pattern of allowing both an object or an object's ID + (UUID) as a parameter when dealing with relationships. + """ + try: + if obj.uuid: + return obj.uuid + except AttributeError: + pass + try: + return obj.id + except AttributeError: + return obj + + +# TODO(aababilov): call run_hooks() in HookableMixin's child classes +class HookableMixin(object): + """Mixin so classes can register and run hooks.""" + _hooks_map = {} + + @classmethod + def add_hook(cls, hook_type, hook_func): + """Add a new hook of specified type. + + :param cls: class that registers hooks + :param hook_type: hook type, e.g., '__pre_parse_args__' + :param hook_func: hook function + """ + if hook_type not in cls._hooks_map: + cls._hooks_map[hook_type] = [] + + cls._hooks_map[hook_type].append(hook_func) + + @classmethod + def run_hooks(cls, hook_type, *args, **kwargs): + """Run all hooks of specified type. + + :param cls: class that registers hooks + :param hook_type: hook type, e.g., '__pre_parse_args__' + :param args: args to be passed to every hook function + :param kwargs: kwargs to be passed to every hook function + """ + hook_funcs = cls._hooks_map.get(hook_type) or [] + for hook_func in hook_funcs: + hook_func(*args, **kwargs) + + +class BaseManager(HookableMixin): + """Basic manager type providing common operations. + + Managers interact with a particular type of API (servers, flavors, images, + etc.) and provide CRUD operations for them. + """ + resource_class = None + + def __init__(self, client): + """Initializes BaseManager with `client`. + + :param client: instance of BaseClient descendant for HTTP requests + """ + super(BaseManager, self).__init__() + self.client = client + + def _list(self, url, response_key=None, obj_class=None, json=None): + """List the collection. + + :param url: a partial URL, e.g., '/servers' + :param response_key: the key to be looked up in response dictionary, + e.g., 'servers'. If response_key is None - all response body + will be used. + :param obj_class: class for constructing the returned objects + (self.resource_class will be used by default) + :param json: data that will be encoded as JSON and passed in POST + request (GET will be sent by default) + """ + if json: + body = self.client.post(url, json=json).json() + else: + body = self.client.get(url).json() + + if obj_class is None: + obj_class = self.resource_class + + data = body[response_key] if response_key is not None else body + # NOTE(ja): keystone returns values as list as {'values': [ ... ]} + # unlike other services which just return the list... + try: + data = data['values'] + except (KeyError, TypeError): + pass + + return [obj_class(self, res, loaded=True) for res in data if res] + + def _get(self, url, response_key=None): + """Get an object from collection. + + :param url: a partial URL, e.g., '/servers' + :param response_key: the key to be looked up in response dictionary, + e.g., 'server'. If response_key is None - all response body + will be used. + """ + body = self.client.get(url).json() + data = body[response_key] if response_key is not None else body + return self.resource_class(self, data, loaded=True) + + def _head(self, url): + """Retrieve request headers for an object. + + :param url: a partial URL, e.g., '/servers' + """ + resp = self.client.head(url) + return resp.status_code == 204 + + def _post(self, url, json, response_key=None, return_raw=False): + """Create an object. + + :param url: a partial URL, e.g., '/servers' + :param json: data that will be encoded as JSON and passed in POST + request (GET will be sent by default) + :param response_key: the key to be looked up in response dictionary, + e.g., 'server'. If response_key is None - all response body + will be used. + :param return_raw: flag to force returning raw JSON instead of + Python object of self.resource_class + """ + body = self.client.post(url, json=json).json() + data = body[response_key] if response_key is not None else body + if return_raw: + return data + return self.resource_class(self, data) + + def _put(self, url, json=None, response_key=None): + """Update an object with PUT method. + + :param url: a partial URL, e.g., '/servers' + :param json: data that will be encoded as JSON and passed in POST + request (GET will be sent by default) + :param response_key: the key to be looked up in response dictionary, + e.g., 'servers'. If response_key is None - all response body + will be used. + """ + resp = self.client.put(url, json=json) + # PUT requests may not return a body + if resp.content: + body = resp.json() + if response_key is not None: + return self.resource_class(self, body[response_key]) + else: + return self.resource_class(self, body) + + def _patch(self, url, json=None, response_key=None): + """Update an object with PATCH method. + + :param url: a partial URL, e.g., '/servers' + :param json: data that will be encoded as JSON and passed in POST + request (GET will be sent by default) + :param response_key: the key to be looked up in response dictionary, + e.g., 'servers'. If response_key is None - all response body + will be used. + """ + body = self.client.patch(url, json=json).json() + if response_key is not None: + return self.resource_class(self, body[response_key]) + else: + return self.resource_class(self, body) + + def _delete(self, url): + """Delete an object. + + :param url: a partial URL, e.g., '/servers/my-server' + """ + return self.client.delete(url) + + +@six.add_metaclass(abc.ABCMeta) +class ManagerWithFind(BaseManager): + """Manager with additional `find()`/`findall()` methods.""" + + @abc.abstractmethod + def list(self): + pass + + def find(self, **kwargs): + """Find a single item with attributes matching ``**kwargs``. + + This isn't very efficient: it loads the entire list then filters on + the Python side. + """ + matches = self.findall(**kwargs) + num_matches = len(matches) + if num_matches == 0: + msg = _("No %(name)s matching %(args)s.") % { + 'name': self.resource_class.__name__, + 'args': kwargs + } + raise exceptions.NotFound(msg) + elif num_matches > 1: + raise exceptions.NoUniqueMatch() + else: + return matches[0] + + def findall(self, **kwargs): + """Find all items with attributes matching ``**kwargs``. + + This isn't very efficient: it loads the entire list then filters on + the Python side. + """ + found = [] + searches = kwargs.items() + + for obj in self.list(): + try: + if all(getattr(obj, attr) == value + for (attr, value) in searches): + found.append(obj) + except AttributeError: + continue + + return found + + +class CrudManager(BaseManager): + """Base manager class for manipulating entities. + + Children of this class are expected to define a `collection_key` and `key`. + + - `collection_key`: Usually a plural noun by convention (e.g. `entities`); + used to refer collections in both URL's (e.g. `/v3/entities`) and JSON + objects containing a list of member resources (e.g. `{'entities': [{}, + {}, {}]}`). + - `key`: Usually a singular noun by convention (e.g. `entity`); used to + refer to an individual member of the collection. + + """ + collection_key = None + key = None + + def build_url(self, base_url=None, **kwargs): + """Builds a resource URL for the given kwargs. + + Given an example collection where `collection_key = 'entities'` and + `key = 'entity'`, the following URL's could be generated. + + By default, the URL will represent a collection of entities, e.g.:: + + /entities + + If kwargs contains an `entity_id`, then the URL will represent a + specific member, e.g.:: + + /entities/{entity_id} + + :param base_url: if provided, the generated URL will be appended to it + """ + url = base_url if base_url is not None else '' + + url += '/%s' % self.collection_key + + # do we have a specific entity? + entity_id = kwargs.get('%s_id' % self.key) + if entity_id is not None: + url += '/%s' % entity_id + + return url + + def _filter_kwargs(self, kwargs): + """Drop null values and handle ids.""" + for key, ref in six.iteritems(kwargs.copy()): + if ref is None: + kwargs.pop(key) + else: + if isinstance(ref, Resource): + kwargs.pop(key) + kwargs['%s_id' % key] = getid(ref) + return kwargs + + def create(self, **kwargs): + kwargs = self._filter_kwargs(kwargs) + return self._post( + self.build_url(**kwargs), + {self.key: kwargs}, + self.key) + + def get(self, **kwargs): + kwargs = self._filter_kwargs(kwargs) + return self._get( + self.build_url(**kwargs), + self.key) + + def head(self, **kwargs): + kwargs = self._filter_kwargs(kwargs) + return self._head(self.build_url(**kwargs)) + + def list(self, base_url=None, **kwargs): + """List the collection. + + :param base_url: if provided, the generated URL will be appended to it + """ + kwargs = self._filter_kwargs(kwargs) + + return self._list( + '%(base_url)s%(query)s' % { + 'base_url': self.build_url(base_url=base_url, **kwargs), + 'query': '?%s' % parse.urlencode(kwargs) if kwargs else '', + }, + self.collection_key) + + def put(self, base_url=None, **kwargs): + """Update an element. + + :param base_url: if provided, the generated URL will be appended to it + """ + kwargs = self._filter_kwargs(kwargs) + + return self._put(self.build_url(base_url=base_url, **kwargs)) + + def update(self, **kwargs): + kwargs = self._filter_kwargs(kwargs) + params = kwargs.copy() + params.pop('%s_id' % self.key) + + return self._patch( + self.build_url(**kwargs), + {self.key: params}, + self.key) + + def delete(self, **kwargs): + kwargs = self._filter_kwargs(kwargs) + + return self._delete( + self.build_url(**kwargs)) + + def find(self, base_url=None, **kwargs): + """Find a single item with attributes matching ``**kwargs``. + + :param base_url: if provided, the generated URL will be appended to it + """ + kwargs = self._filter_kwargs(kwargs) + + rl = self._list( + '%(base_url)s%(query)s' % { + 'base_url': self.build_url(base_url=base_url, **kwargs), + 'query': '?%s' % parse.urlencode(kwargs) if kwargs else '', + }, + self.collection_key) + num = len(rl) + + if num == 0: + msg = _("No %(name)s matching %(args)s.") % { + 'name': self.resource_class.__name__, + 'args': kwargs + } + raise exceptions.NotFound(404, msg) + elif num > 1: + raise exceptions.NoUniqueMatch + else: + return rl[0] + + +class Extension(HookableMixin): + """Extension descriptor.""" + + SUPPORTED_HOOKS = ('__pre_parse_args__', '__post_parse_args__') + manager_class = None + + def __init__(self, name, module): + super(Extension, self).__init__() + self.name = name + self.module = module + self._parse_extension_module() + + def _parse_extension_module(self): + self.manager_class = None + for attr_name, attr_value in self.module.__dict__.items(): + if attr_name in self.SUPPORTED_HOOKS: + self.add_hook(attr_name, attr_value) + else: + try: + if issubclass(attr_value, BaseManager): + self.manager_class = attr_value + except TypeError: + pass + + def __repr__(self): + return "<Extension '%s'>" % self.name + + +class Resource(object): + """Base class for OpenStack resources (tenant, user, etc.). + + This is pretty much just a bag for attributes. + """ + + HUMAN_ID = False + NAME_ATTR = 'name' + + def __init__(self, manager, info, loaded=False): + """Populate and bind to a manager. + + :param manager: BaseManager object + :param info: dictionary representing resource attributes + :param loaded: prevent lazy-loading if set to True + """ + self.manager = manager + self._info = info + self._add_details(info) + self._loaded = loaded + + def __repr__(self): + reprkeys = sorted(k + for k in self.__dict__.keys() + if k[0] != '_' and k != 'manager') + info = ", ".join("%s=%s" % (k, getattr(self, k)) for k in reprkeys) + return "<%s %s>" % (self.__class__.__name__, info) + + @property + def human_id(self): + """Human-readable ID which can be used for bash completion. + """ + if self.HUMAN_ID: + name = getattr(self, self.NAME_ATTR, None) + if name is not None: + return strutils.to_slug(name) + return None + + def _add_details(self, info): + for (k, v) in six.iteritems(info): + try: + setattr(self, k, v) + self._info[k] = v + except AttributeError: + # In this case we already defined the attribute on the class + pass + + def __getattr__(self, k): + if k not in self.__dict__: + # NOTE(bcwaldon): disallow lazy-loading if already loaded once + if not self.is_loaded(): + self.get() + return self.__getattr__(k) + + raise AttributeError(k) + else: + return self.__dict__[k] + + def get(self): + """Support for lazy loading details. + + Some clients, such as novaclient have the option to lazy load the + details, details which can be loaded with this function. + """ + # set_loaded() first ... so if we have to bail, we know we tried. + self.set_loaded(True) + if not hasattr(self.manager, 'get'): + return + + new = self.manager.get(self.id) + if new: + self._add_details(new._info) + self._add_details( + {'x_request_id': self.manager.client.last_request_id}) + + def __eq__(self, other): + if not isinstance(other, Resource): + return NotImplemented + # two resources of different types are not equal + if not isinstance(other, self.__class__): + return False + if hasattr(self, 'id') and hasattr(other, 'id'): + return self.id == other.id + return self._info == other._info + + def is_loaded(self): + return self._loaded + + def set_loaded(self, val): + self._loaded = val + + def to_dict(self): + return copy.deepcopy(self._info) |