Source code for ucsschool.kelvin.client.base

# -*- coding: utf-8 -*-
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import copy
import logging
from abc import ABC
from typing import Any, AsyncIterator, Dict, Iterable, List, TypeVar
from urllib.parse import unquote

from .exceptions import InvalidRequest, NoObject
from .session import Session

KelvinObjectType = TypeVar("KelvinObjectType", bound="KelvinObject")

logger = logging.getLogger(__name__)


[docs]class KelvinObject(ABC): _class_display_name = "Kelvin Object" _kelvin_attrs = ["name", "ucsschool_roles", "udm_properties"] def __init__( self, *, name: str = None, ucsschool_roles: List[str] = None, udm_properties: Dict[str, Any] = None, dn: str = None, url: str = None, session: Session = None, language: str = None, **kwargs, ): self.name = name self.ucsschool_roles = ucsschool_roles self.udm_properties = udm_properties or {} self.dn = dn self.url = url self.session = session if language: self.session.language = language self._resource_class = KelvinResource self._fresh = True self._deleted = False self._old_attrs = {} self._update_old_attrs() def __repr__(self): req_attrs_vals = [f"{attr!r}={value!r}" for attr, value in self._required_get_attrs.items()] if hasattr(self, "dn") and self.dn: req_attrs_vals.append(f"dn={self.dn!r}") return f"{self.__class__.__name__}({', '.join(req_attrs_vals)})"
[docs] async def reload(self) -> KelvinObjectType: """ Reload properties of object from the Kelvin API. :raises ucsschool.kelvin.client.NoObject: if the object cannot be found :return: self """ if self._deleted: logger.warning( "[%s] %s %s has been deleted! Trying to load it anyway...", self.session.request_id[:10], self._class_display_name, self, ) obj = await self._resource_class(session=self.session).get(**self._required_get_attrs) for k, v in obj.as_dict().items(): setattr(self, k, v) self._update_old_attrs() self._fresh = True return self
[docs] async def save(self) -> KelvinObjectType: if self._deleted: raise RuntimeError(f"{self} has been deleted.") if not all(self._required_save_attrs.values()): raise AssertionError( f"{self.__class__.__name__}.save() requires attribute(s) to be set: " f"{', '.join(self._resource_class.Meta.required_save_attrs)}." ) if not self._fresh: logger.debug( "[%s] Saving possibly stale Kelvin object instance.", self.session.request_id[:10] ) data = self._to_kelvin_request_data() # assumption: if self.url was set, the object exists in the Kelvin API # so if it's not set, we'll try to create the object if not self.url: resp_json = await self.session.post( url=self._resource_class(session=self.session).collection_url, json=data ) resp_obj = self._from_kelvin_response(resp_json) for k, v in resp_obj.as_dict().items(): setattr(self, k, v) self._fresh = False return self # self.url was set -> modify object # TODO: or creation failed and this is the fall-back resp_json = await self.session.put(url=self.url, json=data) resp_obj = self._from_kelvin_response(resp_json) for k, v in resp_obj.as_dict().items(): setattr(self, k, v) self._fresh = False return self
[docs] async def delete(self) -> None: if self._deleted: logger.warning("[%s] %s has already been deleted.", self.session.request_id[:10], self) return if not self.url: raise RuntimeError("Attribute 'url' unset. Run 'reload()' before 'delete()'.") await self.session.delete(self.url) self._deleted = True
[docs] def as_dict(self) -> Dict[str, Any]: attrs = self._kelvin_attrs + ["dn", "url"] _dict_repr = copy.deepcopy(dict((attr, getattr(self, attr)) for attr in attrs)) return _dict_repr
@classmethod def _from_kelvin_response(cls, response: Dict[str, Any]) -> KelvinObjectType: try: # school url to school name school_url = response["school"] tmp = unquote(school_url.rsplit("/", 1)[-1]) response["school"] = tmp.split("?")[0] except (IndexError, KeyError): pass return cls(**response) def _to_kelvin_request_data(self) -> Dict[str, Any]: data = self.as_dict() if not data["ucsschool_roles"]: del data["ucsschool_roles"] del data["dn"] del data["url"] try: # school name to school url data["school"] = f"{self.session.urls['school']}{data['school']}" except KeyError: pass return data @property def _required_get_attrs(self) -> Dict[str, Any]: return dict((attr, getattr(self, attr)) for attr in self._resource_class.Meta.required_get_attrs) @property def _required_save_attrs(self) -> Dict[str, Any]: return dict( (attr, getattr(self, attr)) for attr in self._resource_class.Meta.required_save_attrs ) def _update_old_attrs(self): self._old_attrs.update(self._required_get_attrs)
[docs]class KelvinResource(ABC):
[docs] class Meta: kelvin_object: KelvinObjectType = KelvinObject required_get_attrs: Iterable[str] = ("name",) required_head_attrs: Iterable[str] = ("name",) required_search_attrs: Iterable[str] = ("school",)
def __init__(self, session: Session, language: str = None): self.session = session if language: self.session.language = language self.collection_url = "" self.object_url = ""
[docs] async def get(self, **kwargs) -> KelvinObjectType: if not all(attr in kwargs for attr in self.Meta.required_get_attrs): raise AssertionError( f"{self.__class__.__name__}.get() requires argument(s): " f"{', '.join(self.Meta.required_get_attrs)}." ) url = self.object_url.format(**kwargs) try: return await self.get_from_url(url) except NoObject as exc: raise NoObject( f"{self.Meta.kelvin_object._class_display_name} not found at URL {url!r} using " f"attributes {kwargs!r}.", reason=exc.reason, status=exc.status, url=url, ) from exc
[docs] async def exists(self, **kwargs) -> bool: if not all(attr in kwargs for attr in self.Meta.required_head_attrs): raise AssertionError( f"{self.__class__.__name__}.get() requires argument(s): " f"{', '.join(self.Meta.required_get_attrs)}." ) url = self.object_url.format(**kwargs) status_code: int = await self.session.head(url) if status_code == 200: return True if status_code == 404: return False logger.warning( "There was a problem with HEAD for %s. Trying with GET instead. Status code: %s", url, status_code, ) try: await self.get(**kwargs) except NoObject: return False return True
[docs] async def get_from_url(self, url: str) -> KelvinObjectType: resp_json: Dict[str, Any] = await self.session.get(url) obj = self.Meta.kelvin_object._from_kelvin_response(resp_json) obj.session = self.session return obj
[docs] async def search(self, **kwargs) -> AsyncIterator[KelvinObjectType]: self._check_search_attrs(**kwargs) # not necessary, but will simplify the query string for k in [k for k, v in kwargs.items() if v in ("", "*")]: del kwargs[k] resp_json: List[Dict[str, Any]] = await self.session.get(self.collection_url, params=kwargs) for resp in resp_json: obj = self.Meta.kelvin_object._from_kelvin_response(resp) obj.session = self.session yield obj
def _check_search_attrs(self, **kwargs) -> None: """ :raises ucsschool.kelvin.client.InvalidRequest: when there is a problem with the kwargs for `search()` """ if not all(attr in kwargs for attr in self.Meta.required_search_attrs): raise InvalidRequest( f"{self.__class__.__name__}.search() requires argument(s): " f"{', '.join(self.Meta.required_search_attrs)}." )