import abc
import math
import os
from typing import Any, List
from typing_extensions import Literal
from cowbird.permissions_synchronizer import Permission
from cowbird.typedefs import JSON, SettingsType
from cowbird.utils import get_logger, get_ssl_verify, get_timeout
[docs]
AnyHandlerParameter = Literal["priority", "url", "workspace_dir"]
[docs]
HANDLER_PRIORITY_PARAM: AnyHandlerParameter = "priority"
[docs]
HANDLER_URL_PARAM: AnyHandlerParameter = "url"
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HANDLER_WORKSPACE_DIR_PARAM: AnyHandlerParameter = "workspace_dir"
[docs]
HANDLER_PARAMETERS = frozenset([
HANDLER_PRIORITY_PARAM,
HANDLER_URL_PARAM,
HANDLER_WORKSPACE_DIR_PARAM
])
[docs]
LOGGER = get_logger(__name__)
[docs]
class HandlerConfigurationException(Exception):
"""
Exception thrown when a handler cannot be instantiated because of a bad configuration.
"""
[docs]
class Handler(abc.ABC):
[docs]
__slots__ = ["settings",
"name",
"ssl_verify",
"timeout",
HANDLER_PRIORITY_PARAM,
HANDLER_URL_PARAM,
HANDLER_WORKSPACE_DIR_PARAM
]
"""
Handler interface used to notify implemented handlers of users/permissions changes.
.. todo:: At some point we will need a consistency function that goes through all Magpie users and make sure that
handlers are up-to-date.
"""
@property
@abc.abstractmethod
[docs]
def required_params(self) -> List[AnyHandlerParameter]:
raise NotImplementedError
def __init__(self, settings: SettingsType, name: str, **kwargs: Any) -> None:
"""
:param settings: Cowbird settings for convenience
:param name: Handler name
:param kwargs: The base class handle, but doesn't require the following variables:
:param url: Location of the web service represented by the cowbird handler
:param workspace_dir: Workspace directory
:param priority: Relative priority between handlers while handling events.
Lower value has higher priority, default value is last.
"""
if getattr(self, "required_params", None) is None:
raise NotImplementedError("Handler 'required_params' must be overridden in inheriting class.")
[docs]
self.settings = settings
[docs]
self.priority = kwargs.get(HANDLER_PRIORITY_PARAM, math.inf)
[docs]
self.url = kwargs.get(HANDLER_URL_PARAM, None)
[docs]
self.workspace_dir = kwargs.get(HANDLER_WORKSPACE_DIR_PARAM, None)
# Handlers making outbound requests should use these settings to avoid SSLError on test/dev setup
[docs]
self.ssl_verify = get_ssl_verify(self.settings)
[docs]
self.timeout = get_timeout(self.settings)
for required_param in self.required_params: # pylint: disable=E1101,no-member
if required_param not in HANDLER_PARAMETERS:
raise HandlerConfigurationException(f"Invalid handler parameter : {required_param}")
if getattr(self, required_param) is None:
error_msg = f"{self.__class__.__name__} handler requires the following missing configuration " \
f"parameter : [{required_param}]"
LOGGER.error(error_msg)
raise HandlerConfigurationException(error_msg)
[docs]
def json(self) -> JSON:
return {"name": self.name}
[docs]
def _user_workspace_dir(self, user_name: str) -> str:
return os.path.join(self.workspace_dir, user_name)
@abc.abstractmethod
[docs]
def user_created(self, user_name: str) -> None:
raise NotImplementedError
@abc.abstractmethod
[docs]
def user_deleted(self, user_name: str) -> None:
raise NotImplementedError
@abc.abstractmethod
[docs]
def permission_created(self, permission: Permission) -> None:
raise NotImplementedError
@abc.abstractmethod
[docs]
def permission_deleted(self, permission: Permission) -> None:
raise NotImplementedError
@abc.abstractmethod
[docs]
def resync(self) -> None:
raise NotImplementedError