canaille-globuzma/canaille/backends/__init__.py

57 lines
1.4 KiB
Python

from contextlib import contextmanager
class Backend:
instance = None
def __init__(self, config):
Backend.instance = self
@classmethod
def get(cls):
return cls.instance
def init_app(self, app):
@app.before_request
def before_request():
return self.setup()
@app.after_request
def after_request(response):
self.teardown()
return response
@contextmanager
def session(self):
yield self.setup()
self.teardown()
@classmethod
def install(self):
"""
This methods prepares the database to host canaille data.
"""
raise NotImplementedError()
def setup(self):
"""
This method will be called before each http request,
it should open the connection to the backend.
"""
raise NotImplementedError()
def teardown(self):
"""
This method will be called after each http request,
it should close the connections to the backend.
"""
raise NotImplementedError()
@classmethod
def validate(cls, config):
"""
This method should validate the config part dedicated to the backend.
It should raise :class:`~canaille.configuration.ConfigurationError` when
errors are met.
"""
raise NotImplementedError()