canaille-globuzma/canaille/backends/models.py

93 lines
2.6 KiB
Python

class Model:
"""
Model abstract class.
"""
@classmethod
def query(cls, **kwargs):
"""
Performs a query on the database and return a collection of instances.
Parameters can be any valid attribute with the expected value:
>>> User.query(first_name="George")
If several arguments are passed, the methods only returns the model
instances that return matches all the argument values:
>>> User.query(first_name="George", last_name="Abitbol")
If the argument value is a collection, the methods will return the
models that matches any of the values:
>>> User.query(first_name=["George", "Jane"])
"""
raise NotImplementedError()
@classmethod
def fuzzy(cls, query, attributes=None, **kwargs):
"""
Works like :meth:`~canaille.backends.models.query` but attribute values
loosely be matched.
"""
raise NotImplementedError()
@classmethod
def get(cls, identifier=None, **kwargs):
"""
Works like :meth:`~canaille.backends.models.query` but return only one
element or :const:`None` if no item is matching.
"""
raise NotImplementedError()
@property
def identifier(self):
"""
Returns a unique value that will be used to identify the model instance.
This value will be used in URLs in canaille, so it should be unique and short.
"""
raise NotImplementedError()
def save(self):
"""
Validates the current modifications in the database.
"""
raise NotImplementedError()
def delete(self):
"""
Removes the current instance from the database.
"""
raise NotImplementedError()
def update(self, **kwargs):
"""
Assign a whole dict to the current instance. This is useful to update
models based on forms.
>>> user = User.get(user_name="george")
>>> user.first_name
George
>>> user.update({
... first_name="Jane",
... last_name="Calamity",
... })
>>> user.first_name
Jane
"""
raise NotImplementedError()
def reload(self):
"""
Cancels the unsaved modifications.
>>> user = User.get(user_name="george")
>>> user.display_name
George
>>> user.display_name = "Jane"
>>> user.display_name
Jane
>>> user.reload()
>>> user.display_name
George
"""
raise NotImplementedError()