UrlForMixin now offers a url property (resolves #193)

[jace]

No description provided.

[jace]

Several models have a url column. The column will override the property, but we'll have to careful about unintended mixups and should consider renaming those columns.

https://github.com/search?q=org%3Ahasgeek+%22url+%3D+db.Column%22&type=Code

[jace]

I'm a little concerned about forcing a url property to be available on all models just because UrlForMixin is a base class of BaseMixin. We need this to be more intent-based:

RoleMixin should look for a dictionary named proxy_properties or __proxy_properties__ mapping names to functions. These will be made available in the proxy as properties.

Syntax 1 (read-only properties):

class MyModel(BaseMixin, db.Model):
    proxy_properties = {
        'url': lambda self: self.url_for(),
        }

Syntax 2 (read/write, but verbose):

class MyModel(BaseMixin, db.Model):
    proxy_properties = {
        'url': {'get': lambda self: self.url_for()},
        }

Neither syntax offers a way to declare what roles these properties are available under. Presumably, that will be left to __roles__.

On the other hand, if url turns out to be widely used property, this syntax is unnecessary verbiage in all models. We could take yet another approach: a new mixin dedicated to adding URL properties:

class UrlPropertyMixin(object):
    @with_roles(read={'all'})
    @property
    def url(self):
        return self.url_for()

Models that need url can simply inherit from this class. Other models are not affected.

[iambibhas]

I like the UrlPropertyMixin idea but can we call it absolute_url instead of url? And let it be available to all models? I'm getting the idea from Django where each model has a get_absolute_url() method that's used internally in Django whenever a url is needed for a model. It can be overridden as well. https://docs.djangoproject.com/en/2.1/ref/models/instances/#get-absolute-url

This lets us get out of this url name confusion.

[jace]

If we call it absolute_url, it doesn't need to be in a separate mixin.

[jace]

Renamed. Good to merge, @iambibhas?