Reusable CRUD

I would like to build a reusable CRUD view class on top of flask-rest-api. I built one previously fairly close to flask-restful’s design, and was wondering if anything currently exists or you have tips or suggestions of how to proceed.

The problem I am trying to solve is building the same list/get/update/delete endpoints over and over for various DB models. I want to declare things like access controls, default schema for serialization, what fields are permitted to update, DB model class, relationships to prefetch (i.e. joinedload) for list view, and auto-registration of endpoints via __init_subclass__.

Anything you’d suggest or like to see? Anything like this exist already on top of flask-rest-api?

[revmischa]

I get what you mean about needing to override details. I’ve worked with these libraries before in both perl and python, and it’s mostly a matter of creating a base class and defining the parameters you mention in class vars, and then having default implementations of the methods list, get, create, update, delete.

[zedrdave]

@lafrech Dunno whether to reopen this or start a new thread.

I ran into something similar a while back and did end up creating my own CRUD blueprint class. Would be happy to try and refactor it into something usable in flask-smorest, if you think this might be of interest.

My approach is similar to @revmischa above (with a few differences)…

• a CRUD class that inherits from flask-smorest’s Blueprint
• take a number of class/var names as arguments to define Model, Argument/Response Schema, key etc. With some good default in place (camelcased endpoint name + “Schema” etc) which make it seamless for most cases.
• relying on sqlalchemy for DB operations (I did once implement a variant that handled MongoDB, so both might be possible, but half the code would differ).
• access control is handled separately (I use decorators on classes/endpoints with a permission/rule system) and added to the CRUD class as callbacks.

I think an access-control framework, and a CRUD class, would be two really useful additions to smorest, and decrease cruft/code-repetition hugely. Maybe worth workshopping the needs/implementation details before working on a Pull Request…