烧瓶不稳定的圆形嵌套资源的问题

Question

I have two fields in separate files to marshal with. They are:

from games.controllers.api.categories import category_fields
game_fields = {
    'title': fields.String,
    'developer': fields.String,
    'categories': fields.List(fields.Nested(category_fields)),
    'uri': fields.Url('game')
}

and

from games.controllers.api.games import game_fields
category_fields = {
    'name': fields.String,
    'games': fields.List(fields.Nested(game_fields)),
    'uri': fields.Url('category')
}

When I run the app it throws me an error:

ImportError: cannot import name 'category_fields' from 'games.controllers.api.categories'

Obviously the problem is with circular imports. So how should I solve this?

Btw : the 'developer' part in game_fields shows me " <Developer 1> ". And when I change it to "developer_id": fields.Integer, it gives me developer id with no problem. But I want it to be like "developer": "EA Sports". How can I do this?

Answer 1

A recursive structure like this is bound to give you problems, but if you are decided on it, this is one possible way to avoid circular import errors:

game_fields = {
    'title': fields.String,
    'developer': fields.String,
    'uri': fields.Url('game')
}
from games.controllers.api.categories import category_fields
game_fields['categories'] = fields.List(fields.Nested(category_fields))

category_fields = {
    'name': fields.String,
    'uri': fields.Url('category')
}
from games.controllers.api.games import game_fields
category_fields['games'] = fields.List(fields.Nested(game_fields))

As far as your second question, you haven't described what your Developer class looks like. If you have control over this class, you can change how this class renders itself as a string and make it be the name of the developer instead of <Developer id> .