如何使用 getattr 从模型中获取外键值 [英] How to get foreign key values with getattr from models

问题描述

我有一个模型 Project 并且我正在使用以下指令获取它的属性

I have a model Project and i am getting the attributes of that with the following instr

attr = getattr(project, 'id', None)

project 是实例，id 是字段，None 是默认返回类型.

project is the instance, id is the field and None is the default return type.

我的问题是:如果我想用这个获取外键怎么办?

My question is: what if I want to get the Foreign Key keys with this?

project.customer.name满足以上条件如何获取客户名称?

project.customer.name How to get customer name with the above condition?

if callable(attr):
     context[node][field] = '%s' % attr()

当前代码

context = {'project': {}}
fields = ('id', 'name', 'category', 'created_by', customer)

for field in fields:
    attr = getattr(project, field, None)
        if callable(attr):
            context['project'][field] = '%s' % attr()
        else:
            context['project'][field] = attr

我需要在这里调整客户对象.我可以在我的字段中提供诸如 customer__name 或 customer.name 之类的东西，并且它会填充客户的姓名，但我不确定.

i need to adjust customer object here. that i can give something like customer__name or customer.name in my fields and it get populated with the name of the customer, but i am not sure.

推荐答案

您可以执行以下操作:

def get_repr(value): 
    if callable(value):
        return '%s' % value()
    return value

def get_field(instance, field):
    field_path = field.split('.')
    attr = instance
    for elem in field_path:
        try:
            attr = getattr(attr, elem)
        except AttributeError:
            return None
    return attr

for field in fields:
    context['project'][field] = get_repr(get_field(project, field))

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