在 Django 中序列化一棵树 [英] Serializing a tree in Django

问题描述

有没有简单的方法来序列化由模型给出的树，例如下面显示的类别?

is there any simple way to serialize a tree given by a model such as the Category shown below?

我想得到一个 json 对象，例如:

I'd like to get a json object like:

[ { 'name': 'cat1',
    'children': [ { 'name': 'cat11',
                    'children': [ ... ]
                ]
  }
  ...
]

谢谢

class Category(MPTTModel):
    name = models.CharField(max_length=50, unique=True)
    parent = models.ForeignKey('self', null=True, blank=True, related_name='children')
    order_key = models.IntegerField()

    class Meta:
        verbose_name_plural = 'Categories'

    class MPTTMeta:
        order_insertion_by = ['order_key']

    def __unicode__(self):
        return "%s" %(self.name)

推荐答案

我认为您必须遍历树，并构建一个使用 JSON 序列化的对象.我假设你的树是非循环的，否则它会变得更复杂.我还没有测试过这个，但这样的事情会起作用(只要你确定你没有周期):

I think you'll have to walk the tree, and build an object which you serialize using JSON. I'm assuming your tree is acyclic, because otherwise it gets more complicated. I haven't tested this, but something like this will work (as long as you're sure you don't have cycles):

def serialize_to_json(self):
    return json.dumps(self.serializable_object())

def serializable_object(self):
    "Recurse into tree to build a serializable object"
    obj = {'name': self.name, 'children': []}
    for child in self.get_children():
        obj['children'].append(child.serializable_object())
    return obj

(不记得 children_set 是否是获取孩子列表的正确方法.如果这是错误的，请评论.)

(Can't remember if children_set is the right way to get the list of children. Please comment if this is wrong.)

这篇关于在 Django 中序列化一棵树的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！