Question

I have an embedded document class Post and a father-class Thread.

class Thread(Document):
    ...
    posts = ListField(EmbeddedDocumentField("Post"))

class Post(EmbeddedDocument): 
    attribute = StringField()
    ...

I want to create a new post and add it to my ListField in the Thread class.

My code looks like this:

post = Post()
post.attribute = "noodle"
post.save()
thread.posts.append(post)
thread.save()

But I get the following error message:

“‘Post’ object has no attribute ‘save'”

If I skip the post.save() an empty Post object is appended to my Thread.

Any ideas?

Answer 1

Your code looks fine – are you sure you don’t have other thread objects? Heres a test case proving your code (without the post.save() step). What version do you have installed?

import unittest
from mongoengine import *


class Test(unittest.TestCase):

    def setUp(self):
        conn = connect(db='mongoenginetest')

    def test_something(self):

        class Thread(Document):
            posts = ListField(EmbeddedDocumentField("Post"))

        class Post(EmbeddedDocument):
            attribute = StringField()

        Thread.drop_collection()

        thread = Thread()
        post = Post()
        post.attribute = "Hello"

        thread.posts.append(post)
        thread.save()

        thread = Thread.objects.first()
        self.assertEqual(1, len(thread.posts))
        self.assertEqual("Hello", thread.posts[0].attribute)