How To Get Values From Nested Pydantic Classes?

class mail(BaseModel): mailid: int email: str class User(BaseModel): id: int name: str mails: List[mail] data = { 'id': 123, 'name': 'Jane Doe',

Solution 1:

It looks like you are trying to access the class rather than the instance.

Here's one way of doing it:

from pydantic import BaseModel
from typing import List

class Mail(BaseModel):
    mailid: int
    email: str

one_mail = {"mailid": 1, "email": "aeajhs@gmail.com"}

mail = Mail(**one_mail)

print(mail)
# mailid=1 email='aeajhs@gmail.com'

With that in place, let's adapt the User model:

class User(BaseModel):
    id: int
    name: str
    mails: List[Mail]

data = {
    "id": 123, 
    "name": "Jane Doe",
    "mails":[
        {"mailid": 1, "email": "aeajhs@gmail.com"}, 
        {"mailid": 2, "email": "aeajhsds@gmail.com"}
    ]
}

userobj = User(**data)

print(userobj.mails)
# [Mail(mailid=1, email='aeajhs@gmail.com'), Mail(mailid=2, email='aeajhsds@gmail.com')]

If you only need one of the email addresses, you need to specify which one, e.g.:

print(userobj.mails[0].email)
# aeajhs@gmail.com

In order to get a list of all email addresses, you need to iterate over the mails, e.g.:

print([mail.email for mail in userobj.mails])
# ['aeajhs@gmail.com', 'aeajhsds@gmail.com']

An as a side note: Pydantic supports email string validation.

Solution 2:

The error

AttributeError: 'list' object has no attribute 'email'

means you are accessing an attribute of the mails list, not mail object.

You should pick the object from the list first using an index:

print(userobj.mails[0].email)

And, if you want every email of every mails instance, do

print([mail.email for mail in userobj.mails])