Extend token payload

[webjunkie]

I'm trying to get custom fields into the JWT payload to make things work with Hasura. I can set a custom jwt_payload function, but I get the problem that there is a hardcoded type TokenPayloadType used everywhere which thus throws an error: __init__() got an unexpected keyword argument.

How can I extend tokens to include custom payload?

[webjunkie]

@KundaPanda can you assist?

[jaydensmith]

Dirty hack that made this work for me for the time being:

app/utils.py

from calendar import timegm
from datetime import datetime

import strawberry

from strawberry_django_jwt.object_types import TokenPayloadType
from strawberry_django_jwt.settings import jwt_settings


def monkey_patch_payload_type():
    fields = {
        'something': (str, '')
    }

    for field, data in fields.items():
        setattr(TokenPayloadType, field, data[1])
        TokenPayloadType.__annotations__[field] = data[0]

    strawberry.type(TokenPayloadType)

    return TokenPayloadType


def jwt_payload(user, _=None):
    username = user.get_username()

    if hasattr(username, 'pk'):
        username = username.pk

    exp = datetime.utcnow() + jwt_settings.JWT_EXPIRATION_DELTA

    payload = {
        user.USERNAME_FIELD: username,
        'exp': timegm(exp.utctimetuple()),
    }

    if jwt_settings.JWT_ALLOW_REFRESH:
        payload['origIat'] = timegm(datetime.utcnow().utctimetuple())

    if jwt_settings.JWT_AUDIENCE is not None:
        payload['aud'] = jwt_settings.JWT_AUDIENCE

    if jwt_settings.JWT_ISSUER is not None:
        payload['iss'] = jwt_settings.JWT_ISSUER

    payload_data = TokenPayloadType(**payload)
    payload_data.something = 'foo bar'

    return payload_data

app/schema.py

import strawberry

from strawberry_django_jwt.middleware import AsyncJSONWebTokenMiddleware
from app.utils import monkey_patch_payload_type

monkey_patch_payload_type()

...

schema = strawberry.Schema(query=Query, mutation=Mutation, extensions=[
    AsyncJSONWebTokenMiddleware,
])

settings.py

GRAPHQL_JWT = {
    ...
    'JWT_PAYLOAD_HANDLER': 'app.utils.jwt_payload',
}

[webjunkie]

Thanks!

I also ended up doing it somewhat dirty, by using jwt_encode and jwt_decode to fiddle with the JWT before/after it hits this library.

This can be overwritten in settings as well like

GRAPHQL_JWT = {
    "JWT_ENCODE_HANDLER": "utils.jwt_payload.jwt_encode",
    "JWT_DECODE_HANDLER": "utils.jwt_payload.jwt_decode",
    ...