[Flask-Security] ObjectId is not JSON serializable on login

import datetime
from bson.objectid import ObjectId
from mongoengine.base import BaseDocument
from mongoengine.queryset.base import BaseQuerySet

class MongoJsonEncoder(JSONEncoder):
    def default(self,obj):
        if isinstance(obj, (datetime.datetime, datetime.date)):
            return obj.isoformat()
        elif isinstance(obj, ObjectId):
            return str(obj)
        elif isinstance(obj,BaseDocument):
            return json_util._json_convert(obj.to_mongo())
        elif isinstance(obj,BaseQuerySet):
            return json_util._json_convert(obj.as_pymongo())
        return JSONEncoder.default(self, obj)

app = Flask(__name__)
app.json_encoder = MongoJsonEncoder

You need to fork flask_security project from Github and change flask_security/decorators.py

• In def _check_token():

  • Change: identity_changed.send(app, identity=Identity(user.id))
  • To: identity_changed.send(app, identity=Identity(str(user.id)))

• In def _check_http_auth():

  • Change: identity_changed.send(app, identity=Identity(user.id))
  • To: identity_changed.send(app, identity=Identity(str(user.id)))