How to jsonify objects from sqlalchemy?

Question

I\'m using Flask, SQLAlchemy and javascript. I need to pass the results of my query to javascript in the json format, through AJAX, but I keep getting this error:

Answer 1

Using marshmallow-sqlalchemy schemas, I'm generating an object and returning the serializable JSON object as a native method for the model. Here is an example for a class of Customer in SQLAlchemy model.

from models import db
import datetime
from marshmallow_sqlalchemy import ModelSchema

class Customer(db.Model):
    __tablename__ = 'customers'
    __table_args__ = {'schema': 'abc_schema'}
    id = db.Column(db.String(255), primary_key=True)
    created_at = db.Column(db.DateTime, default=datetime.datetime.utcnow)
    firstName = db.Column(db.String())
    lastName = db.Column(db.String())
    def __getitem__(self, item):
        return getattr(self, item)

    ## Making the sql alchemy object JSON serailizable
    def JSONSerializableObj(self):
        class BaseSchema(ModelSchema): 
            def on_bind_field(self, field_name, field_obj):
                field_obj.allow_none = True

        class ObjectSchema(BaseSchema): 
            class Meta:
                model = self

        object_schema = ObjectSchema()
        return object_schema.dump(self).data

This way, I'm just reusing this snippet for all models and using the JSONSerializableObj