Deserialize Association Objects

Hi,

I’ve created an Association Table as described in the SQLAlchemy manual, however when I try to load on a POST request I get this response:

RuntimeError: Model <class 'app.products.models.SoldProducts'> has multiple primary keys

Which is true, as the association table creates a compound key. How should I proceed?

Thanks!

[maitham]

Would it be possible to provide a example for such models?

class Skill(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(255), unique=True, nullable=False)
    users = db.relationship("Proficiency", back_populates="skill", lazy=True)

    def __repr__(self):
        return "<Skill %r>" % self.name

class Proficiency(db.Model):
    user_id = db.Column(db.Integer, db.ForeignKey("user.id"), primary_key=True)
    skill_id = db.Column(db.Integer, db.ForeignKey("skill.id"), primary_key=True)
    score = db.Column(db.Integer(), nullable=False)

    skill = db.relationship("Skill", back_populates="users")
    user = db.relationship("User", back_populates="skills")

    def __repr__(self):
        return "<Proficiency %r>" % self.score

class User(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(80), unique=True, nullable=False)
    skills = db.relationship("Proficiency", back_populates="user", cascade="all,delete")

    def __repr__(self):
        return "<User %r>" % self.name

[antgel]

@tmeloliveira I’m a bit late here, but did https://marshmallow.readthedocs.io/en/stable/nesting.html not help?