flask-admin: How to display meaningful foreign key info in edit and create forms?

Question

I have a Flask-Admin interface to a flask app using SQLAlechemy, and I can't seem to figure out how to handle foreign keys. Specifically, I have the following two models:

class DoctorType(db.Model):
    __tablename__ = 'doctor_type'
    id = db.Column(db.Integer, primary_key=True)
    doctor_type_english_name = db.Column(db.Unicode(255))
    doctors = db.relationship('Doctor')

    def __unicode__(self):
        return self.doctor_type_english_name

class Doctor(db.Model):
    __tablename__ = 'doctor'
    id = db.Column(db.Integer, primary_key=True)
    doctor_english_name = db.Column(db.Unicode(255))
    doctor_type_id = db.Column(db.Integer, db.ForeignKey('doctor_type.id'))

    def __unicode__(self):
        return self.doctor_english_name

I'd like for the doctor_type_id field in the create or edit forms of flask-admin to be a dropdown list of doctor_type_english_name rather than just being an integer input like this:

Doctor Type Input Field

I have __unicode__ functions on the models (I'm using python 2.7). I tried tinkering with form_ajax_refs in my custom form views but with no success. Any help would be much appreciated!

Jessiejessika

Answer 1

It turns out what I was missing was a relationship from the Doctor class to the DoctorType class. I implemented this with a backref in the DoctorType.doctors relationship:

class DoctorType(db.Model):
    __tablename__ = 'doctor_type'
    id = db.Column(db.Integer, primary_key=True)
    doctor_type_english_name = db.Column(db.Unicode(255))
    doctors = db.relationship('Doctor', backref='doctor_type')

    def __unicode__(self):
        return self.doctor_type_english_name

Once I added that, the "Doctor" edit and create forms in flask-admin had a new field called Doctor Type that was a dropdown of the DoctorType.doctor_type_english_name values, and the Doctor Type ID field was gone by default. This is the behavior I was wanting.

Jessiejessika

Answer 2

Implement __repr__ in define of data model.

class DoctorType(db.Model):
    #...
    def __repr__(self):
        return self. doctor_type_english_name

Ribal

Adding __repr__ would not help since that does the same thing as the __unicode__ function in this case. The foreign key still shows up as an integer field in the edit and delete forms. Thanks for the speedy response though! – Jessiejessika

Have you try implement __repr__ in your model define? __repr__ and __unicode__ both works for me. – Ribal

I did. I realized it was the relationship that was missing, not the __repr__. Thanks again for the answer though! I upvoted your answer but I don't have enough rep to upvote anything yet :-( – Jessiejessika

This is wonderful. It works like a charm, with so little code! – Emeryemesis