Python “InterfaceError: (sqlite3.InterfaceError) Error binding parameter 1 - probably unsupported type.”

Question

I am trying to post to the database but I am getting a "sqlalchemy.exc.InterfaceError". I am using Flask/ flask_sqlalchemy extension.

Models.py

class Link(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    original_url = db.Column(db.String(512))
    shorten_url = db.Column(db.String(14), unique=True)
    visits = db.Column(db.Integer, default=0)
    date_created = db.Column(db.DateTime, default=datetime.now)

    #  inheritance
    def __init__(self, **kwargs):
        super().__init__(**kwargs)
        self.shorten_url = self.create_short_link

    def create_short_link(self):
        characters = string.digits + string.ascii_letters 
        shorten_url = ''.join(choices(characters, k=3))

        link = self.query.filter_by(shorten_url=shorten_url).first()

        if link: 
           return self.create_short_link

        return shorten_url

Routes.py

@short.route('/add_link', methods=['POST'])
def add_link():
        original_url = request.form['original_url']
        link = Link(original_url=original_url)
        db.session.add(link)
        db.session.commit()

        return render_template('link_added.html',
          new_link=link.shorten_url, original_url=link.original_url)

Traceback

sqlalchemy.exc.InterfaceError: (sqlite3.InterfaceError) Error binding parameter 1 - probably unsupported type. [SQL: INSERT INTO link (original_url, shorten_url, visits, date_created) VALUES (?, ?, ?, ?)]

Dave W. Smith Dave W. Smith · Accepted Answer · 2019-10-29T02:07:25

Instead of

self.shorten_url = self.create_short_link

try

self.shorten_url = self.create_short_link()

The error might be pointing out that a function isn't a supported type.

Python “InterfaceError: (sqlite3.InterfaceError) Error binding parameter 1 - probably unsupported type.”

1 Answers