Flask WTF form not updating with the sqlite3 database

Question

I have a RadioField form item that uses values for its field from the database.

If the database is not created I cannot start the Flask Webserver even though it should only access the database when I go to that page and load that form.

If I update the database while the Webserver is running I don't see the form with the new database information.

Until I restart the Flask webserver.

How can I get it so that it forces the form to reload its values from the database when you visit the page.

Also I am pretty sure it is storing the values of the RadioField in memory since I can delete the database and the Flask Webserver will continue running and the RadioField will still be shown.

I am using a sqlite3 database and reading and writing to it with APSW(another python sqlite3 wrapper)

This is my Form

class DatabaseForm(Form):
    listOfRows = db.getDatabase()
    rows = [(str(x[0]), x) for x in listOfRows]
    images = RadioField('images', validators = [Required()], choices = rows)

Here is my View

@app.route('/database', methods = ['GET', 'POST'])
def database():
    ''' displays the database and allows the user to select an entry '''
    form = DatabaseForm()
    if form.validate_on_submit():

        primaryKey = form.images.data
        primaryKey = int(primaryKey)


        myProgram.start(primaryKey)
        return render_template('simple.html', word = "SUCCESS")
    else:
        print form.errors

    return render_template('database.html', form=form)

Answer 1

You should set the field choices in the view:

    form = DatabaseForm()
    form.images.choices = [(str(x[0]), x) for x in listOfRows]
    if form.validate_on_submit():

By setting them once on the class the options are only set when the class is instantiated, so they wont reflect any changes made during the lifetime of that particular process.