Pre-Populate a WTforms in flask, with data from a SQLAlchemy object

flask, flask-sqlalchemy, flask-wtforms, python

Solution

You need to pass your object to the form when you create it.

form = EditProfile(obj=user)  # or whatever your object is called

You're going to run into some trouble with

          query = EditProfile(form.username.data,
                             form.email.data,
                             form.about.data,
                             form.website.data,
                             )
          db.session.add(query)

It creates a new instance of your `EditProfile` form. You then try to add it to the session. The session wants models, not forms.

Instead, after validating the form, you can associate its values with the object.

form.populate_obj(user)  # or whatever your object is called

Because your object was already loaded, you won't need to add it to the session. You can remove `db.session.add(query)` and just call `db.session.commit()`.

Problem

I am fairly new to flask framework and was creating an edit profile page for a webportal. I am stuck at a point and am unable to autofill a form. Here is my form class : ``` class EditProfile(Form): username = TextField('Username', [Required()]) email = TextField('Email', [Required()]) about = TextAreaField('About', [Required()]) website = TextField('Website', [Required()]) ``` This is my function that evaluates the form. ``` def editprofile(nickname = None): if g.fas_user['username'] == nickname or request.method == 'POST': form = EditProfile() form_action = url_for('profile.editprofile') if request.method == 'POST' and form.validate(): if form.username.data == nickname : query = EditProfile(form.username.data, form.email.data, form.about.data, form.website.data, ) print query #debug db.session.add(query) db.session.commit() flash('User Updated') print "added" return(url_for('profile.editprofile')) return render_template('profile/add.html', form=form, form_action=form_action, title="Update Profile") else: return "Unauthorised" ``` And my html template for form is form is : ``` {% extends "base.html" %} {% block title %} {{ title }} {% endblock %} {% block content %} {% from "_formhelpers.html" import render_field %} <div id="Edit Profile"> <h2>{{ title }}</h2> <form method="post" action="{{ form_action }}"> <fieldset> <legend></legend> {{ render_field(form.username) }} {{ render_field(form.email)}} {{ render_field(form.about )}} {{ render_field(form.website) }} </fieldset> <input type="submit" class="button" value="Save"/> </form> </div> {% endblock %} ``` I have an object, of user class. And from that object I want to prefill this form.How can I prepopulate the values in the form. I am trying to implement the edit profile functionality here.

Original source