WTForms: Creating an edit profile form that ensures the password is the valid password for the user?

Question

In my twitter-like app, I want to allow users to edit their profiles. If the password the user submits in the edit form is not the valid password, my app should flash a message ("Wrong password") and redirect to the homepage.

What I'm having trouble with is the form ensuring that the submitted password is the valid password. Here's what I have so far:

class EditProfileForm(FlaskForm):
"""Edit form"""   

username = StringField('Username', validators=[DataRequired()]) 
email = StringField('E-mail', validators=[DataRequired(), Email()])
image_url = StringField('(Optional) Image URL')
header_image_url = StringField('(Optional) Image URL')
bio = StringField('(Optional) Bio')
password = PasswordField('Password')

def __init__(self, user, *args, **kwargs):
    super(EditProfileForm, self).__init__(*args, **kwargs)
    self.user = user

def validate_password_proof(self, field):
    if form.data != self.user.password:
        raise ValidationError('Wrong password.') 

I found this validator method from another post, but I can't figure out how to properly initialize the form ('user' is not defined):

@app.route('/users/profile', methods=["GET", "POST"])
def profile():
"""Update profile for current user."""

if not g.user:
    flash("Access unauthorized.", "danger")
    return redirect("/")

form = EditProfileForm(user)  

return render_template()  

If anyone has another solution to ensure the password is the correct password or can point out how I'm misusing the above I'd appreciate it!

Answer 1

Do this to the validator:

def validate_password(self, password):
    if password.data != get_user_byEmail(self.email.data):
        raise ValidationError('Wrong password.')

of course you have to implement get_user_byEmail(email: str)

in the route pass the form to the template

return render_template('templateName')