wtforms-json

from wtforms import Form, StringField, IntegerField from wtforms.validators import DataRequired, NumberRange from wtforms_json import init_app # Initialize wtforms-json to extend WTForms functionality init_app() class UserProfileForm(Form): name = StringField('Name', validators=[DataRequired()]) age = IntegerField('Age', validators=[NumberRange(min=0, max=120)]) # Example JSON data (e.g., from a request body) valid_json_data = {'name': 'Jane Doe', 'age': 25} invalid_json_data = {'name': '', 'age': 150} # Name missing, age out of range print("--- Processing valid data ---") form_valid = UserProfileForm() form_valid.from_json(valid_json_data) # Populate form from JSON if form_valid.validate(): print(f"Form is valid. Data: {form_valid.data}") else: print(f"Form errors: {form_valid.errors}") print("\n--- Processing invalid data ---") form_invalid = UserProfileForm() form_invalid.from_json(invalid_json_data) if form_invalid.validate(): print(f"Form is valid. Data: {form_invalid.data}") else: print(f"Form errors: {form_invalid.errors}")