Multi-Language Contact Form

Build a simple web application that displays a contact form with internationalization support for English and Spanish. The form should validate user input and display error messages in the user's preferred language.

Requirements

Create a Flask application with the following features:

1. Language Selection: Support two languages - English (en) and Spanish (es). The application should detect the language from a query parameter lang (e.g., /contact?lang=es), defaulting to English if not specified.

2. Contact Form: Create a form with the following fields:

   • Name (required, text input)
   • Email (required, must be a valid email address)
   • Message (required, text area, minimum 10 characters)
   • Submit button

3. Validation Messages: When the form fails validation, error messages should be displayed in the appropriate language:

   • For English: Use standard English validation messages
   • For Spanish: Display Spanish translations of validation messages

4. Form Rendering: Create a template that displays the form and shows validation errors when present.

Implementation Notes

• The application should have a single route /contact that handles both GET (display form) and POST (process submission) requests
• On successful form submission, display a success message in the appropriate language
• Use appropriate internationalization practices for form validation messages

Test Cases

• Submitting an empty form displays validation error messages in English by default @test
• Submitting an empty form with ?lang=es displays validation error messages in Spanish @test
• Submitting a valid form shows a success message in the correct language @test
• Submitting a form with an invalid email address shows an email validation error in the correct language @test

@generates

Dependencies { .dependencies }

Flask-WTF { .dependency }

Provides form handling and CSRF protection for Flask applications.

Flask-Babel { .dependency }

Provides internationalization and localization support for Flask applications.