angski11422 / python-p4-validation-flask-sqlalchemy-validations-lab

Flask-SQLAlchemy Validations Lab

Learning Goals

• Define constraints and validations in data processing.
• Ensure that only acceptable input is sent to the database using validations.

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Key Vocab

• Constraint: a rule enforced on the data columns of a table. Ensures that only appropriate data is saved to the database.
• Validation: an automatic check to ensure that data entered is sensible and feasible.
• Forms: A web form (or HTML form) is a place where users enter data or personal information that's then sent to a server for processing.

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Introduction

This project has starter code for a couple of models, Author and Post. To get set up, run:

This is a test-driven lab. Run pipenv install to create your virtual environment and pipenv shell to enter the virtual environment.

To generate a database create the migration and from server/ run:

$ flask  db revision --autogenerate -m "<your comment>"
$ flask db upgrade

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Basic Validations

Add validations to these models such that...

1. All authors have a name.
2. No two authors have the same name.
3. Author phone numbers are exactly ten digits.
4. All posts have a title.
5. Post content is at least 250 characters long.
6. Post summary is a maximum of 250 characters.
7. Post category is either Fiction or Non-Fiction.

Then run pytest -x to run your tests. Use these instructions and pytest's error messages to complete your work in the server/ folder.

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Custom Validations

Finally, add a custom validator to the Post model that ensures the title is sufficiently clickbait-y. The validator should add a validation error if the title does not contain:

• "Won't Believe"
• "Secret"
• "Top"
• "Guess"

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Resources

• Changing Attribute Behavior - SQLAlchemy