CS1999 Tech notes

Notes to explain how to do (and understand) project tasks.

Especially for phase 0

For task 0-RUN:

• using virtual environments
• using localhost (or: why isn't 0.0.0.0 working?)

Things that are useful from the start

Your buggy editor is a webserver...

• what is a webserver?
• ...then: how Flask works as a webserver

Debugging tips:

• use print()
• “error in update operation” or problems saving to the database

General set-up:

• how to set FLASK_ENV

Adding comments to your code:

• comments in Python and HTML... and more

Especially for phase 1

Notes for task 1-TEMPLATE: Add a new template to the app:

• templates in Flask (where the HTML comes from)
• routes in Flask (how it picks the right template)

Notes for task 1-ADD: Add more data to the form:

• identify the template to edit
• add input tag to the form
• handle the POST request
• know what's in the database
• add new data: CREATE TABLE
• add new data: ALTER TABLE

More general things for once you've got going

Notes to overcome CSS not changing when you hit refresh (may help with 1-STYLE):

• static vs. dynamic
• cache-busting the CSS

Notes for using Flask's flash messages:

• setting a secret key (also: how cookies work)
• flash messages

How to add images to your Flask app:

• adding static content