Setup Guide

Set Up Flask App

1. Make sure Python 3 is installed:

  python3 --version

If not install it using this command (this will also install pip): Note: Do not install python3.12 as there are issues with pip in that version

  sudo apt-get install python3.11.6 python3-pip
  alias python=python3

2. Create a virtual environment:

  pip install virtualenv
  python -m venv .venv

To use the virtual environment use:

source .venv/bin/activate

To deactivate it use:

deactivate

3. Install all requirements:

pip install -r requirements.txt

4. Run the flask app:

flask --app hello run

Or using an environment variable:

export FLASK_APP=sample
export FLASK_ENV=development
flask run

Setting Up Postgres

Linux(WSL):

First Download Postgres along with postgres-contriblib for some useful tools:

sudo apt install postgresql postgresql-contrib

Then download the python adaptor for postgres psycopg2

1. Download a C compiler, to do so you can use:

sudo apt install build-essential

2. Then make sure libpq header files are installed:

sudo apt install libpq-dev

3. Confirm the pg_config program is installed:

pg_config --version

if there is an error then make sure to add it to path:

export PATH=/usr/lib/postgresql/X.Y/bin/:$PATH

Development Guide

Creating tables for your models

The flask_sqlalchemy module provides a way to easily create a new table for any new models you define:

Open the flask shell by running the following from the root of the project:

flask shell

Then run the following lines:

from reviveme import db
from reviveme import models
db.create_all()

Note that the create_all function won't recreate or update any tables that have already been created. If you make a mistake creating your new model and need to update it, you'll have to drop the table and run db.create_all() again. Avoid doing this to update any models we've already committed though; create a database migration instead.

Creating and Running Migrations

The flask_migrate module allows us to easily generate migrations and run them with ease

To create migration scripts from the app automatically use:

flask db migrate
OR
flask db migrate -m "{table_name} table"

These commands will generate the migration scripts and must be incorporated via source control

To apply the changes use:

flask db upgrade

For more info on using migration commands refer to this blog

Running Scripts

To run scripts from the app use:

python -m reviveme.scripts.{script_to_run}