worqlyfe (4 person)

Flask Template

version 0.0.1 (alpha)

Development

Make a fork before cloning

Install dependencies

• Python 3.7.2 was tested
• Postgresql 10.3 was tested

1. Delete peewee-db-evolve==3.7.0 from requirements.txt during the first installation. Because of how peewee-db-evolve created it's build process, we would first need to delete it.
2. Run:

   pip install -r requirements.txt
   

3. Now add peewee-db-evolve==3.7.0 back into requirements.txt
4. Run again:

   pip install -r requirements.txt
   

If you're having trouble installing dependencies

• Remove certifi==2018.11.29 from requirements.txt

If you're having trouble starting flask

• Restart your terminal as well and reactivate conda source

Create a .env file at the root of the directory

This project uses python-dotenv. When running commands using flask, environment variables from .env are automatically loaded.

When executing python scripts directly e.g. python start.py, environment variables are not loaded and will not work except python migrate.py (read the script - migrate.py to know why it would load the environment variables .env)

Minimum environment variables that needs to be set

FLASK_APP='start' # based on the name of our entry point script
FLASK_ENV='development' # use this in development, otherwise 'production' or 'test'
DATABASE_URL="postgres://localhost:5432/nextagram_dev"
SECRET_KEY= #generate your own key

Use os.urandom(32) to generate a random secret key and paste that in .env. It's important to keep this SECRET_KEY private.

Since this app uses Pooled Connections, you may also want to set:

DB_TIMEOUT=300 # 5 minutes
DB_POOL=5

(see database.py)

Create a Database

• this application is configured to use Postgresql

createdb nextagram_dev

*if you name your database something else, tweak the settings in .env

Ignoring Files from Git

Before git commiting, remember to ignore key files. Here's an example of .gitignore

.vscode
*.DS_Store
*__pycache__
*.env

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Database Migrations

python migrate.py

*this template is configured to use Peewee's PooledConnection, however, migrations using Peewee-DB-Evolve doesn't work well. A hack was used to not use PooledConnection when running migration. Pending investigation. There are no known side effects to run this template in production.

Starting Server

flask run

Starting Shell

flask shell

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Deploying to Production

• ensure environment variables are configured appropriately
• migrations will not run in interactive mode when FLASK_ENV is set to 'production'
• It's important to set your own SECRET_KEY environment variable and keep that private.

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Architecture

This template separates out API and Web to separate packages. Both API and Web are configured to use Flask's Blueprints.

All new models should go into it's own file/script within the models directory.

The entry point for a Flask server to start is located at start.py

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Dependencies

This template was created against Python 3.7. Should work with newer versions of Python. Not tested with older versions.

Peewee is used as ORM along with a database migration library peewee-db-evolve.

This template also comes packaged with Bootstrap 4.1.3 and it's dependencies (jQuery).

A copy of requirements.txt is included in the repository.

autopep8==1.4.3
certifi==2018.11.29
Click==7.0
colorama==0.4.1
Flask==1.0.2
Flask-Cors==3.0.7
itsdangerous==1.1.0
Jinja2==2.10
MarkupSafe==1.1.0
peewee==3.8.2
peewee-db-evolve==3.7.0
psycopg2-binary==2.7.7
pycodestyle==2.5.0
python-dotenv==0.10.1
six==1.12.0
Werkzeug==0.14.1

Remove certifi==2018.11.29 if you're having trouble installing dependencies.