Flask-Mold

Flask Application Boilerplate

Boilerplate codes to help getting started with Flask faster. Batteries included. Manage database migration with Alembic.

Get Started

Get the source and setup the environment

git clone https://github.com/kates/flask-mold.git
cd flask-mold
virtuanenv --distribute .venv
source .venv/bin/activate
pip install -r requirements.txt

Update config.py

# in config.py

SQLALCHEMY_DATABASE_URI = "postgresql://demo:demo@localhost/demodb"

Initialize alembic

python manage.py migration init

Update the generated alembic.ini with the same db uri as in the config.py

# in alembic.ini

sqlalchemy.url = postgresql://demo:demo@localhost/demodb

Create migration file

python manage.py migration create create_users

Edit the migration file created above

# in XXXXXX_create_users.py

"""create_users
Revision ID: 71f880c1c35
Revises: None
Create Date: 2012-10-20 14:22:02.857840
"""

# revision identifiers, used by Alembic.
revision = '71f880c1c35'
down_revision = None

from alembic import op
import sqlalchemy as sa

def upgrade():
    op.create_table("users",
    	sa.Column("id", sa.Integer, primary_key=True),
    	sa.Column("name", sa.String(50), nullable=False),
    	sa.Column("dept", sa.String(50)),
    	)

def downgrade():
    op.drop_table("users")

Run the migration:

python manage.py migration up

Update the models.py to reflect the db schema

# in models.py

class User(db.Model):
	__tablename__ = "users"

	id = db.Column("id", db.Integer, primary_key=True)
	name = db.Column("name", db.String(50), nullable=False)
	dept = db.Column("dept", db.String(10))

Create a blueprint inside blueprints with the following structure

home
├── __init__.py
├── blueprint.py
└── templates
    └── index.html

by running the blueprint generator

python manage.py blueprint home

Update the blueprint

# in blueprints/home/home_blueprint.py

from flask import Blueprint
from flask import render_template
from flask import abort
from flask import request
from flask import redirect

from flask import url_for from plugins.db import db from models import User

view = Blueprint("home", __name__, template_folder="templates")

@view.route("/")
def index():
	users = User.query.order_by("id desc").all()
	return render_template("index.html", users=users)

@view.route("/create_user", methods=["POST"])
def new_user():
	name = request.values.get("name")
	dept = request.values.get("dept")
	user = User()
	user.name = name
	user.dept = dept

	db.session.add(user)
	db.session.commit()

	return redirect("/")

Write the index.html

# in blueprints/home/templates/index.html

<h1>Home</h1>

<ul>
	{% for user in users %}
	<li>{{ user.name }} - {{ user.dept }}</li>
	{% endfor %}
</ul>

<form method="POST" action="/create_user">
	<div>
		<label>Name: <input type="text" name="name" /></label>
	</div>

	<div>
		<label>Dept: <input type="text" name="dept" /></label>
	</div>

	<div>
		<input type="submit" value="Submit" />
	</div>
 </form>

Run the server

python manage.py runserver

Point your browser to http://localhost:5000

Plugins

TODO: Flask extensions can be used directly but code may be organized through plugins.

Shell

The manage.py script includes a shell command that you can use to quickly view or manipulate your model.

Running

python manage.py shell

will put you into the python shell with you application and db context loaded.

>>> from models import User                    
>>> user = User()                              
>>> user.name = "John Doe"                     
>>> user.dept = "Finance"                      
>>> db.session.add(user)                       
>>> db.session.commit()                        
>>> users = User.query.all()                   
>>> [[user.name, user.dept] for user in users] 
[[u'John Doe', u'Finance']]                    

TODO

• Write guide to testing