使用Python的Flask框架构建大型Web应用程序的结构示例

|-flasky
 |-app/
  |-templates/
  |-static/
  |-main/
   |-__init__.py
   |-errors.py
   |-forms.py
   |-views.py
  |-__init__.py
  |-email.py
  |-models.py
 |-migrations/
 |-tests/
  |-__init__.py
  |-test*.py
 |-venv/
 |-requirements.txt
 |-config.py
 |-manage.py

import os
basedir = os.path.abspath(os.path.dirname(__file__))

class Config:
  SECRET_KEY = os.environ.get('SECRET_KEY') or 'hard to guess string' 
  SQLALCHEMY_COMMIT_ON_TEARDOWN = True
  FLASKY_MAIL_SUBJECT_PREFIX = '[Flasky]'
  FLASKY_MAIL_SENDER = 'Flasky Admin <flasky@example.com>' 
  FLASKY_ADMIN = os.environ.get('FLASKY_ADMIN')
  
  @staticmethod
  def init_app(app): 
    pass

class DevelopmentConfig(Config): 
  DEBUG = True

  MAIL_SERVER = 'smtp.googlemail.com'
  MAIL_PORT = 587
  MAIL_USE_TLS = True
  MAIL_USERNAME = os.environ.get('MAIL_USERNAME')
  MAIL_PASSWORD = os.environ.get('MAIL_PASSWORD') 
  SQLALCHEMY_DATABASE_URI = os.environ.get('DEV_DATABASE_URL') or \
    'sqlite:///' + os.path.join(basedir, 'data-dev.sqlite')

class TestingConfig(Config): 
  TESTING = True
  SQLALCHEMY_DATABASE_URI = os.environ.get('TEST_DATABASE_URL') or \
    'sqlite:///' + os.path.join(basedir, 'data-test.sqlite')

class ProductionConfig(Config):
  SQLALCHEMY_DATABASE_URI = os.environ.get('DATABASE_URL') or \
    'sqlite:///' + os.path.join(basedir, 'data.sqlite')

config = {
  'development': DevelopmentConfig,
  'testing': TestingConfig,
  'production': ProductionConfig,
  'default': DevelopmentConfig
}

from flask import Flask, render_template 
from flask.ext.bootstrap import Bootstrap 
from flask.ext.mail import Mail
from flask.ext.moment import Moment
from flask.ext.sqlalchemy import SQLAlchemy 
from config import config

bootstrap = Bootstrap()
mail = Mail()
moment = Moment()
db = SQLAlchemy()

def create_app(config_name):
  app = Flask(__name__) 
  app.config.from_object(config[config_name]) 
  config[config_name].init_app(app)
  
  bootstrap.init_app(app)
  mail.init_app(app)
  moment.init_app(app)
  db.init_app(app)

  # attach routes and custom error pages here
  
  return app

from flask import Blueprint

main = Blueprint('main', __name__) 

from . import views, errors

def create_app(config_name): 
  # ...
  from .main import main as main_blueprint 
  app.register_blueprint(main_blueprint)

  return app

from flask import render_template 
from . import main

@main.app_errorhandler(404) 
def page_not_found(e):
  return render_template('404.html'), 404

@main.app_errorhandler(500) 
def internal_server_error(e):
  return render_template('500.html'), 500

from datetime import datetime
from flask import render_template, session, redirect, url_for

from . import main
from .forms import NameForm 
from .. import db
from ..models import User

@main.route('/', methods=['GET', 'POST']) 
def index():
  form = NameForm()
  if form.validate_on_submit():
    # ...
    return redirect(url_for('.index')) 
  return render_template('index.html',
              form=form, name=session.get('name'),
              known=session.get('known', False),
              current_time=datetime.utcnow())

#!/usr/bin/env python
import os
from app import create_app, db
from app.models import User, Role
from flask.ext.script import Manager, Shell
from flask.ext.migrate import Migrate, MigrateCommand

app = create_app(os.getenv('FLASK_CONFIG') or 'default') 
manager = Manager(app)
migrate = Migrate(app, db)

def make_shell_context():
  return dict(app=app, db=db, User=User, Role=Role)

manager.add_command("shell", Shell(make_context=make_shell_context))
manager.add_command('db', MigrateCommand)

if __name__ == '__main__': 
  manager.run()

(venv) $ pip freeze >requirements.txt

Flask==0.10.1
Flask-Bootstrap==3.0.3.1
Flask-Mail==0.9.0
Flask-Migrate==1.1.0
Flask-Moment==0.2.0
Flask-SQLAlchemy==1.0
Flask-Script==0.6.6
Flask-WTF==0.9.4
Jinja2==2.7.1
Mako==0.9.1
MarkupSafe==0.18
SQLAlchemy==0.8.4
WTForms==1.0.5
Werkzeug==0.9.4
alembic==0.6.2
blinker==1.3
itsdangerous==0.23

(venv) $ pip install -r requirements.txt

import unittest
from flask import current_app 
from app import create_app, db

class BasicsTestCase(unittest.TestCase): 
  def setUp(self):
    self.app = create_app('testing')
    self.app_context = self.app.app_context()
    self.app_context.push()
    db.create_all()

  def tearDown(self): 
    db.session.remove() 
    db.drop_all() 
    self.app_context.pop()

  def test_app_exists(self): 
    self.assertFalse(current_app is None)

  def test_app_is_testing(self): 
    self.assertTrue(current_app.config['TESTING'])

@manager.command
def test():
  """Run the unit tests."""
  import unittest
  tests = unittest.TestLoader().discover('tests') 
  unittest.TextTestRunner(verbosity=2).run(tests)

(venv) $ python manage.py test

test_app_exists (test_basics.BasicsTestCase) ... ok
test_app_is_testing (test_basics.BasicsTestCase) ... ok

.----------------------------------------------------------------------
Ran 2 tests in 0.001s

OK

(venv) $ python manage.py db upgrade