Flask is a microframework for Python that provides common tools and patterns for building web applications but does not enforce any specific project structure. It includes the Werkzeug WSGI toolkit and Jinja templating engine. Flask emphasizes simplicity and flexibility by providing basic application object and request context while allowing developers to choose extensions and build application-specific solutions. It is well-suited for Google App Engine by providing a Flask application object that can be deployed to GAE and extensions that integrate authentication and maps.

1. + Google

2. Who?
CADEMY
Bruno Rocha
bruno@rocha.com
http://github.com/rochacbruno
http://twitter.com.rochacbruno
http://brunorocha.org
http://pythonhub.com
www.quokkaproject.org

3. Full Stack
Framework
Faz as escolhas por você e oferece uma
plataforma completa
Micro Framework
Define apenas o básico
(WSGI, request, response, session etc)
(ORM, Templates, Organização de arquivos,
arquivos de configurações, etc)
+ Fácil
- controle
Crescimento gradativo
+ trabalhoso
+ controle

4. What The Flask?
Flask is a microframework for Python based
on Werkzeug, Jinja 2 and good intentions.

5. Werkzeug - WSGI library
from werkzeug.serving import run_simple
from werkzeug.wrappers import Request, Response
@Request.application
def application(request):
return Response('Hello World!')
run_simple('localhost', 4000, application)

6. Jinja - Template engine
{% macro render_user(user) %}
<li><a href="{{ user.url }}">{{ user.username }}</a></li>
{% endmacro %}
{% from _above_file.html import render_user %}
<title>{% block title %}{% endblock %}</title>
<ul>
{% for user in users %}
{{ render_user(user) }}
{% endfor %}
</ul>

7. Good intentions.
# thread locals
from flask import request, session, g
# extensions
from flask.ext import AmazingExtension
# blueprints
from flask import Blueprint
blog = Blueprint(“blog_blueprint”)
blog.template_folder = “path/to/folder”
blog.static_folder = “path/to/static”
# Application factory
app = create_app(**kwargs)
app.register_blueprint(blog)
AmazingExtension(app)

8. It is not a framework, it is a pattern!
Good intentions
flask.ext.*
your_app.py

9. your_app.py
$ pip install flask, flask-security, flask-admin, xpto-orm
from
from
from
from
from
flask import Flask
flask.ext.security import Security
flask.ext.admin import Admin
somewhere.db.models import UserDatastore
somewhere.views import indexpage
def create_app(**config):
app = Flask(“myapp”)
app.config_from_object(config)
Admin(app)
Security(app, UserDatastore)
app.add_url_rule(“/index/<something>”, view_func=indexpage)
return app
if __name__ == “__main__”:
app = create_app(SECRET_KEY=”XYZ”)
app.run()

10. Blueprints
Um Blueprint funciona de forma similar a um objeto Flask, mas na verdade não
é uma aplicação, mas sim um projeto de como construir ou extender uma
aplicação
from flask import Blueprint, render_template
blog_extension = Blueprint(“my_blog_extension”)
blog_extension.endpoint = “/blog”
blog_extension.template_folder = “path/to/blog_templates”
blog_extension.static_folder = “path/to/blog_static”
@blog_extension.route(“/index”)
def blog():
posts = some_db_or_orm.posts.query()
return render_template(“blog.html”, posts=posts)
blog_blueprint.py
from blog_blueprint import blog_extension
your_app.py
def create_app(**config):
app = Flask(“myapp”)
...
app.register_blueprint(blog_extension)
return app

11. ●
●
Flask subclass
○ class MyOwnFlask(Flask):
pass
application factory
○ app = create_app(**config)
○ evitar import circular
●
Blueprints
○ Mesmo que seja uma one-page-app
●
Flask-Admin
○ Modular, insira qualquer view no admin, crud completo, actions, filters
●
Flask-Security
○ Login, Logout, Lembrar senha, Register, Access control, permissions
●
Flask-script
○ python manage.py faça_me_um_sanduiche
●
app.config_from_envvar
○ Settings desacoplado da app
○ export APP_SETTINGS=”/path/to/settings.cfg”
○ app.config_from_envvar(“APP_SETTINGS”)

12. and Google ?

13. http://bit.ly/flask-gae
# app.yaml
application : nome_do_app
version : 1
runtime : python27
api_version : 1
threadsafe: true
libraries:
- name: jinja2
version: "2.6"
- name: markupsafe
version: "0.15"
handlers:
- url: /static
static_dir : your_app_folder/static
- url: .*
script : main.app
# your_app.py
from flask import Flask
def create_app():
app = Flask(__name__)
return app
# main.py
from werkzeug import DebuggedApplication
from your_app import create_app
app = DebuggedApplication(create_app())

14. https://github.com/sashka/flask-googleauth
# your_app.py
from flask import Flask
from flask.ext.googleauth import GoogleFederated
from .configurator import register_views
def create_app():
app = Flask(__name__)
app.secret_key = “XYZ”
auth = GoogleFederated("dominio.com", app)
register_views(app, auth)
return app
# configurator.py
from .views import myview, …, ...
def register_views(app, auth)
secret = auth.required(myview)
app.add_url_rule(“/secret/”, view_func=secret)
…
...
# views.py
from flask import g
def myview()
return "Logged user, %s (%s)" % (g.user.name, g.user.email)
…
...

15. github.com/rochacbruno/Flask-GoogleMaps
pip install flask-googlemaps
from flask import Flask
from flask.ext.googlemaps import GoogleMaps
app = Flask(__name__)
GoogleMaps(app)
<div>
{{googlemap("my_awesome_map", 0.23234234, -0.234234234, markers=[(0.12, -0.45345), ...])}}
</div>

16. Thank you!
Bruno Rocha
http://brunorocha.org
bruno@rocha.com
http://github.com/rochacbruno
http://twitter.com.rochacbruno
http://pythonhub.com
www.quokkaproject.org