THE SYMFONY OF THE FLASK

@allucardster

Acerca de mi

  • Ingeniero de Sistemas
  • +6 años de experiencia
  • FrontEnd, Backend
  • Streamlinesocial
  • Co-fundador de SUDO

Qué es Symfony?

"Es un framework para el desarrollo de aplicaciones web basado en el patrón Modelo Vista Controlador"

Acerca del Framework

  • Creado por Fabien Potencier
  • Fácil de instalar y configurar
  • Potente Cliente de comandos
  • Ampliamente documentado
  • Adaptable
  • Sigue las mejores practicas
    de desarrollo
  • PEAR
  • PHP templates
  • Propel - Doctrine
  • Aplicaciones y Módulos
  • Composer
  • Twig
  • Doctrine2
  • Bundles (paquetes)

Comunidad

ZONA DE CONFORT

Conceptos y Componentes

  • Bundles
  • Anotaciones
  • Configuración
  • CLI/comandos
  • Routing
  • ORM
  • Motor de plantillas
  • Formularios y Validaciones

Que es Flask?

"Es un microframework para el desarrollo de aplicaciones web escrito en Python"

Acerca del framework

  • Creado por Armin Ronacher
  • Inspirado en Sinatra
  • Fácil de instalar y configurar
  • Excelente Documentación
  • Open source

WERKZEUG

Jinja2

Extensiones

  • Garantiza que el núcleo
    sea simple
  • Permite agregar y reemplazar
    funcionalidades completas

Que necesitamos?

  • Python 2.7.9
  • virtualenv
  • virtualenvwrapper

Como instalar?

:~ mkvirtualenv env
(env):~ pip install Flask

Hello World

# helloworld.py

# Importar Flask
from flask import Flask

# Se crea la aplicacion
app = Flask(__name__)

# Se define una ruta para la funcion "helloWorld"
@app.route("/")
def helloWorld():
    return '<h1>Hello World!</h1>'

# Ejecutar la aplicacion en http://0.0.0.0:5000
if __name__ == '__main__':
    app.run(host='0.0.0.0', port=5000)
(env):~ python helloworld.py
 * Running on http://0.0.0.0:5000/ (Press CTRL+C to quit)

Flask-Script

# manage.py

from flask.ext.script import Manager

from myapp import app

manager = Manager(app)

@manager.command
def hello():
    print "hello"

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

Configuración

# Basic Config
app = Flask(__name__)
app.config['DEBUG'] = True

# Read and write
debug = app.debug
app.debug = True

Configuración

class BaseConfig(object):
    TESTING = False
    DEBUG = False

class DevConfig(BaseConfig):
    DEBUG = True
    TESTING = True

class TestConfig(BaseConfig):
    DEBUG = False
    TESTING = True

app.config.from_object('DevConfig')
app.config.from_pyfile('path/to/app.cfg', silent=True)

# app.cfg file
DEBUG = False
SERVER_HOST='0.0.0.0'

Routing

@app.route('/')
def index():
    return 'Index Page'

@app.route('/hello')
def hello():
    return 'Hello World'

@app.route('/user/<username>')
def show_user_profile(username):
    return 'User %s' % username

@app.route('/post/<int:post_id>')
def show_post(post_id):
    return 'Post %d' % post_id

@app.route('/login', methods=['GET', 'POST'])
def login():
    if request.method == 'POST':
        do_the_login()
    else:
        show_the_login_form()

Flask-Sqlalchemy

from flask import Flask
from flask_sqlalchemy import SQLAlchemy

app = Flask(__name__)
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:////tmp/test.db'
db = SQLAlchemy(app)


class User(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    username = db.Column(db.String(80), unique=True)
    email = db.Column(db.String(120), unique=True)

    def __init__(self, username, email):
        self.username = username
        self.email = email

Jinja2

<!-- Variables -->
{% set foo = 'bar' %}
{% set foo = [1, 2] %}
{% set foo = {'foo': 'bar'} %}

<!-- Strings -->
{{ "Hello World" }} {{ 'It\'s good' }}

<!-- Integers - Floats -->
{{ 42 }} {{ 42.5 }}

<!-- Arrays -->
["foo", "bar", 42, 42.5]

<!-- Hashes -->
{ 'foo': 'foo', 'bar': 'bar' }

<!-- Others -->
{% set foo = True %}
{% set foo = False %}
<!-- If/Else -->
{% if kenny.sick %}
    Kenny is sick.
{% elseif kenny.dead %}
    You killed Kenny! You bastard!!!
{% else %}
    Kenny looks okay --- so far
{% endif %}

<!-- Loop variables -->
{% for user in users %}
    {{ loop.index }} - {{ user.username }}
{% endfor %}

{# note: commented-out template because we no longer use this
    {% for user in users %}
        ...
    {% endfor %}
#}

Jinja2

# layout.html
<!doctype html>
<title>Flaskr</title>
<link rel=stylesheet type=text/css href="{{ url_for('static', filename='style.css') }}">
<div class=page>
  <h1>Flaskr</h1>
  {% block body %}{% endblock %}
</div>
{% extends "layout.html" %}
{% block body %}
<p>
    Lorem ipsum dolor sit amet, consectetur adipiscing elit.
</p>
{% endblock %}

Flask-WTForms

from flask_wtf import Form
from wtforms import StringField
from wtforms.validators import DataRequired, Length

class MyForm(Form):
    username = StringField('Username', validators=[DataRequired(), Length(max=255)])
    first_name = StringField('First name', [Length(max=255)])
    last_name = StringField('Last name', [Length(max=255)])
    zip_code = StringField('Zip code', [Length(max=12)])

Flask-WTForms

{% macro render_field(field) %}
  <dt>{{ field.label }}
  <dd>{{ field(**kwargs)|safe }}
  {% if field.errors %}
    <ul class=errors>
    {% for error in field.errors %}
      <li>{{ error }}</li>
    {% endfor %}
    </ul>
  {% endif %}
  </dd>
{% endmacro %}

<form method=post action="/register">
  <dl>
    {{ render_field(form.username) }}
    {{ render_field(form.email) }}
    {{ render_field(form.password) }}
    {{ render_field(form.confirm) }}
    {{ render_field(form.accept_tos) }}
  </dl>
  <p><input type=submit value=Register>
</form>

Preguntas?

Muchas Gracias

The Symfony of the Flask

By Richard Andres Melo Carrillo

Made with Slides.com

The Symfony of the Flask

Una breve introduccion a Flask desde la vision de un Symfony Developer. @calidevco, http://calidev.co

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