Python web

webapp2

import webapp2

class HelloWorld(webapp2.RequestHandler):
	def get(self):
		self.response.write('Hello Udacity CS253!')
	def post(self):
		nom=self.request.get('nom')
		ip=self.request.remote_addr
		self.response.write('Hello %s' % nom)

app = webapp2.WSGIApplication([
	('/hello', HelloWorld),
	('/', birthday.MainPage),
	('/thanks', birthday.ThanksHandler)]
	,debug=True)

Méthodes

redirect(page): si pb Unicode utiliser str(url)

Templates jinja2

Semble complexe mais il suffit de copier coller!

Mise en place

Ajouter à libraries: dans app.yaml

- name: jinja2
  version: latest

Dans main.py

import jinja2
import os

template_dir = os.path.join(os.path.dirname(__file__), 'templates')
jinja_env = jinja2.Environment(loader = jinja2.FileSystemLoader(template_dir),
							   autoescape = True)

def render_str(template, **params):
	t = jinja_env.get_template(template)
	return t.render(params)

class BaseHandler(webapp2.RequestHandler):
	def write(self, *a, **kw):
		self.response.out.write(*a, **kw)
	def render(self, template, **kw):
		self.write(render_str(template, **kw))

template

Utilisation: Les fichiers html template incluent les variables sous la forme {{var}}. On peut aussi inclure du code python sous la forme: {% code %} Exemple de template:

{% for art in arts %} 
<div class="art">
	<div class="art-title">{{art.title}}</div>
	<pre class="art-body">{{art.art}}</pre>
</div>
{% endfor %}

Autre exemple de template:

{% if img_url %} 
<img src={{img_url}}>
{% endif %}

Héritage

Dans le fichier base.html (template HTML de base) insérer:

{% block content %}{% endblock %}

Dans les fichiers HTML dérivés insérer:

{% extends "base.html" %}
{% block content %}

Mon contenu...

{% endblock %}

Appel

def render_front(self, title="", art="", error=""):
	arts = db.GqlQuery("SELECT * FROM Art ORDER BY created DESC")
	self.render("front.html", title=title, art=art, error = error, arts = arts)

SQLite

import sqlite3

db = sqlite3.connect(':memory:') #base en RAM

db.execute('create table links ' +
		  '(id integer, submitter_id integer, submitted_time integer, ' +
		  'votes integer, title text, url text)')

for link in links:
	db.execute('insert into links values (?, ?, ?, ?, ?, ?)', link)

def query():
	c = db.execute("select * from links") #curseur
	results=c.fetchall()
	#print results
	for link_tuple in c:
		link = Link(*link_tuple) # *=passer tous les arguments
		print link.votes

def query2():
	c = db.execute("SELECT * FROM LINKS WHERE ID=2")
	link = c.fetchone() #tuplé
	nbVotes=link[3]

appengine db

from google.appengine.ext import db

class Art(db.Model):
	title = db.StringProperty(required = True)
	art = db.TextProperty(required = True)
	created = db.DateTimeProperty(auto_now_add = True)
	modified = db.DateTimeProperty(auto_now = True)
	#autres types: Integer, Float, Date.


if title and art:
	a = Art(title = title, art = art)
	a.put() #INSERT


arts = db.GqlQuery("SELECT * FROM Art ORDER BY created DESC")

Utilisation des clés

def add(title,content):
	post = Post(title = title, content = content)
	post.put() #INSERT
	return post.key().id()

def getPost(p_id):
	p_id=int(p_id)
	key = db.Key.from_path('Post', int(p_id)) #Premier argument: l'entité
	post = db.get(key)
	return post

urllib ou urllib2

import urllib2
p=urllib2.urlopen('http://www.example.com/')
pageHTML=p.read()
print p.getcode() #200 ou 404 par exemple
print p.headers['content-type']
print p.headers['server']

print urllib.urlencode(dictionnaire)
>> nom=toto&valeur=12