83 lines
2.0 KiB
Markdown
83 lines
2.0 KiB
Markdown
---
|
|
title: Flask Day 2
|
|
date: 2016-02-16 22:45:06
|
|
tags:
|
|
- flask
|
|
---
|
|
|
|
To handle web forms we use [Flask-WTF ](http://packages.python.org/Flask-WTF). So we need to write a config file (file `config.py`):
|
|
|
|
``` python
|
|
WTF_CSRF_ENABLED = True
|
|
SECRET_KEY = 'you-will-never-guess'
|
|
```
|
|
|
|
And then you need to use this config (file `app/__init__.py`):
|
|
|
|
``` python
|
|
from flask import Flask
|
|
|
|
app = Flask(__name__)
|
|
app.config.from_object('config')
|
|
|
|
from app import views
|
|
```
|
|
|
|
Let's build a simple form (file `app/forms.app`):
|
|
|
|
``` python
|
|
from flask.ext.wtf import Form
|
|
from wtforms import StringField, BooleanField
|
|
from wtforms.validators import DataRequired
|
|
|
|
class LoginForm(Form):
|
|
openid = StringField('openid', validators=[DataRequired()])
|
|
remember_me = BooleanField('remember_me', default=False)
|
|
```
|
|
|
|
The `DataRequired()` is a validator that checks the field is empty or not.
|
|
|
|
After that, we need a HTML page to show the form (file `app/templates/login.html`):
|
|
|
|
``` html
|
|
<!-- extend from base layout -->
|
|
{% extends "base.html" %}
|
|
|
|
{% block content %}
|
|
<h1>Sign In</h1>
|
|
<form action="" method="post" name="login">
|
|
{{ form.hidden_tag() }}
|
|
<p>
|
|
Please enter your OpenID:<br>
|
|
{{ form.openid(size=80) }}<br>
|
|
</p>
|
|
<p>{{ form.remember_me }} Remember Me</p>
|
|
<p><input type="submit" value="Sign In"></p>
|
|
</form>
|
|
{% endblock %}
|
|
```
|
|
|
|
|
|
|
|
The final step is to code a view function that renders the template and receiving data from form (file `app/views.py`):
|
|
|
|
``` python
|
|
from flask import render_template, flash, redirect
|
|
from app import app
|
|
from .forms import LoginForm
|
|
|
|
# index view function suppressed for brevity
|
|
|
|
app.route('/login', methods=['GET', 'POST'])
|
|
def login():
|
|
form = LoginForm()
|
|
if form.validate_on_submit():
|
|
flash('Login requested for OpenID="%s", remember_me=%s' %
|
|
(form.openid.data, str(form.remember_me.data)))
|
|
return redirect('/index')
|
|
return render_template('login.html',
|
|
title='Sign In',
|
|
form=form)
|
|
```
|
|
|