flask-simplelogin 0.0.0

Flask Simple Login - Login Extension for Flask

There are good and recommended options to deal with web authentication in Flask.

I recommend you use:

• Flask-Login

• Flask-Security

Those extensions are really complete and production ready!

So why Flask Simple Login?

However sometimes you need something simple for that small project or for prototyping.

Flask Simple Login

What it provides:

• Login and Logout forms and pages

• Function to check if user is logged-in

• Decorator for views

• Easy and customizable login_checker

What it does not provide: (but of course you can easily implement by your own)

• [STRIKEOUT:Database Integration]

• [STRIKEOUT:Password management]

• [STRIKEOUT:API authentication]

• [STRIKEOUT:Role or user based access control]

Hot it works

pip install flask_simplelogin

from flask import Flask
from flask_simplelogin import SimpleLogin

app = Flask(__name__)
SimpleLogin(app)

That’s it! now you have /login and /logout routes in your application.

The username defaults to admin and the password defaults to secret (yeah that’s not clever, let’s see how to change it)

Configuring

from flask import Flask
from flask_simplelogin import SimpleLogin

app = Flask(__name__)
app.config['SECRET_KEY'] = 'something-secret'
# TIP: use `dynaconf` to configure your Flask app and those values will be taken from environment variables.


def auth_my_user(user):
    "user = {'username': 'foo', 'password': 'bar'}"
    # do the authentication here, it is up to you!
    # query your database, check your user/passwd file
    # connect to external service.. anything.
    return True or False  # True = authenticated


SimpleLogin(app, login_checker=auth_my_user)

Checking if user is logged in

from flask_simplelogin import is_logged_in

if is_logged_in():
    # do things if anyone is logged in

if is_logged_in('admin'):
    # do things only if admin is logged in

Decorating your views

from flask_simplelogin import login_required

@app.route('/it_is_protected')
@login_required   # < --- simple decorator
def foo():
    return 'secret'

Protecting Flask Admin views

from flask_admin.contrib.foo import ModelView
from flask_simplelogin import is_logged_in


class AdminView(ModelView)
    def is_accessible(self):
        return is_logged_in('admin')

Customizing templates

There are only one template to customize and it is called login.html

Example is:

{% extends 'base.html' %}
{% block title %}Login{% endblock %}
{% block messages %}
   {{super()}}
   {%if form.errors %}
     <ul class="alert alert-danger">
       {% for field, errors in form.errors.items() %}
         <li>{{field}} {% for error in errors %}{{ error }}{% endfor %}</li>
       {% endfor %}
     </ul>
   {% endif %}
{% endblock %}

{% block page_body %}
       <form action="{{ url_for('simplelogin.login', next=request.args.get('next', '/')) }}" method="post">
            <div class="form-group">
            {{ form.csrf_token }}
            {{form.username.label}}<div class="form-control">{{ form.username }}</div><br>
            {{form.password.label}}<div class="form-control"> {{ form.password }}</div><br>
            </form>
           <input type="submit" value="Send">
       </form>
{% endblock %}

Take a look at the examples app in this repository.

And you can customize it in anyway you want and need, it receives a form in context and it is a WTF form the submit should be done to request.path which is the same /login view.

You can also use {% if is_logged_in %} in your template if needed.

Requirements

• Flask-WTF and WTForms

• having a SECRET_KEY set in your app.config