Application-scope variables in Flask?

Question

Is there such thing as application-scope python variables in Flask? I'd like to implement some primitive messaging between users, and shared data cache. Of course, it is possible to implement this via a database, but I wanted to know maybe there is a db-free and perhaps faster approach. Ideally, if the shared variable would be a live python object, but my needs would be satisfied with strings and ints, too.

Edit: complemented with (non-working) example

from flask import g

@app.route('/store/<name>')
def view_hello(name=None):
    g.name = name
    return "Storing " + g.name

@app.route("/retrieve")
def view_listen():
    n = g.name
    return "Retrieved: " + n

At trying to retrieve g.name, this triggers error: AttributeError: '_RequestGlobals' object has no attribute 'name'

Answer 1

I'm unsure whether this is a good idea or not, but I've been using this to share data easily between requests:

class MyServer(Flask):

    def __init__(self, *args, **kwargs):
            super(MyServer, self).__init__(*args, **kwargs)

            #instanciate your variables here
            self.messages = []

app = MyServer(__name__)

@app.route("/")
def foo():
    app.messages.append("message")