From fee3b622eef1a137ecc3f939763f288a01185a49 Mon Sep 17 00:00:00 2001
From: Piotr Dobrowolski <admin@tastycode.pl>
Date: Tue, 10 Oct 2017 23:06:27 +0200
Subject: [PATCH] Initial commit

---
 .gitignore            |  1 +
 spaceauth/__init__.py | 94 +++++++++++++++++++++++++++++++++++++++++++
 spaceauth/caps.py     | 52 ++++++++++++++++++++++++
 3 files changed, 147 insertions(+)
 create mode 100644 .gitignore
 create mode 100644 spaceauth/__init__.py
 create mode 100644 spaceauth/caps.py

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..539da74
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+*.py[co]
diff --git a/spaceauth/__init__.py b/spaceauth/__init__.py
new file mode 100644
index 0000000..459e668
--- /dev/null
+++ b/spaceauth/__init__.py
@@ -0,0 +1,94 @@
+from flask import Blueprint, request, url_for, session, redirect, abort, flash
+from flask_oauthlib.client import OAuth, OAuthException
+from flask_login import LoginManager, login_user, logout_user, current_user, login_required, UserMixin
+from spaceauth.caps import cap_required
+
+
+class SpaceAuth(object):
+    def __init__(self, app=None, *args, **kwargs):
+        self.oauth = OAuth()
+        self.remote = self.oauth.remote_app(
+            'spaceauth',
+            base_url='https://sso.hackerspace.pl/api/',
+            access_token_url='https://sso.hackerspace.pl/oauth/token',
+            authorize_url='https://sso.hackerspace.pl/oauth/authorize',
+            request_token_params={'scope': 'profile:read'},
+            app_key='SPACEAUTH')
+        self.remote.tokengetter(self.tokengetter)
+
+        bp = Blueprint('spaceauth', __name__)
+        bp.add_url_rule('/login', 'login', self.login_view)
+        bp.add_url_rule('/logout', 'logout', self.logout_view)
+        bp.add_url_rule('/callback', 'callback', self.callback_view)
+        self.blueprint = bp
+
+        self.login_manager = LoginManager()
+        self.login_manager.refresh_view = 'spaceauth.login'
+        self.login_manager.login_view = 'spaceauth.login'
+        self.login_manager.user_loader(self.user_loader_handler)
+
+        if app:
+            self.init_app(app, *args, **kwargs)
+
+    def init_app(self, app, url_prefix='/oauth'):
+        self.oauth.init_app(app)
+        self.login_manager.init_app(app)
+        app.register_blueprint(self.blueprint, url_prefix=url_prefix)
+
+        @app.errorhandler(OAuthException)
+        def errorhandler(err):
+            flash('OAuth error occured', 'error')
+            return redirect('/')
+
+    def login_view(self):
+        session['spaceauth_next'] = request.args.get('next') or request.referrer
+        return self.remote.authorize(
+            callback=url_for('spaceauth.callback', _external=True)
+            )
+
+    def logout_view(self):
+        # TODO revoke token
+        session.pop('spaceauth_token', None)
+        session.pop('spaceauth_next', None)
+        logout_user()
+        return redirect('/')
+
+    def callback_view(self):
+        resp = self.remote.authorized_response()
+        if resp is None:
+            raise OAuthException(
+                'Access denied', type=request.args.get('error'))
+
+        # TODO encrypt token...?
+        session['spaceauth_token'] = resp['access_token']
+        profile = self.remote.get('profile').data
+
+        login_user(self.user_loader_handler(profile['username'], profile))
+        return redirect(session.pop('spaceauth_next', None) or '/')
+
+    def tokengetter(self):
+        return (session.get('spaceauth_token'), '')
+
+    def user_loader_handler(self, uid, profile=None):
+        """
+        Default user loader just to differentiate authenticated user from
+        anonymous.
+        """
+
+        user = UserMixin()
+        user.id = uid
+        return user
+
+    def user_loader(self, func):
+        """
+        Define flask_login-like user loader. Application is supposed to create
+        its user model when missing. Additional `profile` argument is passed
+        with user profile information right after login.
+        """
+
+        self.user_loader_handler = func
+        self.login_manager.user_loader(self.user_loader_handler)
+        return func
+
+    def user_profile(self):
+        return self.remote.get('profile').data
diff --git a/spaceauth/caps.py b/spaceauth/caps.py
new file mode 100644
index 0000000..a82eb23
--- /dev/null
+++ b/spaceauth/caps.py
@@ -0,0 +1,52 @@
+from flask import abort, session, current_app
+from flask_login import current_user
+from flask_login.signals import user_logged_out
+import requests
+import functools
+import time
+
+
+def cap_check(capability, user=None):
+    if not current_user.is_authenticated:
+        return False
+
+    user = user or current_user.get_id()
+
+    cache_key = '{}-{}'.format(user, capability)
+    cached_cap = session.get('_caps', {}).get(cache_key, (False, 0))
+
+    if cached_cap[1] > time.time():
+        return cached_cap[0]
+
+    allowed = requests.get(
+        'https://capacifier.hackerspace.pl/%s/%s' % (capability, user)
+        ).status_code == 200
+
+    if '_caps' not in session:
+        session['_caps'] = {}
+
+    session['_caps'][cache_key] = \
+        (allowed, time.time() + current_app.config.get('CAP_TTL', 3600))
+
+    return allowed
+
+
+@user_logged_out.connect
+def caps_cleanup(app, user):
+    # Cleanup caps cache
+    session.pop('_caps', None)
+
+
+def cap_required(capability):
+    '''Checks if user has desired capacifier capability'''
+
+    def inner(func):
+        @functools.wraps(func)
+        def wrapped(*args, **kwargs):
+            if not cap_check(capability):
+                abort(403)
+
+            return func(*args, **kwargs)
+
+        return wrapped
+    return inner