From 22e9dd81c1f096c4928d770a7bc1f8f93a455936 Mon Sep 17 00:00:00 2001
From: wluyima <wyclif@openmrs.org>
Date: Mon, 1 Jul 2024 11:49:45 +0300
Subject: [PATCH] When a user logs out they should also be logged out of the
 authentication provider #12

Implemented post provider logout callback handler #12
---
 ftw/oidcauth/browser/configure.zcml |  7 +++++
 ftw/oidcauth/browser/oidc.py        | 49 +++++++++++++++++++++++++++++
 ftw/oidcauth/plugin.py              |  2 ++
 ftw/oidcauth/www/config.zpt         |  7 +++++
 4 files changed, 65 insertions(+)

diff --git a/ftw/oidcauth/browser/configure.zcml b/ftw/oidcauth/browser/configure.zcml
index 84d3a8a..8300fe7 100644
--- a/ftw/oidcauth/browser/configure.zcml
+++ b/ftw/oidcauth/browser/configure.zcml
@@ -11,4 +11,11 @@
     permission="zope.Public"
     />
 
+  <browser:page
+    for="plone.app.layout.navigation.interfaces.INavigationRoot"
+    name="logout"
+    class=".oidc.OIDCLogoutView"
+    permission="zope.Public"
+    layer="ftw.oidcauth.interfaces.IOIDCLayer"
+    />
 </configure>
diff --git a/ftw/oidcauth/browser/oidc.py b/ftw/oidcauth/browser/oidc.py
index 20600a2..e3162d5 100644
--- a/ftw/oidcauth/browser/oidc.py
+++ b/ftw/oidcauth/browser/oidc.py
@@ -1,7 +1,10 @@
+from Products.CMFPlone.browser.login.logout import LogoutView
 from Products.Five import BrowserView
 from ftw.oidcauth.browser.oidc_tools import OIDCClientAuthentication
 from ftw.oidcauth.errors import OIDCBaseError
+from six.moves.urllib.parse import parse_qsl, urlencode
 from zExceptions import NotFound as zNotFound
+from zope.component import getMultiAdapter
 from zope.interface import implements
 from zope.publisher.interfaces import IPublishTraverse
 from zope.publisher.interfaces import NotFound
@@ -23,6 +26,8 @@ def publishTraverse(self, request, name):
         if self.method is None:
             if name == 'callback':
                 self.method = name
+            elif name == 'logout':
+                self.method = name
             else:
                 raise NotFound(self, name, request)
         else:
@@ -32,6 +37,8 @@ def publishTraverse(self, request, name):
     def __call__(self):
         if self.method == 'callback':
             self.callback()
+        elif self.method == 'logout':
+            self.logout()
         else:
             raise zNotFound()
 
@@ -58,3 +65,45 @@ def set_error_response(self, status, message):
         response.setHeader('Content-Type', 'text/plain')
         response.setStatus(status, lock=1)
         response.setBody(message, lock=1)
+
+    def logout(self):
+        p = OIDCClientAuthentication.get_oidc_plugin()
+        base_url = get_base_url(self.context, self.request)
+        original_redirect = self.request.get('redirect')
+        redirect = base_url
+        if original_redirect:
+            if original_redirect.startswith("http:") or original_redirect.startswith("https:"):
+                redirect = original_redirect
+            else:
+                redirect = base_url + original_redirect
+
+        logout_base_url = p.end_session_endpoint
+        params = {}
+        if "?" in p.end_session_endpoint:
+            url_parts = p.end_session_endpoint.split("?")
+            logout_base_url = url_parts[0]
+            params.update(dict(parse_qsl(url_parts[1])))
+        params["client_id"] = p.client_id
+        params["post_logout_redirect_uri"] = redirect
+        logout_url = "{}?{}".format(logout_base_url, urlencode(params))
+        self.request.response.redirect(logout_url)
+
+
+class OIDCLogoutView(LogoutView):
+    def __call__(self):
+        if OIDCClientAuthentication.get_oidc_plugin().end_session_endpoint:
+            base_url = get_base_url(self.context, self.request)
+            next_ = self.request.get('next')
+            oidc_logout = base_url + '/oidc/logout'
+            if next_ is None or not next_.startswith(oidc_logout):
+                if next_:
+                    oidc_logout = "{}?{}".format(oidc_logout, urlencode({'redirect': next_}))
+                redirect = "{}?{}".format(base_url + '/logout', urlencode({'next': oidc_logout}))
+                self.request.response.redirect(redirect)
+                return
+
+        super(OIDCLogoutView, self).__call__()
+
+
+def get_base_url(context, request):
+    return getMultiAdapter((context, request), name="plone_portal_state").navigation_root_url()
diff --git a/ftw/oidcauth/plugin.py b/ftw/oidcauth/plugin.py
index b326733..55bf009 100644
--- a/ftw/oidcauth/plugin.py
+++ b/ftw/oidcauth/plugin.py
@@ -84,6 +84,7 @@ def __init__(self, id, title=None):
         self.token_endpoint = None
         self.user_endpoint = None
         self.jwks_endpoint = None
+        self.end_session_endpoint = None
         self._auto_provisioning_enabled = True
         self.properties_mapping = json.dumps({
             "userid": "sub",
@@ -228,6 +229,7 @@ def manage_updateConfig(self, REQUEST):
         self.token_endpoint = REQUEST.form.get('token-endpoint')
         self.user_endpoint = REQUEST.form.get('user-endpoint')
         self.jwks_endpoint = REQUEST.form.get('jwks-endpoint')
+        self.end_session_endpoint = REQUEST.form.get('end-session-endpoint')
         self._auto_provisioning_enabled = REQUEST.form.get('auto-provisioning-enabled')
 
         roles = REQUEST.form.get('roles')
diff --git a/ftw/oidcauth/www/config.zpt b/ftw/oidcauth/www/config.zpt
index c07461b..53b5890 100644
--- a/ftw/oidcauth/www/config.zpt
+++ b/ftw/oidcauth/www/config.zpt
@@ -81,6 +81,13 @@ Error: <b tal:content="options/error_message">
           <td><input type="text" name="jwks-endpoint" size="60"
                      tal:attributes="value context/jwks_endpoint"/></td>
         </tr>
+        <tr valign="top">
+          <td><div class="form-label">End Session Endpoint</div>
+          <div class="form-help"></div>
+          </td>
+          <td><input type="text" name="end-session-endpoint" size="60"
+                     tal:attributes="value context/end_session_endpoint"/></td>
+        </tr>
         <tr valign="top">
           <td><div class="form-label">Enable Auto Provisioning</div>
           <div class="form-help"></div>