Merge pull request #60 from Harvard-University-iCommons/task/thornton…

…/tlt-3542/fix_tool_config_launch_url

TLT-3591 resource_link_id in tool config

canvas_manage_course/settings/base.py

@@ -13,10 +13,7 @@
 # Build paths inside the project like this: os.path.join(BASE_DIR, ...)
 import logging
 import os
-import warnings
 
-# Need to import patch_reverse here to override the loading order of Django's reverse function.
-from django_auth_lti import patch_reverse
 from django.core.urlresolvers import reverse_lazy
 
 from .secure import SECURE_SETTINGS
@@ -52,7 +49,7 @@
     'manage_sections',
 ]
 
-MIDDLEWARE = [
+MIDDLEWARE_CLASSES = [
     'django.contrib.sessions.middleware.SessionMiddleware',
     'django.middleware.common.CommonMiddleware',
     'cached_auth.Middleware',

canvas_manage_course/views.py

@@ -1,27 +1,30 @@
 # -*- coding: utf-8 -*-
 
 import logging
+import urllib
+import urlparse
 
 from django.contrib.auth.decorators import login_required
+from django.core.urlresolvers import reverse
 from django.http import HttpResponse
 from django.shortcuts import redirect, render
-from django.core.urlresolvers import reverse
 from django.views.decorators.csrf import csrf_exempt
 from django.views.decorators.http import require_http_methods
 from ims_lti_py.tool_config import ToolConfig
-
-from isites_migration.utils import get_previous_isites
 from lti_school_permissions.decorators import (
     lti_permission_required,
     lti_permission_required_check)
 
+from isites_migration.utils import get_previous_isites
+
 logger = logging.getLogger(__name__)
 
 
 @require_http_methods(['GET'])
 def tool_config(request):
 
-    url = "https://{}{}".format(request.get_host(), reverse('lti_launch', exclude_resource_link_id=True))
+    url = "https://{}{}".format(request.get_host(), reverse('lti_launch'))
+    url = _url(url)
 
     title = 'Manage Course'
     lti_tool_config = ToolConfig(
@@ -46,6 +49,26 @@ def tool_config(request):
     return HttpResponse(lti_tool_config.to_xml(), content_type='text/xml')
 
 
+def _url(url):
+    """
+    *** Taken from ATG's django-app-lti repo to fix the issue of resource_link_id being included in the launch url
+    *** TLT-3591
+    Returns the URL with the resource_link_id parameter removed from the URL, which
+    may have been automatically added by the reverse() method. The reverse() method is
+    patched by django-auth-lti in applications using the MultiLTI middleware. Since
+    some applications may not be using the patched version of reverse(), we must parse the
+    URL manually and remove the resource_link_id parameter if present. This will
+    prevent any issues upon redirect from the launch.
+    """
+    parts = urlparse.urlparse(url)
+    query_dict = urlparse.parse_qs(parts.query)
+    if 'resource_link_id' in query_dict:
+        query_dict.pop('resource_link_id', None)
+    new_parts = list(parts)
+    new_parts[4] = urllib.urlencode(query_dict)
+    return urlparse.urlunparse(new_parts)
+
+
 @login_required
 @require_http_methods(['POST'])
 @csrf_exempt