Sign the requests going from the XBlock to the SY server

schoolyourself/schoolyourself.py

 """The base class for School Yourself XBlocks (lessons and reviews)."""
 
+import hmac
 import os
 import pkg_resources
 
@@ -103,16 +104,22 @@ class SchoolYourselfXBlock(XBlock):
       return template.render_unicode(**context)
 
 
-    def get_partner_url_params(self):
+    def get_partner_url_params(self, shared_key=None):
       """A helper method that generates a dict of URL params that we can
       append to the end of a URL, containing the partner ID and the
       user's anonymouse user ID. These are typically transmitted as URL
-      params. in the iframes."""
-      url_params = {"id": self.module_id,
-                    "partner": "edx"}
+      params. in the iframes.
+
+      If a shared_key is provided and there is a username to encode,
+      we will sign it with the shared key.
+      """
+      url_params = {"partner": "edx"}
       user_id = self.get_student_id()
       if user_id:
         url_params["partner_user_id"] = user_id
+        if shared_key:
+          url_params["partner_signature"] = hmac.new(str(shared_key),
+                                                     user_id).hexdigest()
 
       return url_params
 

schoolyourself/schoolyourself_lesson.py

@@ -24,7 +24,8 @@ class SchoolYourselfLessonXBlock(SchoolYourselfXBlock):
       """
       # Construct the URL we're going to stuff into the iframe once
       # it gets launched:
-      url_params = self.get_partner_url_params()
+      url_params = self.get_partner_url_params(self.shared_key)
+      url_params["id"] = self.module_id
 
       # Set up the screenshot URL:
       screenshot_url = "%s/page/screenshot/%s" % (self.base_url,

schoolyourself/schoolyourself_review.py

@@ -28,7 +28,8 @@ class SchoolYourselfReviewXBlock(SchoolYourselfXBlock):
       """
       # Construct the URL we're going to stuff into the iframe once
       # it gets launched:
-      url_params = self.get_partner_url_params()
+      url_params = self.get_partner_url_params(self.shared_key)
+      url_params["module"] = self.module_id
 
       # Set up the screenshot URL:
       screenshot_url = "%s/page/screenshot/%s" % (self.base_url,
@@ -73,7 +74,8 @@ class SchoolYourselfReviewXBlock(SchoolYourselfXBlock):
          """\
             <vertical_demo>
               <schoolyourself_review
-                  module_id="geometry/lines_rays"
+                  module_id="algebra/multiplication"
+                  shared_key="test"
               />
             </vertical_demo>
          """),