Dynamically find the start and end pages of a textbook instead of hardcoding to 6.002 values

common/lib/xmodule/xmodule/course_module.py

@@ -21,7 +21,15 @@ class CourseDescriptor(SequenceDescriptor):
             self.title = title
             self.book_url = book_url
             self.table_of_contents = self._get_toc_from_s3()
+            self.start_page = int(self.table_of_contents[0].attrib['page'])
             
+            # The last page should be the last element in the table of contents,
+            # but it may be nested. So recurse all the way down the last element
+            last_el = self.table_of_contents[-1]
+            while last_el.getchildren():
+                last_el = last_el[-1]
+            
+            self.end_page = int(last_el.attrib['page'])
 
         @property
         def table_of_contents(self):

lms/djangoapps/staticbook/views.py

@@ -7,7 +7,7 @@ from courseware.courses import get_course_with_access
 from lxml import etree
 
 @login_required
-def index(request, course_id, book_index, page=0):
+def index(request, course_id, book_index, page=None):
     course = get_course_with_access(request.user, course_id, 'load')
     staff_access = has_access(request.user, course, 'staff')
 
@@ -15,10 +15,15 @@ def index(request, course_id, book_index, page=0):
     textbook = course.textbooks[book_index]
     table_of_contents = textbook.table_of_contents
 
+    if page is None:
+        page = textbook.start_page
+
     return render_to_response('staticbook.html',
                               {'book_index': book_index, 'page': int(page),
                                'course': course, 'book_url': textbook.book_url,
                                'table_of_contents': table_of_contents,
+                               'start_page' : textbook.start_page,
+                               'end_page' : textbook.end_page,
                                'staff_access': staff_access})
 
 def index_shifted(request, course_id, page):

lms/templates/staticbook.html

@@ -38,14 +38,14 @@ function goto_page(n) {
 
 function prev_page() {
   var newpage=page-1;
-  if(newpage<0) newpage=0;
+  if(newpage< ${start_page}) newpage=${start_page};
   goto_page(newpage);
   log_event("book", {"type":"prevpage","new":page});
 }
 
 function next_page() {
   var newpage=page+1;
-  if(newpage>1008) newpage=1008;
+  if(newpage> ${end_page}) newpage=${end_page};
   goto_page(newpage);
   log_event("book", {"type":"nextpage","new":page});
 }