Forums Braindump from Greg

History

• In the beginning, there was Asbot for the first version of 6.002x.
• When we made a site for multiple courses, we discovered that Asbot didn't support multiple courses with different discussion forums well.
• Amondo Fox from Berkeley decided to write something.
• So originally written by a team (grad student and undergrads) at Berkeley.
• They set up the original architecture, which we still have.

Comments Service (basically a data store from the LMS perspective)

• written in Ruby
• data store in Mongo
• text search in Elastic Search
• all updates need to update both Mongo and Elastic Search

LMS

• originally written by Dave to provide a higher-level interface
• lms/lib/comment_client
  • handles all communication to comment service
• lms/djangoapps/django_comment_client
  • provides the django views
• common/djangoapps/django_comment_common
  • shared between studio and lms
    • studio uses it to seed the roles table when a course is created
  • has role and permission data
  • stored in RDS (mySQL) in its own tables
  • table of very granular permissions
    • e.g., open/close thread
  • in practice, only (really) 2 roles with 2 permissions each
    • Student
    • Privileged User
      • Administrators
      • Moderators
        • originally, all permissions, except grant/revoke moderator role
        • but, these roles are managed in instructor dashboard so no need for separation between Moderator and Administrator
      • Community TAs
        • same as moderator role, except surfaced role name is different when displayed on a thread
• LMS uploads images to S3

Browser

• UX designers: Marco and then Brian

June 2013 -> Aug 2014

• Forums team was formed: Greg, Jim, and Kevin (a contractor just for a few months).
• Forums performance improvement: 5 second timeout between LMS and Comments Service happening for over 1% of the requests.
  • Heroku is not great for scaling.
  • Introduction threads didn't perform well.  They would get 1000-2000 comments for just saying "Hi!"
    • supported them with infinite scroll rather than paging
• UX issues: front-end wouldn't tell you if there was an error.  The UI would just continue to spin.  There are still some front-end deficiencies there.

Discussion Content

• Markdown
  • We use an open-source markdown editing tool.
  • markdown format stored
• White-list of HTML tags
  • honored on the browser-side when rendering the content
  • possible to store non-white-listed tags if hackre circumvents browser, but the browser on the reader's end will filter out those tags
• Mathjax
  • math formula renderer implemented in JS on the client-side

Future

• Brian worked on designs to fix the navigation experience.

• Need to improve search UX.