The document discusses the integration of Drupal as a central content management system with various other platforms including Moodle, Salesforce, and Amazon Web Services to create a comprehensive learning environment. It highlights the advantages of Drupal, particularly its flexibility, user management capabilities, and support for web services and APIs. The author emphasizes the benefits of batch processing over real-time processing for efficiency and ease of debugging in system communication.

1. Presented by James Purser // 06-03-2015
Drupal – At the centre of the
web

2. In the beginning...
There was Drupal and it was good

3. Drupal provides all...
A Framework
• Flexible content management system
• Core set of libraries
• User management
• Comprehensive API
• Large third party module set

4. Sometimes Drupal needs to play with
others...

5. The horde... (but shhh the users don’t
know)
We built a Learning Platform out of different moving parts
• CMS (Drupal) - For content
• LMS (Moodle) - Learning Materials
• Student Management System - Student and course
metadata
• Payment Gateways (x2) - e-commerce functionality
• CRM (Salesforce) - Lead management
• Identity Provider (SAML)
• Amazon Web Services - Queues and Mail services

6. The spider at the heart of the web...

7. Why Drupal?
Because of these bits
• Core set of libraries
• User management
• Comprehensive API
• Large third party module set
• Flexible content management system

8. Why Drupal?
And these things:
• Webservices support out of the box
• hooks - ie: module_user_save allows us to ensure that all
systems are updated when a user is updated in drupal.
• PHP is a mature and flexible language and library set.
• Drush is incredibly useful not only for development but
bespoke cli and devops
• Drupal framework features make developing new
functionality easier

9. A Real Time Comms Story...
Creating a User (as part of module_user_save):
• New user registers with Drupal
• Drupal then does the following via real time webservices
– Register the new user with the LMS
– Register the new user with the Student Management System
– Register the new user with the CRM
– Updates its own user information with identifiers from each of
the above.

10. Queueing for an Invoice...
Generating an invoice after enrollment:
• User decides to enrol, goes through e-commerce process
• If all good (as in they have the money)
– Student Management System completes enrollment with LMS
– Then puts a message onto a payment queue for Drupal to
process on a schedule
– Drupal (via cron) pops the message, processes information
and emails invoice to new student.

11. Which would you pick?
– Do you need to process in real time or can you wear a delay?
– How much information are you trying to process at one time?
– What resources do you have available (CPU, RAM etc)?
– How will the service affect your applications operation?
– What is your tolerance failure?
– What data governance requirements do you have?
– What are you comfortable with?

12. Webservice vs Queue deathmatch...
Webservices
• Real time
• Part of the page build
• Widely supported
• Multiple Protocols
• Heavy on the resources
• Load spikes can be
dangerous
• Not failure tolerant
• Potential attack vector
• A bit fiddly to test
Queues
• Delayed processing on a
schedule
• Light weight
• Queue’s are more highly
available than webservices
• They buffer comms between
system components
• More tolerant to outages and
peak load issues

13. Monitoring your Integration Hub...
• Having so many different system can make keeping track of the
state of things difficult
• With Drupal as our hub, we can leverage that to build a series of
webservices that allow remote monitoring services to keep a
close eye on the health of the system
• Each check is an independent webservice/function. The response
object is JSON

14. Some lessons learnt...

15. Where possible go batch...
• The problem with realtime is that if one part of the process goes
down then everything goes down
• Batch processing allows you to schedule how and when you
process the requests, much better management of resources
• Debugging is easier (trying to catch a live webservice call vs
checking a packet on a queue)

16. About Catalyst

17. Catalyst Clients

18. Open Source Technologies