Purpose of this assignment

• Practice essential skills for your success in this course and in this field
  • Building an API for an existing service
  • Design a repeatable algorithm for validating the correct operation of your service
  • How to run a scalability test while validating correctness

Key References

• Here’s the description of the whole nT Test Interface
• Here’s the description of the nanoTwitter Scalability Testing Protocol

Assignment

• Write the code to support this new api
• Run a major loader.io test on your backend
• While it is running, issue a request to this validation api from your laptop
• Note the output

Deliverables

• Source code for your just the implementation of the required code zipped. (In other words just one or two source files.)
• Explanation of how the code will validate the correct behavior of the backend
• Log of the result of making the call to the api on your laptop

Comments, Context and Hints

• It is very easy to introduce bugs as you optimize your system to scale to large numbers
• Bugs that cause exceptions are easy to catch, they will show up in your logs
• Bugs that lead to incorrect results are more difficult to sense
• Types of bugs:
  • Some tweets of a followed user don’t show up on the follower’s timeline
  • Some tweets show up on the wrong other users timeline
  • Some tweets are lost altogether, e.g. they went into the cache but not the database
  • And more of similar types