ServiceInterfaces

What Makes A Good Service Interface?

• Follow REST in terms of Create/Read/Update/Delete separation
  • POST: Create
  • GET: Retrieve
  • PUT: Update/change
  • DELETE: Delete/remove
• Need to think hard about how data will evolve
  • Identify abstractions that will shift (trade data) and decide how you'll deal with that
  • In general, data format ownership should be federated - placed with the relevant expert teams
  • URL structure is worth very careful thought
• For return data
  • Give a choice of XML or JSON
  • Preserve full exception information - ensure the format supports this
• Design guidelines
  • Be consistent - if a concept appears more than once, ensure it's expressed the same way in each place
  • Be stateless (this is simpler and more scalable)
  • Don't make the operations too granular - remember call overhead
  • Be testable - if you can't validate, you can't evolve or change the system