Jotted ideas on handling errors

Just jotted down some ideas about how to handle errors

Coding:

•  log the error and the calling parameters - use system console if log fails
•  close/clean-up any resources - don't forget to handle the case if they fail
•  notify the caller about the error
•  handle errors and not swallow them
• think for the edge cases - e.g do you handle 404/301/xxx for a POST ws-call that creates a new entity?

Architecture:

• check for errors in system test - what happens:
• if resource (dbase, network, file system, etc.) is not accessible
• if resource times-out
• if resource fails
• if resource is saturated (e.g disk full, JMS queue full, etc.)
• if a failed resource comes back online - is your system still consistent?
• if rollback or any recovery mechanism fails

         NOTE: the resource can be a 3rd party application or a library

• try to be robust - restart the failing module or stop using it
• think about the whole system and not the components for error testing
• think about the impossible - you might find some cases which are plausible