producing robust programs

producing robust programs

1. defensive design

2. protection against unexpected user inputs

3. maintability

   • maintaining that the code will last a long time
   • reduces the chance of a mistake

4. minimising/removing bugs

5. validation

   • defensive strategies
   • sensible and reasonable
   • type check length check
     • format check range check presence check

6. formatting means subroutines

7. naming conventions creates constants

8. testing

   • iterative
     • repeatedly test the program while making it
   • final
     • do the testing when the program is finished
   • testing if the program functions as it was designed

9. test table

   • reason for the test
   • type of test
   • test data
   • expected outcomes
   • valid data should produce the expected results
     • invalid data should produce an error
     • borderline tests the data between valid and invalid

10. authentication

    • having usernames or passwords
    • access rights
      • decides what people can do
      • access rights
    • make users update their passwords regularly and have complex passwords