2.3 Robust Programs

2.3 Robust Programs

1. Defensive Design

   • Methods
     • Anticipate Misuse
       • Input sanitisation
         • SQL Injection
     • Authenticate Users
     • Validate Input
       • range check
       • presence check
       • format check
       • length check
       • check digit
     • Write Maintainable Code
       • Create and Use Sub Programs
       • Use Naming Convention
         • So variables and function names are easily identifiable. This could be using camel case or using underscore to join words.
       • Use indentation to make code easy to read
       • Include comments during code development

2. Testing

   • Types of testing
     • Iterative Testing
     • Final Testing
     • white box testing
     • Black box testing
     • Load testing
   • types of errors
     • Logic
       • when the program runs but the output/outcome is not what is expected for example the programmer has used * instead of +
       • Trace Tables
     • Syntax
       • when the compiler/interpreter does not understand your code because you haven't followed the rules or grammar of the programming language
     • run time error
   • Selecting and using test data
     • Normal Data
     • Boundary Data
     • Valid Data
     • Erroneous Data
   • Purpose of testing