SQALE SonarQube Rating

Andrew picture Andrew · Feb 2, 2016 · Viewed 8.8k times · Source

I'm using sonar to analyze a set of related projects. And I'm using SQALE Rating to justify the need for a refactoring

My question is what is the logic behind SQALE to Technical Debt ratio mapping?

Why SQALE A rating is Tech Debt in range from 0% to 5%. But not 0% to 3% for instance? How should I define a SQALE rating limits? Why 5% Tech debt is good? Is there any methodology I can use? Or i have to come up with this standards by my own? And is there a way in SonarQube to change them?

Answer

The SQALE Rating is a direct correlation with the Technical Debt Ratio of your project. The Technical Debt Ratio is the following:

  • The technical debt of your project (= sum of the debt of all issues)
  • Divided by the estimation of the cost to rewrite your application from scratch

The idea is to tell you that if this ratio "Debt vs. cost to rewrite" grows too high, maybe it's a good time to rewrite the application instead of spending time reimbursing your debt.

By default, SonarQube is configured to give a A rating when the ratio is below 5%. But this is just a default configuration that you can override in the global administration page under "Configuration > General Settings > Technical Debt".