Implement a Quality Gate strategy in your DevOps to fail the build when required
What is a quality gate?
A quality gate is a code quality goal. A quality goal must be enforced before releasing and eventually, before committing to source control.
A dozen of default Quality Gates are proposed by NDepend related to measures like technical debt amount, code coverage or amount of issues with particular severity.
A quality gate is not a rule.
- A rule executed against some code produces some issues.
- A quality gate executed against some code produces a state in the range [ PASS, WARN , FAIL].
Fail the build
Quality Gates can be used to fail the build when certain criteria are not-verified.
When at least one quality gate fails, NDepend.Console.exe returns a non-zero value that can be used to fail the build.
In the Azure DevOps / TFS extension there is the setting Stop the build when at least one Quality Gate fails.
Create your own quality gates
What makes NDepend unique is that a quality gate is a textual C# LINQ Query that can be easily created, edited and customized. For example if you wish to enforce a certain amount of code coverage through a quality gate, you can just write:
// <QualityGate Name="Percentage Code Coverage" Unit="%" />
failif value < 70%
warnif value < 80%
Notice also the special clauses failif (mandatory clause) and warnif (optional clause) that are specific to NDepend CQLinq. codebase.PercentageCoverage is actually a C# statement that NDepend evaluates.
Both the quality gate fail/warn thresholds and its logic are embedded into a short textual query that can be easily edited. The quality gate logic can query anything:
- the code model
- the code coverage data
- the code delta since the baseline
- the issues obtained from executing the rules
- the issues' technical-debt estimations
You can watch this 3 minutes video to get started with the NDepend quality gate: