Code coverage reports in Jenkins - Step-by-Step Execution

Process Flow - Code coverage reports

Start Jenkins Job

↓

Run Tests with Coverage

↓

Generate Coverage Report

↓

Publish Report in Jenkins

↓

View Coverage Results

↓

Decide on Code Quality

↓

End

The Jenkins job runs tests with coverage enabled, generates a report, publishes it, and then you view the results to check code quality.

Execution Sample

Jenkins

pipeline {
  agent any
  stages {
    stage('Test') {
      steps {
        sh 'pytest --cov=./ --cov-report=xml'
      }
    }
    stage('Publish Coverage') {
      steps {
        publishCoverage adapters: [coberturaAdapter('coverage.xml')]
      }
    }
  }
}

This Jenkins pipeline runs tests with coverage and publishes the coverage report.

Process Table

Step	Action	Command/Tool	Result
1	Start Jenkins job	Jenkins	Job triggered and environment prepared
2	Run tests with coverage	pytest --cov=./ --cov-report=xml	Tests run, coverage data collected
3	Generate coverage report	pytest outputs coverage.xml	coverage.xml file created
4	Publish coverage report	publishCoverage with coberturaAdapter	Coverage report published in Jenkins UI
5	View coverage results	User views Jenkins coverage tab	Coverage percentages displayed
6	Decide on code quality	User reviews report	Decide to accept or improve code coverage

💡 All steps complete, coverage report available for review

Status Tracker

Variable	Start	After Step 2	After Step 3	After Step 4	Final
coverage_data	none	collected during tests	saved in coverage.xml	published in Jenkins	available for viewing

Key Moments - 2 Insights

Why do we need to run tests with coverage enabled before generating the report?

Because coverage data is collected during test execution (see execution_table step 2). Without running tests, there is no data to generate a report.

What does the publishCoverage step do in Jenkins?

It takes the coverage report file (coverage.xml) and makes it visible in Jenkins UI (see execution_table step 4). This helps users see coverage results easily.

Visual Quiz - 3 Questions

Look at the execution table, at which step is the coverage.xml file created?

A Step 3

B Step 2

C Step 4

D Step 5

💡 Hint

Check the 'Generate coverage report' action in the execution_table

According to the variable tracker, when is coverage_data first collected?

A After Step 3

B After Step 1

C After Step 2

D After Step 4

💡 Hint

Look at coverage_data changes in variable_tracker after each step

If the publishCoverage step is skipped, what happens to the coverage report visibility?

A Report is still visible in Jenkins UI

B Report is generated but not visible in Jenkins UI

C Tests won't run

D Coverage data won't be collected

💡 Hint

Refer to execution_table step 4 about publishing coverage

Concept Snapshot

Jenkins Code Coverage Reports:
- Run tests with coverage enabled (e.g., pytest --cov)
- Coverage data saved in a report file (coverage.xml)
- Use publishCoverage step to show report in Jenkins UI
- View coverage results to assess code quality
- Helps ensure tests cover important code parts

Full Transcript

In Jenkins, code coverage reports are created by running tests with coverage enabled, which collects data about which parts of the code were tested. This data is saved in a file like coverage.xml. Then, Jenkins uses a publishCoverage step to display this report in its user interface. Users can view the coverage percentages and decide if the code quality is good or needs improvement. The process starts with triggering the Jenkins job, running tests, generating the report, publishing it, and finally viewing the results.