You should see them in the Tests tab on the Pipelines :

https://gitlab.com/{group}/{project}/-/pipelines/{pipeline_id}/test_report

Example :

You also have access to the report on the Merge Request if you have one open :

To see the coverage you need to configure the coverage keyword in the job :

coverage:
  script:
    - mvn clean install surefire-report:report
  image: maven:3.9.9-sapmachine-23
  stage: coverage
  coverage: /Total.*?([0-9]{1,3})%/
  artifacts:
    [...]

This will tell to Gitlab the regex to use to get the coverage based on your coverage tool, here Jacoco. Based on the documentation :

After a pipeline runs successfully, you can view code coverage results in:

• Merge request widget: See the coverage percentage and changes compared to the target branch.

• Merge request widget showing code coverage percentage

• Merge request diff: Review which lines are covered by tests. Available with Cobertura and JaCoCo reports. Pipeline jobs: Monitor coverage results for individual jobs.

GitLab employee here.

If your administrator has GitLab pages set up, you can see the URL that your artifact deployed to by going (on your project) to Settings -> Pages.

There you should see:

Congratulations! Your pages are served under: https://your-namespace.example.com/your-project

Click on that link and you should be good to go! Also we are expanding support for HTML artifacts. This issue and it’s related issues talk about existing and upcoming features that may expand on what you’ve built here.

GitLab Community Edition 15.7.6

parse_jacoco.sh

#!/bin/bash

# Check if the JaCoCo XML file path is provided
if [ $# -eq 0 ]; then
    echo "Please provide the JaCoCo XML report file path"
    exit 1
fi

JACOCO_XML=$1

# Check if the file exists
if [ ! -f "$JACOCO_XML" ]; then
    echo "File not found: $JACOCO_XML"
    exit 1
fi

# Ensure xmllint is installed
if ! command -v xmllint &> /dev/null; then
    echo "xmllint is not installed. Please install libxml2-utils"
    exit 1
fi

# Define a function to calculate coverage percentage
calculate_coverage() {
    local covered=$1
    local missed=$2
    local total=$((covered + missed))
    if [ $total -eq 0 ]; then
        echo "0.0"
    else
        echo "scale=1; $covered * 100 / $total" | bc
    fi
}

echo "Coverage Data:"

# Initialize total instruction coverage counters
total_instruction_covered=0
total_instruction_missed=0

# Get coverage for various types
for type in INSTRUCTION BRANCH LINE COMPLEXITY METHOD CLASS; do
    covered=$(xmllint --xpath "sum(/report/counter[@type='$type']/@covered)" $JACOCO_XML)
    missed=$(xmllint --xpath "sum(/report/counter[@type='$type']/@missed)" $JACOCO_XML)
    total=$((covered + missed))
    coverage=$(calculate_coverage $covered $missed)
    echo "${type} Coverage: ${covered} covered, ${missed} missed, ${total} total (${coverage}%)"

    # Accumulate INSTRUCTION coverage as the total coverage
    if [ "$type" = "INSTRUCTION" ]; then
        total_instruction_covered=$covered
        total_instruction_missed=$missed
    fi
done

# Calculate and output total coverage (echo here for GitLab usage)
total_coverage=$(calculate_coverage $total_instruction_covered $total_instruction_missed)
echo "Total Coverage: ${total_coverage}%"

gitlab config

stages:
  - test
  - visualize

test-job:
  stage: test
  image: maven:3.3-jdk-8
  script:
    - mvn verify
  artifacts:
    when: always
    reports:
      junit:
        - target/surefire-reports/TEST-*.xml
        - target/failsafe-reports/TEST-*.xml
    paths:
      - target/site/jacoco/jacoco.xml
  tags:
    - docker-runner

coverage-job:
  stage: visualize
  image: alpine:latest
  before_script:
    - apk add --no-cache libxml2-utils
  script:
    - ./parse_jacoco.sh target/site/jacoco/jacoco.xml
  coverage: '/Total Coverage: (\d+\.\d+)%/'
  needs: ["test-job"]
  tags:
    - docker-runner