Mercure-Hub: 5. GitLab CI

This documentation is part of the GitHub Actions & GitLab CI guide. View the full guide here: Spin up a real Mercure Hub service from your GitHub Actions or GitLab CI pipeline, run your tests against it, and tear it down automatically.

👋 Welcome to the Stackhero documentation!

Stackhero provides a fully managed Mercure-Hub cloud service designed to make real-time data delivery simple and reliable. You get:

• Unlimited requests and message sizes for complete flexibility.
• A custom domain with built-in HTTPS security (for example, https://real-time.your-company.com).
• Effortless one-click updates to keep your hub up to date with zero hassle.
• High performance and strong security on a private, dedicated infrastructure.
• Multiple regions: 🇪🇺 Europe and 🇺🇸 USA for low-latency delivery.

Get up and running fast: it takes just 5 minutes to launch your Mercure-Hub cloud hosting environment and start pushing real-time updates to your applications.

You can save this configuration as .gitlab-ci.yml. With this setup, every pipeline run spins up a fresh real Mercure Hub for your tests.

test:
  image: ubuntu:24.04
  variables:
    STACK_NAME: "ci-mercure-hub-$CI_PIPELINE_ID-$CI_JOB_ID"
    INSTANCE: "20G"   # Change this as needed (see step 3)
    REGION: "europe"
    SERVICE_STORE: "mercure-hub"
  # STACKHERO_TOKEN comes from the CI/CD variable you created in step 1.
  script:
    - set -euo pipefail
    - curl -fsSL https://www.stackhero.io/install.sh | sh
    - apt-get update && apt-get install -y --no-install-recommends jq curl
    - STACK_ID=$(stackhero --format=script stack-create --name="$STACK_NAME")
    - echo "STACK_ID=$STACK_ID" >> deploy.env
    - SERVICE_ID=$(stackhero --format=script service-add --stack="$STACK_ID" --service-store="$SERVICE_STORE" --instance="$INSTANCE" --region="$REGION")
    - echo "SERVICE_ID=$SERVICE_ID" >> deploy.env
    - stackhero service-wait-for --service="$SERVICE_ID"
    - config=$(stackhero service-configuration-get --service="$SERVICE_ID" --format=json)
    - host=$(echo "$config" | jq -r '.configuration.domain')
    # Request the hub endpoint and check it answers.
    - curl -fsS -o /dev/null -w "%{http_code}" "https://$host/.well-known/mercure?topic=test" | grep -qE "^(200|400|401)$"
    - echo "✅ Mercure Hub is reachable from CI."
    # You can run your own test suite here using the credentials above ...
  after_script:
    - test -f deploy.env && . ./deploy.env || true
    - >
      if [ -n "${SERVICE_ID:-}" ]; then
        stackhero service-delete --service="$SERVICE_ID" --confirm
        stackhero service-wait-for --service="$SERVICE_ID"
      fi
    - >
      if [ -n "${STACK_ID:-}" ]; then
        stackhero stack-delete --stack="$STACK_ID" --confirm
      fi

In GitLab, cleanup happens inside after_script. This section is always executed, even if the job fails, so your Mercure Hub resources are removed and you are not charged for resources you are not using.

In GitLab, after_script runs in a fresh shell. To handle this, the script writes the service and stack IDs to deploy.env during the job and reloads them before teardown. This makes sure that even if something fails mid-job, your resources are still cleaned up.

That is the complete CI lifecycle for Mercure Hub: create a stack, add the service, wait, retrieve credentials, smoke-test, and always tear down. Each pipeline run gets a real, isolated service, nothing left running when you are done. For more information about available commands and non-interactive STACKHERO_TOKEN authentication, you may want to explore the full CLI documentation.