Integrating CD with other Harness modules

Learn how the CD module works with other Harness modules.

This topic describes a few of the cross-module use cases in the Harness platform.

Harness Continuous Integration

You can couple Harness Continuous Integration (CI) and Continuous Delivery (CD) in a single pipeline.

You can use Harness CI as the first stage in the pipeline to build, test, and push your app to a repo, and then have a subsequent CD stage pull that app version from the repo and deploy it to a dev, QA, or prod environment.

Here's the YAML for a simple example that builds and pushes an app in the CI stage and then pulls and deploys the app in the CD stage.

YAML

pipeline:
  name: tweety
  identifier: tweety
  projectIdentifier: CD_Docs
  orgIdentifier: default
  tags: {}
  properties:
    ci:
      codebase:
        connectorRef: tweetapp
        build: <+input>
  stages:
    - stage:
        name: Tweetapp
        identifier: Tweetapp
        type: CI
        spec:
          cloneCodebase: true
          infrastructure:
            type: KubernetesDirect
            spec:
              connectorRef: docimmut
              namespace: default
              automountServiceAccountToken: true
              nodeSelector: {}
              os: Linux
          execution:
            steps:
              - step:
                  type: BuildAndPushDockerRegistry
                  name: Build Tweet App
                  identifier: Build_Tweet_App
                  spec:
                    connectorRef: Docker_Hub_with_Pwd
                    repo: cretzman/tweetapp
                    tags:
                      - <+pipeline.sequenceId>
          service:
            serviceRef: ""
        variables: []
    - stage:
        name: deploy tweety
        identifier: deploy_tweety
        description: ""
        type: Deployment
        spec:
          deploymentType: Kubernetes
          service:
            serviceRef: Tweety
          environment:
            environmentRef: Tweety
            deployToAll: false
            infrastructureDefinitions:
              - identifier: Tweety
          execution:
            steps:
              - step:
                  name: Rollout Deployment
                  identifier: rolloutDeployment
                  type: K8sRollingDeploy
                  timeout: 10m
                  spec:
                    skipDryRun: false
                    pruningEnabled: false
            rollbackSteps:
              - step:
                  name: Rollback Rollout Deployment
                  identifier: rollbackRolloutDeployment
                  type: K8sRollingRollback
                  timeout: 10m
                  spec:
                    pruningEnabled: false
        tags: {}
        failureStrategies:
          - onFailure:
              errors:
                - AllErrors
              action:
                type: StageRollback
        when:
          pipelineStatus: Success
  allowStageExecutions: true

Here's what the pipeline looks like in pipeline studio:

CI stage

Here's the push step from the CI stage:

Click to view full size image

Note the <+pipeline.sequenceId> expression. This is used to tag the artifact pushed to Docker Hub. You can tag your artifact versions in a number of ways. The expression <+pipeline.sequenceId> is incremented each time the pipeline is run.

The expression <+pipeline.sequenceId> will be used in the subsequent CD stage to fetch the app version.

CD stage

Here's the Kubernetes Rollout Deployment step from the CD stage.

Click to view full size image

In the stage's service, the expression <+pipeline.sequenceId> is used pull the app version.

picture 2

It's that simple to integrate Harness CI and CD.

Learn more

This was just a simple introduction to the integration.

For a longer tutorial of Harness CI and CD integration, go to End-To-End CI/CD Pipeline.

Harness Chaos Engineering

The Harness Chaos Engineering (HCE) integration with Harness CD allows chaos experiments to be executed as part of a Harness CD pipeline.

Harness Feature Management & Experimentation

You can integrate Harness Feature Management & Experimentation into your Harness CD pipelines to manage feature flags as part of your deployment workflow.

By adding FME steps to CD stages, you can create, update, target, and disable feature flags during a pipeline execution. This allows feature flag operations to be versioned, reviewed, and executed alongside application deployments, reducing manual steps and improving release coordination.

You can integrate Harness FME with CD pipelines in the following ways:

• Creating or updating feature flags as part of a release

• Managing individual targeting lists during staged rollouts

• Adjusting default traffic allocations when deploying a new version

• Killing a feature flag immediately in response to deployment issues

For more information, see the Pipelines documentation.