harness-expert

# Harness Expert Skill

Expert knowledge of Harness template types, expression language, pipeline patterns, and deployment strategies.

## Harness Template Types

### 1. Step Templates

**Purpose:** Reusable step configurations across pipelines

**Types:**
- **ShellScript** - Execute bash/PowerShell scripts
- **Run** - Container step with image/command
- **K8sDeploy** - Kubernetes deployments
- **Http** - HTTP calls/webhooks
- **Approval** - Manual approval gates
- **ServiceNow** - ServiceNow integration
- **Custom** - Custom step plugins

**Template Structure:**
```yaml
template:
  name: Deploy to Kubernetes
  type: Step
  spec:
    type: K8sDeploy
    spec:
      service: <+input>
      environment: <+input>
      kubernetesCluster: <+input>
      namespace: <+input>
      releaseName: <+input>
      timeout: <+input.deployment_timeout>
      skipDryRun: false
      allowNoFilesFound: false
      delegateSelectors:
        - <+input.delegate_selector>
```

**Runtime Inputs (Required):**
```yaml
templateInputs:
  spec:
    service:
      serviceRef: <+input.service_name>
    environment:
      environmentRef: <+input.environment_name>
    kubernetesCluster:
      clusterId: <+input.cluster_id>
    namespace: <+input.k8s_namespace>
    releaseName: <+input.release_name>
```

---

### 2. Stage Templates

**Purpose:** Reusable stage definitions with multiple steps

**Template Structure:**
```yaml
template:
  name: Deploy Stage Template
  type: Stage
  spec:
    type: Deployment
    spec:
      service:
        serviceRef: <+input.service_ref>
      infrastructure:
        infrastructureDefinition:
          type: <+input.infra_type>  # Kubernetes, AWS, GCP, etc.
          spec: <+input.infra_spec>
      execution:
        steps:
          - step:
              name: Deploy
              identifier: deploy
              type: K8sDeploy
              spec:
                service: <+input.service_ref>
                environment: <+input.environment_ref>
          - ste