Harness | Core Concepts

 Core components of Harness

1. Application

An Application is the top-level container in Harness.

• It represents a complete project or system
• Contains all services, environments, workflows, and pipelines for that project

Example

Application: E-commerce Platform

Inside it you may have:

• payment-service
• order-service
• notification-service

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2. Service

A Service represents a deployable microservice or application component.

It defines:

• Artifacts (Docker image, JAR, ZIP, etc.)
• Service configuration
• Deployment variables

Example

Service: Order Service

Artifacts:

• Docker image from Docker
• JAR file from a repository
• Lambda package

Possible service types include:

• Secure Shell
• Kubernetes
• AWS Lambda
• ECS

Example:

• If deploying a container to Kubernetes → Kubernetes service type
• If deploying serverless → use AWS Lambda service type.

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3. Environment

An Environment represents where the service will be deployed.

Typical environments:

• Dev
• QA
• Staging
• Production

It defines:

• Infrastructure
• Cloud provider
• Target cluster or server

Example:
Environment: Production

Infrastructure:

• Kubernetes cluster
• AWS account
• VM instances

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4. Workflow

Workflows are part of First Gen Harness in Next Gen Harness its moved under Pipelines Execution.

A Workflow defines how the deployment happens.

It contains:

• Deployment steps
• Pre-deployment tasks
• Post-deployment verification
• Rollback steps

Example workflow steps:

1. Pull artifact
2. Deploy container
3. Run database migration
4. Perform health check
5. Verify deployment

Harness can also integrate with monitoring tools for verification.

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5. Pipeline

A Pipeline orchestrates multiple workflows.

It allows:

• Sequential deployments
• Multi-environment promotion
• Approval gates

Example pipeline:

Build → Dev Deploy → QA Deploy → Approval → Production Deploy

Example integration:

• Build triggered from Jenkins
• Deploy to Kubernetes cluster

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Complete Example

Application

Online Banking System

Services

• account-service
• transaction-service
• notification-service

Environments

• Dev
• QA
• Production

Workflow

Deploy container → Run health check → Verify logs

Pipeline

Build → Dev → QA → Manual Approval → Production

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Easy way to remember

• Application → Project
• Service → What you deploy
• Environment → Where you deploy
• Workflow → How you deploy
• Pipeline → Deployment process across environments