Openshift: Lab 14 – Setting up and using OpenShift Serverless Functions

Manual – https://docs.redhat.com/en/documentation/red_hat_openshift_serverless/1.30/html/functions/index

OpenShift Serverless Function is a feature of Red Hat OpenShift that enables you to build, deploy, and manage event-driven serverless workloads using the Function-as-a-Service (FaaS) paradigm, directly on OpenShift. It is built on top of Knative (an open-source Kubernetes-based serverless framework), but provides a more developer-friendly and integrated experience for creating “functions”—small, single-purpose pieces of code that run in response to events.

Key Points about OpenShift Serverless Function

1. What is a Serverless Function?

• A serverless function is a small piece of code that is executed in response to an event (HTTP request, message in a queue, etc.).
• You don’t manage the underlying servers; OpenShift/Kubernetes automatically scales the function up or down (even to zero) based on demand.

2. How does OpenShift Serverless Function work?

• Functions are created using a CLI (kn func or oc) or the OpenShift web console.
• Functions can be written in languages like Node.js, Python, Go, Java, Quarkus, TypeScript, etc.
• Code is packaged as a container image and deployed as a Knative Service.
• OpenShift automatically handles scaling, routing, and event integration.

3. Why use OpenShift Serverless Function?

• Rapid development: Focus on writing business logic; the platform handles build, deployment, and scaling.
• Event-driven: Functions can be triggered by events like HTTP requests, Kafka messages, or cloud events.
• Efficient resource usage: Functions scale to zero when not in use, saving costs and resources.
• Integrated developer experience: CLI and IDE tools help you scaffold, build, test, and deploy functions easily.

4. How is it different from plain Knative?

• OpenShift Serverless Function provides a streamlined developer workflow and templates, plus deeper integration with OpenShift features (e.g., pipelines, security, monitoring).
• Focuses on the function lifecycle (scaffolding, local development, automated builds) versus raw Knative, where you deal more with YAML and manual setup.

Typical Workflow

1. Initialize a Function: kn func create --runtime node --name hello-func
2. Develop Locally: Write your logic (e.g., index.js or app.py).
3. Build and Deploy: kn func deploy
   • This builds the function, creates a container image, and deploys it as a Knative Service.
4. Trigger the Function: By HTTP request, event source, or via API gateway.
5. Auto-scaling: OpenShift will scale the function pods up/down based on incoming events (can scale down to zero).

Common Use Cases

• API endpoints (microservices)
• Data transformation pipelines
• Event-driven automation (e.g., on new file upload, process file)
• Webhooks
• Lightweight background tasks

Summary Table

References

• OpenShift Serverless Functions Official Docs
• Red Hat Blog: Getting Started with OpenShift Functions
• Knative Functions

Rajesh Kumar

I’m a DevOps/SRE/DevSecOps/Cloud Expert passionate about sharing knowledge and experiences. I have worked at Cotocus. I share tech blog at DevOps School, travel stories at Holiday Landmark, stock market tips at Stocks Mantra, health and fitness guidance at My Medic Plus, product reviews at TrueReviewNow , and SEO strategies at Wizbrand.

Do you want to learn Quantum Computing?

Please find my social handles as below;

Rajesh Kumar Personal Website
Rajesh Kumar at YOUTUBE
Rajesh Kumar at INSTAGRAM
Rajesh Kumar at X
Rajesh Kumar at FACEBOOK
Rajesh Kumar at LINKEDIN
Rajesh Kumar at WIZBRAND

Rajesh Kumar DailyLogs