Serverless Architecture¶

Category: Architecture Tags: serverless, faas, cloud, kubernetes, java

Overview¶

Serverless Architecture delegates infrastructure management to the cloud, allowing you to write functions that execute on demand without managing servers.

What It Is¶

Functions as a Service (FaaS) – Deploy functions, not services
Auto-scaling and pay-per-use
Typically stateless and event-triggered

Why Use It¶

Operational simplicity
Cost efficiency – Pay only for time used
Rapid prototyping

When To Use It¶

Lightweight tasks (e.g., webhooks, image processing)
Event-driven pipelines
Unpredictable or bursty traffic

Implementation Examples¶

Code Example (Java Function)¶

public class HelloHandler implements RequestHandler<Map<String, String>, String> {
    public String handleRequest(Map<String, String> input, Context context) {
        return "Hello, " + input.get("name");
    }
}

Infra Example (Knative on Kubernetes)¶

apiVersion: serving.knative.dev/v1
kind: Service
metadata:
  name: hello-service
spec:
  template:
    spec:
      containers:
      - image: myregistry/hello-fn:latest

Key Concepts Summary¶

Function-based execution
Scales to zero
Stateless and reactive design

Best Practices / Tips¶

Keep functions lightweight and fast
Use managed secrets and env vars for config
Externalize state (e.g., use cloud storage or DB)

Common Issues / Troubleshooting¶

Problem 1: Cold start latency¶

Cause: Function container spin-up delay
Solution: Use provisioned concurrency if supported

Problem 2: Tight vendor lock-in¶

Cause: Proprietary cloud interfaces
Solution: Use open standards like Knative

References / Further Reading¶

https://martinfowler.com/articles/serverless.html
https://knative.dev/docs/