BEGINNER • API Foundations and HTTP
Endpoint Design Lab for booking reservation API #26
This lesson targets improve endpoint reliability in a realistic booking reservation API workflow. You will practice commands: npm install express | curl http://localhost:3000/health | res.status(200).json(...). The code example is specific to backend API engineering tasks for this lesson objective.
Code Example
import { z } from "zod";
const createUserSchema = z.object({
email: z.string().email(),
password: z.string().min(8),
role: z.enum(["user", "admin"]).default("user"),
});
export function parseCreateUser(payload: unknown) {
const result = createUserSchema.safeParse(payload);
if (!result.success) {
return {
ok: false,
error: result.error.issues.map((issue) => issue.message),
};
}
return { ok: true, data: result.data };
}
console.log("Try endpoint with:", "curl http://localhost:3000/health");Commands & References
- npm install express
- curl http://localhost:3000/health
- res.status(200).json(...)
Lab Steps
- Prepare environment using: npm install express
- Implement endpoint or middleware for this scenario.
- Test positive/negative cases and inspect response contracts.
- Document one reliability or security improvement.
Exercises
- Add one edge-case validation and return clear error details.
- Improve one endpoint to be idempotent and test retries.
- Write one test case proving the expected API behavior.