Conceptos básicos de despliegue en plataforma

mkdir platform-api && cd platform-api
npm init -y
npm pkg set type=module
npm install express@5
npm install -D typescript@5.6

import { z } from "zod";
 
const envSchema = z.object({
  PORT: z.coerce.number().default(3000),
  NODE_ENV: z.enum(["development", "production", "test"]),
  DATABASE_URL: z.string().url(),
});
 
export const env = envSchema.parse(process.env);

import express from "express";
import { env } from "./env.js";
 
const app = express();
app.get("/health", (_req, res) => res.json({ status: "ok" }));
 
app.listen(env.PORT, "0.0.0.0");

app.use((req, res, next) => {
  const start = Date.now();
  res.on("finish", () => {
    console.log(JSON.stringify({
      method: req.method,
      path: req.path,
      status: res.statusCode,
      ms: Date.now() - start,
    }));
  });
  next();
});

// Malo: almacén de sesiones en memoria a escala
const sessions = new Map<string, string>();
 
// Bueno: almacén de sesiones de Redis o DB
import { getSession } from "./session-store.js";

# Fase de liberación (Job / initContainer)
npx prisma migrate deploy
 
# Fase de ejecución (Deployment CMD)
node dist/main.js

app.get("/health", (_req, res) => res.json({ status: "ok" }));
app.get("/ready", async (_req, res) => {
  const ok = await pingDatabase();
  res.status(ok ? 200 : 503).json({ status: ok ? "ready" : "not_ready" });
});

env:
  - name: NODE_ENV
    value: production

apiVersion: apps/v1
kind: Deployment
metadata:
  name: api
spec:
  replicas: 3
  selector:
    matchLabels:
      app: api
  template:
    metadata:
      labels:
        app: api
    spec:
      containers:
        - name: api
          image: ghcr.io/acme/api:sha-abc123
          ports:
            - name: http
              containerPort: 3000
          envFrom:
            - configMapRef:
                name: api-config
            - secretRef:
                name: api-secrets
          readinessProbe:
            httpGet:
              path: /ready
              port: http
          livenessProbe:
            httpGet:
              path: /health
              port: http

const server = app.listen(env.PORT, "0.0.0.0");
 
process.on("SIGTERM", () => {
  server.close(() => process.exit(0));
});