Express 5 cheatsheet

Express 5: Middleware

6 common Express 5 tasks.

Write middleware

Run code on every request, then call next() to continue.

app.use((req, res, next) => {
  console.log(req.method, req.url);
  next();
});

Serve files from the public folder.

app.use(express.static("public"));

Allow browsers on other origins to call your API.

npm install cors

import cors from "cors";
app.use(cors({ origin: "https://app.example.com" }));

Add common protective HTTP headers.

npm install helmet

import helmet from "helmet";
app.use(helmet());

Log each request with the morgan middleware.

npm install morgan

import morgan from "morgan";
app.use(morgan("combined"));

Read the client's real IP and protocol behind a proxy such as Nginx.

app.set("trust proxy", 1);