Sometimes, we want to get Express.js to send 404 only on missing routes.
In this article, we’ll look at how to get Express.js to send 404 only on missing routes.
How to get Express.js to send 404 only on missing routes?
To get Express.js to send 404 only on missing routes, we can add a catch-all route at the end of the app.
For instance, we write
const express = require("express");
const app = express.createServer();
const users = [{ name: "abc" }];
app.all("/user/:id/:op?", (req, res, next) => {
req.user = users[req.params.id];
if (req.user) {
next();
} else {
next(new Error("cannot find user ", req.params.id));
}
});
app.get("/user/:id", (req, res) => {
res.send("viewing " + req.user.name);
});
app.get("/user/:id/edit", (req, res) => {
res.send("editing " + req.user.name);
});
app.put("/user/:id", (req, res) => {
res.send("updating " + req.user.name);
});
app.get("*", (req, res) => {
res.send("not found", 404);
});
app.listen(3000);
to add
app.get("*", (req, res) => {
res.send("not found", 404);
});
at the end of the app to add a catch all route with a route handler that only runs when no other URLs listened above it is matched.
We call res.send to send a 404 response.
Conclusion
To get Express.js to send 404 only on missing routes, we can add a catch-all route at the end of the app.
