Sometimes, we want to implement user permissions with Node.js and Express.js

in this article, we’ll look at how to implement user permissions with Node.js and Express.js.

How to implement user permissions with Node.js and Express.js?

To implement user permissions with Node.js and Express.js, we can define a function that returns a middleware function that checks the role of the user and acts accordingly.

For instance, we write

const requireRole = (role) => {
  return (req, res, next) => {
    if (req.session.user && req.session.user.role === role) {
      next();
    } else {
      res.send(403);
    }
  }
}

app.get("/foo", foo.index);
app.get("/foo/:id", requireRole("user"), foo.show);
app.post("/foo", requireRole("admin"), foo.create);

app.all("/foo/bar", requireRole("admin"));
app.all("/foo/bar/*", requireRole("user"));

to define the requireRole function that returns a middleware function that checks the role of the user with req.session.user.role === role.

And if the user has the role, then we call next to call the route middleware.

Otherwise, we return a 403 response.

Then we use requireRole by calling it with the role name before the route handler method in app.get, app.post, and app.all.

Conclusion

To implement user permissions with Node.js and Express.js, we can define a function that returns a middleware function that checks the role of the user and acts accordingly.