In express, I have defined some routes
app.post("/api/v1/client", Client.create);
app.get("/api/v1/client", Client.get);
...
I have defined how to handle requests inside a Client controller. Is there a way that I can do some pre-processing to the requests, before handling them in my controller? I specifically want to check if the API caller is authorized to access the route, using the notion of access levels. Any advice would be appreciated.
You can do what you need in a couple of ways.
This will place a middleware that will be used before hitting the router. Make sure the router is added with app.use() after. Middleware order is important.
app.use(function(req, res, next) {
// Put some preprocessing here.
next();
});
app.use(app.router);
You can also use a route middleware.
var someFucntion = function(req, res, next) {
// Put the preprocessing here.
next();
};
app.post("/api/v1/client", someFucntion, Client.create);
This will do a preprocessing step for that route.
Note: Make sure your app.use() invokes are before your route definitions. Defining a route automatically adds app.router to the middleware chain, which may put it ahead of the user defined middleware.