Node.js - Expressjs middleware to extend res.render

express, middleware, node.js

Solution

`app.locals` is likely what you're looking for:

app.locals(settings.template_defaults);

Along with `res.locals` and `res.render`, Express is already capable of merging the values for you:

// locals for all views in the application
app.locals(settings.template_defaults);

// middleware for common locals with request-specific values
app.use(function (req, res, next) {
    res.locals({
        // e.g. session: req.session
    });
    next();
});

// and locals specific to the route
app.get('...', function (req, res) {
    res.render('...', {
        // ...
    });
});

Problem

I'd like to know if there is a built in way to extend Express.js's res.render function because, I'd like to pass a default set of "locals" to every template that is rendered. Currently I've written a small middleware that uses underscore.js's extend function to merge the default "locals" and the ones specific for that template: ``` app.use(function(req, res, next){ res.render2 = function (view, locals, fn) { res.render(view, _.extend(settings.template_defaults, locals), fn); }; next(); }); ``` Is there a better way to do this?

Original source