How to annotate Express middlewares with JSDoc?

Question

I'm trying to document an Express middleware, but the build-in validation tool in WebStorm tells me that types are incorrectly assigned in the following JSDoc block:

/**
 * My middleware.
 *
 * @param {Object} req
 * @param {Object} res
 * @param {Function} next
 * @return {Object}
 */
exports.show = function(req, res, next) {
    ...
};

In Express sources, I didn't find any @typedefs to help me. Also, I want to avoid things like @param {*}.

What is the correct way to document Express middleware using JSDoc? Thanks for any help.

Answer 1

Use DefinitelyTyped

1. Install express types npm install --save-dev @types/express
2. use e.Response as usually @param {e.Response} res

More types

• in file /node_modules/@types/express/index.d.ts
• for Response it is e.Response because:

... declare namespace e { ... export interface Response extends core.Response { } ...

WebStorm

install types via Settings > Languages & Frameworks > Javascript > Libraries > @types/express