Express middleware compatibility

[robokozo]

Does anyone have an example of wrapping an express middleware for compatibility with nitro/h3? My company exclusively relies on old express middleware that prevent me from writing new code with nitro.

I believe defineEventHandlers event param has req and res available on it... but I'm not sure if those are compatible with express. For reference, express middlewares provide: (req, res, next) => { next() }

Would it be something like:

export default defineEventHandler(async (event) => {
  await new Promise((resolve) => {
    myExpressMiddleware(event.node.req, event.node.res, resolve);
  });
});

[robokozo]

It looks a little more involved. From what I see, in express the res object has a bunch of functions on it that would need to be adapted for nitro.

Like a res.send("foo") in express would just be a return "foo" in nitro/h3

[peterroe]

Hi, H3 is compatible with express middleware. For your case, you can do like this:

export default fromNodeMiddleware((req, res, next) => {
    myExpressMiddleware(req, res, next);
})

Or we could even make it simpler.

export default fromNodeMiddleware(myExpressMiddleware)

[robokozo]

@peterroe wow! even better! thank you <3