SSR support

[bdariusb]

Hi, I couldn't figure out how to run multi page pre-rendered SvelteKit application, so I ran it as static generated page app with main index.html, because uibuilder requires that to be present at all times. However I would like it to run with server side rendering. So I assume one approach would involve generating a handler.js on build with svelte kit node adapter and passing it down to express js as written here. Would that work with uibuilder?

[TotallyInformation]

Hi, yes, you should be able to run from a non-Node-RED server, the client allows for it. However, it isn't a well-tested approach so we might need to do some rapid tweaks. 😊

To use a 3rd-party server, you generally need to pass some parameters to the uibuilder.start() function that tells the client where the node-red server is and allows it to connect to the correct Socket.IO endpoint. These are documented. This lets you use a completely different web server to your Node-RED data/api server for example.

The alternative would be to use Node-RED/uibuilder to provide the full server. However, I've not really played with SvelteKit so I don't know what that would entail. But still, especially since uibuilder allows you to have an ExpressJS server on a separate port to Node-RED's server and with completely different settings, if you are planning to run your SSR from ExpressJS, it should be possible to do with uibuilder. Untested of course but might be interesting to at least have a try-out to see if it is feasible as it might save you the effort of running a separate web server. Would be a nice contribution to the uibuilder community as well of course.

[bdariusb]

thanks for the answer. I managed to run a custom handler with custom express port. However there still a few problems to solve:

• if handler is an es module, it has to be configured in async manner. I use a dynamic import (import returns a promise):

                import(absolutePath)
                    .then(obj => this.app.use(obj.handler))
                    .catch(...)

• getting absolute/relative path for handler import. Not yet sure how to get absolute path to handler which is served from dist folder. Configuration happens in web.js
• bypass index.html check. Now it's a dummy file but, of course, there should be a nicer approach

[TotallyInformation]

Let me know if there is anything I can help with.

bypass index.html check

Which check is that? I've been wondering whether I should still retain checks on index.html. It is good for people with less experience but could be somewhat limiting.