Question/Feature suggestion: Server side rendering

[AlterionX]

Is server side rendering being considered at all?

It seems borderline impossible in my head without severe restrictions, but I was just wondering.

[MartinKavik]

Why do you need it?

I use Seed as a static site generator as an alternative. See seed-quickstart-webpack for an example.

[AlterionX]

I've got a login system that dynamically changes the nav menu. I think I want this to happen on the server, since if someone navigates to my site, they'll see the nav menu flash.

To do this, I think I need some form of SSR? Then I got carried away thinking about everything else that could use it.

Also, the rest of my static pages uses maud for rendering, so then I'd need to combine those two systems.

Totally missed the quickstart thing, btw, so thanks.

[MartinKavik]

nav menu flash

I want to fix one type of flashes - see issue https://github.com/David-OConnor/seed/issues/223.

But you probably think the flash of content once you loaded info about user and want to show e.g. his name and avatar in the menu. I think there are at least two options:

1. If the site is NOT prerendered, you can load required data in init function (ideally from localStorage - we want it to be synchronous and fast). E.g. seed-rs-realworld uses localStorage that way.

2. If the site IS prerendered, you can load required data also in init function, but you don't want to block first render. So you can show some placeholders or spinner instead of dynamic page parts.

   • Example of placeholders: leerob.io/blog/loading-placeholder-with-sass.
   • Seed example with spinner: seed-quickstart-webpack.netlify.com - change the window width to see hamburger and enable throttling in dev tools. Don't do the same mistake like me - inline you images or otherwise your icons can disappear/show too late during loading. Code is here.

Also, the rest of my static pages uses maud for rendering, so then I'd need to combine those two systems.

Try to render maud templates into String in init and then render the result in view function with macro raw!í..). Prerender your app and you get HTML static files.

[AlterionX]

Well, the real problem I had was how to hook up event listeners, because the wasm is still traveling over the wire and not initialized yet.

The thing about prerendering is that I don't want to write out the templates twice, once with listeners for Seed, and once without for maud. Ideally, I would create another macro or something similar that somehow wraps Seed's things so that I can use maud's html macro directly. Well, I'll see, I guess.

Also, I just made a PR to allow for the initial run to do some bootstrapping. Hopefully, this is a step in the right direction for fixing #223.

[dlight]

@MartinKavik

Why do you need it?

Hi! My use case is to do the first render on the server, and then "rehydrate" the client to work on a prerendered page. This speeds up the first render and may enable the site to be used with scripts disabled (with some effort).

[MartinKavik]

@dlight Hi. I would like to know more info, if possible:

• Why you can't use standard prerendering? (User-specific content, many parts with dynamic content..)
• How fast is your first render now and how fast you want it to be?
• What's your backend framework / where will be Seed app hosted?
• "scripts disabled" - do you have some special users/customers with disabled scripting or you mean something like bots / web scrapers?

[flosse]

@MartinKavik I have a related usecase on the client side.

I want to render a SVG graphic as String so that I can use it as background property. Currently I have to hardcode/build the SVG string like this:

const SVG_BG: &str = concat!(
    "<svg xmlns='http://www.w3.org/2000/svg' width='10' height='10'>",
    "<rect width='10' height='10' fill='rgba(76,76,76,1)' />",
    "<line x1='0' y1='5' x2='10' y2='5' stroke='rgba(255,255,255,0.25)' stroke-width='0.125' />",
    "<line x1='5' y1='0' x2='5' y2='10' stroke='rgba(255,255,255,0.25)' stroke-width='0.125' />",
    "</svg>"
);

And here it is used:

let my_style = style! {
    St::BackgroundImage => format!(r#"url("data:image/svg+xml;utf8,{}")"#, SVG_BG);
}

It would be cool to do this dynamically like this:

let svg_bg = a_seed_view_fn(parameters).to_html_string();
let my_style = style! {
    St::BackgroundImage => format!(r#"url("data:image/svg+xml;utf8,{}")"#, svg_bg);
}

[MartinKavik]

@flosse Isn't it more related to https://github.com/seed-rs/seed/issues/294 or https://github.com/seed-rs/seed/issues/414?

[flosse]

@flosse Isn't it more related to #294 or #414?

Absolutely! I'm sorry for messing up the thread!

[MartinKavik]

@flosse NP, it's somehow related and I'll need this feature too in Seed's core so we can implement some bigger performance optimizations.

[mikezupper]

@MartinKavik - An e-commerce catalog is the perfect use case... SEO is critical. You would SSR the pages for SEO/perf reasons (static generation or actix-web, rocket, etc). Once that content gets consumed via browser user, the seed wasm module should preload the state based on the already loaded in DOM. Or Maybe something on the server can embed “state init” info that can be easily loaded into wasm module. My thoughts immediately go to “event sourcing” ideas... replaying the events to reconstruct the end state. Thoughts? Should I clarify in anyway?

[MartinKavik]

@mikezupper

• Personally I try to write apps the way where the client app is "smart" and the backend is "dumb". You can notice it on seed-rs.org - Time Tracker example communicates with a graph database directly through GraphQL - there is no custom server at all.
• From the maintainer's point of view, I assume SSR would introduce a lot of new code and changes. It means more bugs and maybe bigger file size and reduced performance. But I may be wrong - feel free to experiment with the implementation and create a draft PR once it's ready for a discussion / code review.
• If I would need to have perfect SEO for most pages and server-side rendering, I would probably look for something like Phoenix LiveView.
• Or I would try prerendering on the fly / on shedule - see e.g. https://advancedweb.dev/prerendering. There are many services, open-source projects and tutorials about it (e.g. https://codelabs.developers.google.com/codelabs/dynamic-rendering)

[pyrossh]

Sauron has implemented prerendering. Maybe you can take a look at that in this example, https://github.com/ivanceras/sauron/tree/master/examples/progressive-rendering