SSR Hydration

[futursolo]

Description

This pull request brings SSR Hydration to Yew.

Fixes #41
Fixes #2403

This pull request consists of the following changes:

1. Fixed pr-flow on macOS, alongside with some tests that was skipped in the past.
2. Added Renderer and Renderer::hydrate for Hydration.
3. Added a function router example equivalent to router example.
4. Added ssr router example that renders function router example on the server side and hydrates it on the client side.
5. Scheduler now always renders parent component before child component
   (This is done to ensure NodeRef of parents can be fixed before child components, should also be beneficial in client-side rendering as well.)
6. The application will now panic if you try to suspend from a fallback component. (This was previously an undefined behaviour where the last non-suspended rendered DOM of the fallback component will be shown.)

Suspense

Event replay is not implemented, this does not matter too much unless your Suspense is very slow.

This is kind of difficult with the current event system.
I guess it can be dealt with in a future PR.

Checklist

• I have run cargo make pr-flow
• I have reviewed my own code
• I have added tests

[github-actions]

Visit the preview URL for this PR (updated for commit b4a2616):

https://yew-rs--pr2453-hydration-1ikzdrq3.web.app

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[ranile]

Looks good to me, for the most part. Just a few comments. This is great addition, thank you for implementing it.

[futursolo]

I haven't been following #2330 and this PR was done under the impression of #2330 wouldn't be landed at anytime soon.

The implementation will need some re-visitation if #2330 is merged before it.

If #2330 is merged before this pull request (which I am fine with and actually prefer), I will close this PR and split this into multiple smaller pull requests to avoid having to resolve conflicts on a big changeset repeatedly.

[WorldSEnder]

If you need a quick run down of specific changes in #2330 , feel free to ping me here or on discord. In general I'd say you want to hydrate bundle nodes instead of virtual nodes and that's all that needs to change (on the surface, anyway) and should cover most conflicts.

Also, thanks for the ssr examples, good to have them :)

[ranile]

@futursolo @WorldSEnder, we can merge the one which will cause less conflicts with the other. Which one should go first? I wanted to get #2330 in first because it's been sitting for way too long but if that will cause this PR issues and merging this PR will not make that one much harder to fix conflicts and merge, then I'd be happy with merging this first.

[futursolo]

There's no easy way out of this situation. Whichever that is merged later is going to have to re-implement hydration on bundle nodes.
However, #2453 can be split into multiple smaller pull requests to avoid resolving conflicts repeatedly.

I guess #2330 should be given priority regardless of the difficulty to resolve conflicts for other PRs as it is taking too long to merge and any upcoming pull request needs to take consideration of it.

So I guess #2330 -> #2453 was the preferred order if nothing is merged in the meanwhile to make #2330 become unable to merge again.