Invalidate all + redirects not working as expected.

[smblee]

Describe the bug

discord thread: https://discord.com/channels/457912077277855764/1020064864066093196

Hey all - I think i ran into a bug or unexpected behavior that i can't wrap my head around.

The app is structured so that the root / acts as a central "router" to determine current user's state and redirect them to appropriate landing pages.

The child pages also have their own redirection logic, and if user somehow got to the page directly, user is redirected back to the router /.

There is a notion of "profiles" and user can switch between the profiles using a switcher component (think AWS, switching between profiles with different permissions).

This component should
set the profile id in cookie from client side => invalidate/rerender the current page (client sided, via invalidateAll()) => if the current page has any redirection logic, redirect with new profile; if page can render with new profile, render with new data, etc.

The problem I am running into is, I call invalidateAll(), invalidation/rerunning nested layout code runs as expected (with the new profile id value), but at the very end of redirects, the profile id is seen as the previous value (which causes the "redirect loop" error, even when there really isn't a loop).

Reproduction

https://github.com/smblee/sveltekit-invalidate-all-bug

I reproduced it as close to my current repo as possible.

Say there are the following pages / (router, doesn't actually render), notset (ONLY when no profile set),signup (ONLY when profile is not-onboarded), onboarded-home (ONLY when profile is onboarded).

try going from Set not onboarded profile => Set onboarded profile or the other way around. (it will always fail on the first try, in one direction).

you will fail with the following log trace: (
it can seem a bit overwhelming, but it's pretty simple. I basically logged the location and current profile id value at that time in code. and any redirection that happens)

+layout |  not-onboarded-id
(student)/+layout |  not-onboarded-id
(student)/signup/+page |  not-onboarded-id
Selector.svelte:11 ---------------------------
Selector.svelte:12 SETTING PROFILE: START
Selector.svelte:13 prev: not-onboarded-id
Selector.svelte:14 expected: onboarded-id
Selector.svelte:17 SETTING PROFILE: SET COOKIE
Selector.svelte:18 cookie: profileId=onboarded-id
Selector.svelte:19 SETTING PROFILE: INVALIDATE ALL START
+layout |  onboarded-id
(student)/+layout |  onboarded-id
(student)/signup/+page |  onboarded-id
(student)/signup/+page | redirecting to /
Selector.svelte:21 SETTING PROFILE: INVALIDATE ALL ENDED
Selector.svelte:22 ---------------------------
+layout |  onboarded-id
+page |  onboarded-id
+page | redirecting to /onboarded-home
(student)/(onboarded)/+layout |  not-onboarded-id                   <------ should be `onboarded-id`
+(student)/(onboarded)/+layout | redirecting to /
+page |  not-onboarded-id                               <------ should be `onboarded-id`
+page | redirecting to /signup
+layout |  onboarded-id

Error: Redirect loop...

Logs

No response

System Info

System:
    OS: macOS 12.5
    CPU: (10) arm64 Apple M1 Pro
    Memory: 109.05 MB / 32.00 GB
    Shell: 5.8.1 - /bin/zsh
  Binaries:
    Node: 16.15.1 - ~/.nvm/versions/node/v16.15.1/bin/node
    npm: 8.11.0 - ~/.nvm/versions/node/v16.15.1/bin/npm
  Browsers:
    Chrome: 105.0.5195.125
    Safari: 15.6
  npmPackages:
    @sveltejs/adapter-auto: next => 1.0.0-next.75
    @sveltejs/kit: next => 1.0.0-next.483
    svelte: ^3.44.0 => 3.50.1
    vite: ^3.1.0 => 3.1.1

Severity

blocking an upgrade

Additional Information

No response

[smblee]

(going off of the log above) I think whats happening here is...

After the invalidation is completed, we are redirected to / (we have correct id here). Then / tries to redirect you to onboarded-home.

I think the expected behavior here is, in order to load onboarded-home, the app should get the data from the parents of this page (+layout => (student)/+layout => (student)/(onboarded)/+layout), but the log indicates you are going from +page directly to (student)/(onboarded)/+layout (skipping the first two layouts, getting stale data from before).

If the route isn't re-loaded from the root layout, we won't know there was a change when we get the data from await parent()

Current:

...
/+layout |  onboarded-id
/+page |  onboarded-id
/+page | redirecting to /onboarded-home
/(student)/(onboarded)/+layout |  not-onboarded-id                   <------ should be `onboarded-id`
/+(student)/(onboarded)/+layout | redirecting to /
/+page |  not-onboarded-id                               <------ should be `onboarded-id`
/+page | redirecting to /signup
/+layout |  onboarded-id

REDIRECT LOOP error :(

Expected?

...
/+layout |  onboarded-id
/+page |  onboarded-id
/+page | redirecting to /onboarded-home
+/+layout | onboarded-id
+/(student)/+layout | onboarded-id
-/(student)/(onboarded)/+layout |  not-onboarded-id                   <------ should be `onboarded-id`
+/(student)/(onboarded)/+layout |  onboarded-id
-/+(student)/(onboarded)/+layout | redirecting to /
-/+page |  not-onboarded-id                               <------ should be `onboarded-id`
-/+page | redirecting to /signup
-/+layout |  onboarded-id

-REDIRECT LOOP error :(
+You are at onboarded home!

[smblee]

ok i encountered this issue elsewhere again.

I think the problem is invalidateAll not causing all the layout load functions in the tree to run again, if you were redirected from another layout.
updateSomeData => invalidateAll() => throw redirect(...) due to the updated data => layout data state is out of sync in the redirected page

[j4w8n]

I ran across something similar. It took me a while to figure out what was going on. You may be seeing the same thing.

My issue is that when the invalidateAll runs, and loads start re-firing, throwing a redirect in one of them is like throwing an error; which I suspect interrupts the remaining load functions from re-firing or completing. Therefore no updated info in those areas.

Just the nature of throwing a redirect using sveltekit's method.

[smblee]

@j4w8n I also think it has to do with "redirects" being a throw messing up some invalidate tree traversal. Would help a lot if we can get some officia thoughts/usage around invalidate/invalidateAll/depends from the maintainers.