feat(ipx): support nuxt layers

[Aareksio]

Issue: #940

The issue is caused by IPX receiving only the root public directory. IPX's node-fs storage does not support multiple directories. I've migrated to unstorage (as per TODO left in comment. Next I implemented combine driver which combines multiple unstorage storages, at least the parts which gets used by IPX.

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Considerations

1. The performance of combine driver is probably a bit worse than if it was all single storage, but I do not think this is a big issue considering it gets enabled only in dev, when using layers with public assets. And even then, I do not think any degradation would be noticeable with sane number of images.

2. Please notice unstorage added to devDependencies. I am unsure where it belongs. ipx is devDependency and is marked as external in build.config.ts. But I never had to install ipx separately when adding @nuxt/image, not quite sure how it works.

3. IPXRuntimeConfig has changed. Please check if it makes sense. The is only one fs-lite driver option that could be exposed (ignore). As the directory is supposed to be deployed (public), I do not think there is a point in allowing @nuxt/image user configuring underlying storage solution. Ignoring should be either dealt on module level or IPX. Not in provider configuration.

4. I find the image.dir module option weird in context of ipx code. In module.ts we resolve it to absolute path, but later in ipx.ts we resolve it again...? This also makes it impossible to resolve against layers. Docs have 3 notes explaining contexts the option does not work. Maybe it is a good idea to remove it and just recommend people to stick to public?

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@pi0 I could not figure out how to use unstorageToIPXStorage from unstorage. It requires prefix and does not translate / to : in path, making it unusable. It is probably a good idea to update unstorage with proper implementation and remove the makeshift one from here. Also a proper built-in combine utility, or node-fs-multiple driver would have helped a lot.

[Aareksio]

@pi0 Migratated the PR to use unjs/ipx#203. Tested locally with ipx@2.1.0, I did not want to update deps as part of feature, assuming they gonna be bumped independently. I've also tried to mimic the style from your commits on my other PRs, minimal diff, helper functions after main one, do not break logic if not necessary. Hope it fits your vision :)

Also kept the TODO comment, since we reverted back to ipx's fs driver.

[pi0]

Amazing thanks for efforts. Will double check in the meantime feel free to bump dep in same PR should be fine.

[codecov-commenter]

Codecov Report

Attention: 5 lines in your changes are missing coverage. Please review.

Comparison is base (05621b8) 68.90% compared to head (81359d9) 69.01%.

Files	Patch %	Lines
src/ipx.ts	82.60%	4 Missing ⚠️
src/runtime/ipx.ts	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1177      +/-   ##
==========================================
+ Coverage   68.90%   69.01%   +0.10%     
==========================================
  Files          75       75              
  Lines        4245     4266      +21     
  Branches      393      399       +6     
==========================================
+ Hits         2925     2944      +19     
- Misses       1293     1295       +2     
  Partials       27       27              

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[danielroe]

Amazing ❤️ 🔥

[Aareksio]

Sorry for not pushing the update myself, got caught in other work 😅

[danielroe]

Not to worry! This is a great improvement. ❤️

[pi0]

Other than two above comments looks nice thanks for helping on this ❤️