feat: environment api

[patak-dev]

Description

Important

The Environment API work has been consolidated into #16471

Work in progress implementation of the design outlined at:

• docs: environment API proposal #16089

Some of the changes that need to happen:

• Separate module graphs per environments
• Backward compatible mixed server.moduleGraph
• Pass Environment { id, type, config } instead of string
• Move moduleGraph.safeModulePaths to server.safeModulePaths
• Rework ssrFixStacktrace, maybe it isn't needed anymore
• Properly implement the new environment aware hotUpdate hook
• Move transformRequest et al to the environment
• Move server.hot to the environment
• Rework Vite Runtime API as ModuleRunner
• Fine-grained HMR-updates per environment
• Environment config overrides
• Backward compat for config changes
• Environments registration
• Abstract ssrEnvironment
• Move getDepsOptimizer to environment
• workerd environment prototype against this PR

To be implemented in future PRs:

• Delete ssrError and ssrModule once ssrLoadModule is using the new APIs
• Explore environment aware vite build
• Explore RPC layer in core run vs import
• Dynamic version of the apply option

We can keep improving and discussing the spec in #16089 and later on merge it as the docs PR for this feature. Sending this PR so we have a branch were we can collaborate in the implementation.

The starting point for this PR is a squash of:

• feat: separate module graphs per environment #16003

#16003 implements the separation of the module graphs for the browser and server environments. Internal plugins in Vite have been refactored to use the independent module graphs. A backward compatibility later has been implemented so server.moduleGraph works for downstream projects in the ecosystem. Only Nuxt and Astro are failing right now in vite-ecosystem-ci for it. We can keep working on fixing backward compatibility in that PR and then merge the fixes here.

So far, I moved the the each EnvironmentModuleGraph inside of ModuleExecutionEnvironment.
Some decisions that diverge from the current spec and we still need to discuss (there or here):

• There is only a server.environments: Map<string, ModuleExecutionEnvironment> for now. The code is using server.environments.get(environmentId)
• A ModuleExecutionEnvironment has an id that is unique for the server, and a type. The idea here is to allow for several dev environments of the same type (like workerd) to be used at the same time.
• We may want to rediscuss nodeEnvironment being called node. If at one point the Vite dev server may be run in a non-node environment, the name may not be the best. Imagine if the landscape evolves into us wanting to use only a standard subset that works in more environments for Vite core. I don't know a better name though, serverEnvironment (as in "the same environment as the server") doesn't work that well either.

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What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

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[sheremet-va]

Can we guarantee it exists somehow? (non undefined)

[patak-dev]

The problem is that during scan, we didn't pass the moduleGraph. See here

vite/packages/vite/src/node/optimizer/scan.ts

Line 212 in d2839bc

const container = await createPluginContainer(config)

So I didn't pass the environment either. I thought that it may make the scan slower if we need to update info in a module graph that we are going to throw away. But I think it is wrong that we don't pass an environment, more once we will have environment specific config. I'll check what needs to be done here. I think we only need the plugins for resolveId that shouldn't mess with the moduleGraph, so maybe we can create a new temporal browser environment with a new module graph and pass that. I'll check this out, it would be a lot better if there is always an environment defined.

[patak-dev]

Let's see if there isn't some internalish use cases of these hooks in the ecosystem, but for now, core works with options and environment being required for hooks. See e30b858

I fixed some issues were I missed passing the environment, so even if we revert, it was worth it. We currently have a design issue because an environment needs a resolveId function when it is created, that should be implemented as container.resolveId(id, undefined, { environment }). I'll rework this next so we can simplify the code. Edit: done in 03d3889

[patak-dev]

It seems we'll need to relax the types. See failing test for Vitest. We could leave them as is for a bit more if they help us work with this draft though.

[patak-dev]

I already moved back to optional options and environment. If not, we were forced to have a new GlobalEnvironment that would be used when we don't have a server available (in the plugin containers created during config resolution for example).
Still, this was quite helpful to identify issues. And things looks better after fcebb7d

[vite-ecosystem-ci]

📝 Ran ecosystem CI on f927702: Open

suite	result	latest scheduled
astro	❌ failure	✅ success
nuxt	❌ failure	✅ success
vike	❌ failure	✅ success
vite-plugin-svelte	❌ failure	✅ success

✅ analogjs, histoire, ladle, laravel, marko, previewjs, qwik, rakkas, sveltekit, unocss, vite-plugin-pwa, vite-plugin-react, vite-plugin-react-pages, vite-plugin-react-swc, vite-plugin-vue, vite-setup-catalogue, vitepress, vitest