Context

To support enumStyle (#5223), we need to upgrade oazapfts from v6 to v7. However, v7 removes the ApiGenerator class and oazapfts/generate export path entirely — the semi-official APIs that codegen currently depends on. The new public API is limited to createContext (oazapfts/context), UNSTABLE_cg, and generateAst (oazapfts).

In #4265, @Xiphe notified that v7 would remove these APIs, and a Plugin System is in early development (oazapfts#805).

Migration options

Option A: Reimplement lazy type generation locally

Compatibility adapter (~400 lines) using v7's createContext + UNSTABLE_cg, reimplementing the removed ApiGenerator behavior.

• Pro: Preserves v6's lazy architecture — types are created on-demand per $ref, so filterEndpoints works naturally.
• Con: ~400 lines of type generation logic that needs manual sync when oazapfts evolves.

Option B: Use generateAst + post-filter unreferenced types

Use v7's generateAst(ctx) to generate all types upfront, then filter out types not referenced by selected endpoints.

• Pro: Delegates type generation to oazapfts — bug fixes and new features are inherited automatically.
• Con: Requires AST-based transitive closure to determine referenced types. Circular references and discriminator patterns make this non-trivial.

Proof of concept

I have a working implementation of Option A that passes all 73 existing tests, including enumStyle: 'union' | 'enum' | 'as-const' support and proper handling of discriminator patterns, readOnly/writeOnly, and unionUndefined. Happy to share as a draft PR, or pivot to another approach.

Questions

1. Which migration approach is preferred? Option A is ready now but adds maintenance; Option B delegates more but requires filter logic. Or should we wait for the Plugin System (Oazapfts will get plugins #4265) instead?
2. Is it worth coordinating with @Xiphe on what RTK codegen would need from the plugin API?
3. Should the v7 migration be a separate PR from enumStyle? The migration is a prerequisite, but splitting might make review easier.

Related

• feat(codegen): Expose enumStyle option from oazapfts v7.3.0 #5223 — enumStyle feature request
• Oazapfts will get plugins #4265 — oazapfts Plugin System notification (maintainer discussion)
• Update oazapfts to 6.1 #4588 — Previous oazapfts update (v6.1)
• oazapfts#805 — Plugin System PR
• oazapfts#823 — enumStyle in oazapfts