Adapters

An adapter converts an input specification into the shared AST.

defineExtension

defineExtension with kind: 'adapter' takes a definition object and returns a factory that types the adapter's options. setup turns the user's options into the resolved options, and build returns the adapter's document, parse, and validate for them. Without setup, the user's options are the resolved options.

A minimal adapter declares a name and returns an empty InputNode. An empty AST emits nothing, so fill schemas and operations from your spec next.

import { ast, defineExtension } from 'kubb/kit'
import type { AdapterFactoryOptions } from 'kubb/kit'

type AdapterCustom = AdapterFactoryOptions<'adapter-custom', { strict?: boolean }, { strict: boolean }>

export const adapterCustom = defineExtension<AdapterCustom>({
  kind: 'adapter',
  meta: { name: 'adapter-custom' },
  setup: (options) => ({ strict: options.strict ?? false }),
  build: () => ({
    document: null,
    async parse(_source) {
      return ast.factory.createInput({ schemas: [], operations: [] })
    },
    async validate() {
      // Throw or call ctx.error here when the spec is invalid.
    },
  }),
})

createAdapter (deprecated)

createAdapter takes the same definition object as defineExtension, without kind. To move over, rename the call and add kind: 'adapter'. See Extensions.

Pass the adapter to your config:

import { defineConfig } from 'kubb/config'
import { adapterCustom } from './adapterCustom.ts'

export default defineConfig({
  input: './my-spec.json',
  output: { path: './src/gen' },
  adapter: adapterCustom({ strict: true }),
  plugins: [],
})

Adapter anatomy

Every adapter the factory returns matches the Adapter interface from kubb/kit:

Cross-references need no adapter hook: every plugin resolves $ref imports through resolver.imports, which defaults each ref to its pointer's last segment. An adapter that renames a schema (for example to break a name collision) stamps targetName on every ref node pointing at it, so those imports pick up the emitted name. Refs that keep their segment name need no stamp.

Adapter naming convention

Name adapters like plugins, so getResolver, the registry, and the docs can find them:

Export a satisfies-typed name constant so consumers can reuse the runtime name.