Files
deepseek-harness/docs/core-data-structures/settings.md
Yichen Jiang 1010291fe6 fix(settings): close cross-namespace, dispatch, and lifecycle races from second review
Confirmed and fixed, each with a regression test that failed first:

- Concurrent writes to different namespaces lost whole sections on disk
  (each persist rendered the full document from a stale text): the local
  provider serializes render->write->rename->text-commit on one internal
  persist chain shared by every namespace queue.
- One throwing settings/updated listener starved the rest (cordis emit
  stops at the first throw): commit fans out per listener via
  events.dispatch, contains individual failures, and rethrows the first
  INVARIANT-coded error only after every listener ran.
- Write queues ignored fiber/service lifecycle: the base init now
  registers a teardown that refuses new writes and drains queued chains;
  queued tasks re-verify service liveness and namespace ownership before
  running and again before committing, so a registrant disposed
  mid-flight is never notified and a disposed service never commits.
- Async watcher invocations could interleave (a slow stale call applied
  last): each watcher carries a serialized invocation chain — one call
  at a time, in commit order; JSDoc/doc pages state the async timing.
- update/replace borrowed the caller's object until the queued task ran:
  inputs are structured-clone snapshotted at call time; non-cloneable
  plain objects reject with a typed error.
- Composition guard now proves the documented fallback: the consumer
  uses the optional scoped-inject shape and boots both with the settings
  entry (hot publish) and without it (entry-config resolution, no scope).
- core-data-structures index: settings.md row added to the sub-page
  table in core.md/core.zh.md.

Both packages hold per-file 100% coverage across repeated runs.
2026-07-29 10:19:33 +08:00

4.3 KiB

User Settings

English | 中文

The user-settings seam of dsh-settings holds one user-owned document of per-namespace sections and resolves each registered namespace as schema defaults, then the registrant's composition base, then the user section. Providers such as dsh-settings-local store the raw document and push external edits; consumer plugins register a schema and read or observe the resolved value. Composition config stays in cordis.yml — a namespace carries only the user-editable subset.

Source: packages/settings/settings/src/index.ts

Identity

A namespace names one plugin-owned section of the user document. The brand keeps namespaces from mixing with other cross-boundary ids; construction validates the lowercase kebab-case shape.

/** Nominal id of one registered settings namespace. */
type SettingsNamespace = Branded<'SettingsNamespace'>

Registration

Registration binds a schemastery schema to a namespace on the calling plugin's fiber — disposing that fiber removes the namespace and its observers. The options carry the composition layer and the owner's effect timing.

/** Registration options beyond the namespace schema. */
interface SettingsRegisterOptions<T> {
  /** Composition-layer values resolved below the user layer (entry-config subset). */
  base?: Partial<T>
  /** Owner's effect timing, surfaced to configuration UIs; defaults to `live`. */
  applies?: SettingsApplies
}

applies is a UI hint, not a mechanism: a restart owner simply never watches, so its value is read once at construction and configuration surfaces can badge the pending change.

/** When a namespace's changes take effect for its owner. */
type SettingsApplies = 'live' | 'restart'

Owner scope

The scope is the owner-facing handle. update merges a sparse patch over the user section only (never into base); replace sets the section wholesale, which is the removal/reset path — keys absent from the replacement re-inherit base and schema defaults. Writes to one namespace are serialized in call order, and resolved values are deep-frozen snapshots.

/** Owner-facing handle for one registered namespace. */
interface SettingsScope<T> {
  /** Current resolved value: schema defaults, then `base`, then the user layer. */
  get(): T
  /**
   * Observe committed changes to this namespace's resolved value. Invocations
   * of one callback run asynchronously, one at a time, in commit order; a
   * rejection is contained and logged like a sync throw.
   * @param callback - invoked after each commit with the next and previous values.
   * @returns the disposer removing this observer.
   */
  watch(callback: (next: T, prev: T) => void | Promise<void>): () => void
  /**
   * Merge a partial patch into this namespace's user layer and persist it.
   * @param patch - plain-object patch over the user section.
   */
  update(patch: object): Promise<void>
  /**
   * Replace this namespace's user section wholesale; absent keys re-inherit
   * the composition `base` and schema defaults (`replace({})` resets all).
   * @param section - the complete next user section.
   */
  replace(section: object): Promise<void>
}

Descriptors

describe() serializes every registered namespace for configuration surfaces: the schemastery toJSON() envelope drives schema-rendered forms, and the resolved value fills them.

/** One registered namespace as surfaced to configuration UIs. */
interface SettingsDescriptor {
  /** The registered namespace. */
  ns: SettingsNamespace
  /** Serialized schemastery schema (`schema.toJSON()`). */
  schema: unknown
  /** Current resolved value. */
  value: unknown
  /** Owner's declared effect timing. */
  applies: SettingsApplies
}

Change commits

Every committed change — an in-process write or an externally observed provider edit — emits settings/updated (ns, next, prev, source) after the new value is authoritative, and never when the resolved value is deep-equal. The source tag separates the two entry paths.

/** Origin of one committed settings change. */
type SettingsUpdateSource = 'update' | 'provider'