# Full Text Search

> Use for product search: FtsSearchRepo, pg_search/Elasticsearch, mapping migrations, projections, Outbox sync, reindexing and performance. Excludes agent web search.

- Skill: `lobehub/full-text-search` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add lobehub/full-text-search`
- Raw SKILL.md: https://api.skillmd.com/api/skills/lobehub/full-text-search/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: AI & ML
- Author: lobehub (https://skillmd.com/u/lobehub)
- Updated: 2026-09-09
- Page: https://skillmd.com/skills/lobehub/full-text-search

---


# Product Full-Text Search

This skill covers search over LobeHub-owned product data such as agents, topics, messages, files,
knowledge bases, documents, chat groups, and memories. It does not cover the agent's external web
search providers under `apps/server/src/services/search/` or builtin web-browsing tools.

## Architecture

Product reads follow one stable path:

```text
router/service -> createFtsSearchRepo -> FtsSearchRepo -> selected backend -> existing result schema
```

- `apps/server/src/services/ftsSearch/` owns request-scoped provider selection, Elasticsearch
  configuration, its HTTP client, and backend telemetry. Routers and domain services must call
  `createFtsSearchRepo`; they must not construct providers themselves.
- `packages/database/src/repositories/ftsSearch/` owns the provider-neutral contract and the concrete
  PostgreSQL and Elasticsearch implementations. Keep public result shapes stable in `FtsSearchRepo`.
- `packages/types/src/ftsSearch.ts` owns the shared searchable-entity list and search domain types.
- `packages/database/src/repositories/ftsSearchDocument/` owns Elasticsearch document schemas,
  mappings, queryable fields, and source-to-document projection.
- `packages/database/src/schemas/ftsSearchSyncOutbox.ts` and
  `packages/database/src/repositories/ftsSearchSyncOutbox/` own durable change capture, claims,
  retries, dead letters, leases, revision fences, and capture-definition validation.
- `scripts/elasticsearchReindex/` owns the resumable full-backfill command and its operational
  runtime. Shared database source queries and document construction remain in
  `packages/database/src/repositories/ftsSearchDocument/`. `apps/server/src/services/ftsSearchSync/` and
  `scripts/elasticsearchSync/` own continuous incremental draining.
- `packages/env/src/ftsSearch.ts` owns generic Elasticsearch environment variables.

## Provider and Permission Invariants

- `FTS_SEARCH_PROVIDER` is a deployment-level provider selector with current values `pg_search` and
  `elasticsearch`. It is not a feature flag or a user rollout. Add another enum value only when its
  provider is implemented end to end.
- Elasticsearch errors, missing configuration, and unsupported candidate behavior must remain
  visible. Never silently retry through PostgreSQL or add an `ilike` fallback.
- Before selecting Elasticsearch, require coverage tests proving that it supports every entity in
  the provider-neutral backend contract. Do not add per-entity routing between providers.
- Preserve `userId`, `workspaceId`, and caller-agent visibility throughout every provider. Candidate
  retrieval must not broaden the caller's scope.
- Where Elasticsearch only supplies candidate IDs, PostgreSQL hydration and parent checks remain
  the authoritative permission boundary. Do not return raw Elasticsearch hits directly when the
  existing result path requires database authorization or hydration.
- Provider implementations return the existing hydrated response types and ordering contract. Do
  not make routers understand provider-specific result shapes.

## Changing a Searchable Entity

Treat an entity addition or projection change as one cross-layer change. Inspect and update every
applicable item:

1. `FTS_SEARCH_DOCUMENT_ENTITIES` and shared request/result types.
2. Search document schema, mapping, text fields, filters, fixtures, and mapping parity tests.
3. `FtsSearchDocumentBuilder`, including soft deletion and fanout from related source rows.
4. PostgreSQL and Elasticsearch backend behavior, permission hydration, pagination, and ranking.
5. Capture functions/triggers or fanout queries in `captureInfrastructure.ts`.
6. Reindex checkpoints, Outbox draining, metrics, and self-host documentation.

Schema fields, mappings, builders, and fixed fixtures must agree. Current mapping fields plus
explicit `FTS_SEARCH_RETAINED_SOURCE_PROPERTIES` must equal the current Zod fields, without overlap.
Retained source properties keep older open indexes writable during field removals; keep the builder
producing them until those indexes are closed. They must not appear in current query metadata.
A field outside the document schema must not appear in a mapping or query field list.

Elasticsearch `multi_match` query length is bounded by a shared leaf-clause budget divided by the
selected query-field count. Adding a field reduces that entity's safe query length, and changing a
query analyzer to emit multiple terms per Unicode code point requires revisiting the budget and its
field-count regression tests.

## Capture, Reindex, and Sync

- Regular database migrations own durable schema: the revision sequence, Outbox table and indexes,
  and schema-managed source indexes such as the Memory fanout GIN index.
- Capture functions and triggers are installed only when an operator explicitly enables the
  Elasticsearch path. `installCaptureInfrastructure()` is transactional, definition-checked,
  idempotent for an exact installation, and fail-closed for partial or altered definitions.
- Do not install capture for every PostgreSQL-only instance. Do not move a normal schema index into
  the runtime installer merely because it supports capture.
- The Outbox coalesces by `(entity, document_id)`. A newer capture resets retry/dead-letter state and
  allocates a new revision only after locking the conflicting row, preserving same-document commit
  order.
- Sequence allocation is non-transactional. Use the existing write fences and committed revision
  boundary; never treat `last_value` alone as proof that all earlier Outbox rows are visible.
- Claims use the precise lease timestamp as a fencing token. A stale worker must not acknowledge,
  fail, or release work reclaimed by another worker.
- Permanent failures and exhausted retries become durable dead letters. A drain that creates or
  observes dead work must fail instead of continuing to publish a successful cutover signal.
- Full backfill does not replace continuous sync. For the initial PostgreSQL-to-Elasticsearch
  cutover, keep the application on PostgreSQL until aliases are ready and the Outbox is empty and
  stable, then switch explicitly. Later mapping upgrades keep searches on the existing Elasticsearch
  alias until promotion.

The supported operator entrypoints below run from the OSS repository root. A wrapping repository
may expose different package scripts; check its `package.json` before invoking these or the mapping
migration commands linked below.

```bash
bun run db:install-fts-search-capture
bun run fts-search:reindex -- --status
bun run fts-search:reindex -- --apply --yes
bun run fts-search:sync -- --max-steps=8 --yes
bun run scripts/pgSearchCleanup/index.ts --status
bun run scripts/pgSearchCleanup/index.ts --apply --yes
```

## Mapping Generations

Docker startup runs `fts-search-elasticsearch-reindex.cjs --startup --yes` after PostgreSQL
migrations when the selected provider is Elasticsearch. It blocks serving until index migration
and catch-up succeed. Persist the same checkpoint volume across application and migration
containers; failed namespace locks still require explicit recovery. Continuous sync remains a
separate worker. Hosted and manual workflows keep their explicit migration commands.

For mapping changes, generation operations, repeat/resume behavior, or deployment integration, read
[Mapping migration workflow](references/mapping-migrations.md). It routes to the public command guide
and adds recovery, automation, and local Docker rehearsal rules.

Elasticsearch cannot change an existing field's type or index-time analyzer in place. The code
declares the target and Elasticsearch records the live state, per entity:

- `FTS_SEARCH_INDEX_DEFINITIONS[entity].schemaVersion` is the declared generation; the fingerprint is
  `sha256` of the mapping plus the shared analysis. Add complete changed-entity definitions in a new
  `ftsSearchDocument/migration/NNNN-meaningful-name/` batch, register it and update current pointers
  in `migration/index.ts`. Append expected fingerprints in `__tests__/schemaSnapshots.json`; preserve
  published batches and baselines. `mappings.test.ts` and `migration/index.test.ts` check current
  parity, history, version bumps and fingerprint changes. See `migration/README.md` for ownership.
  Shared analysis changes alter
  every entity fingerprint and classify as breaking for every entity; bump all affected versions
  and rebuild rather than using in-place upgrades.
- Every physical index `<alias>-v<n>` carries `_meta.{reindex_run_id, schema_version,
schema_fingerprint}`; the alias marks the live generation. Indexes created before fingerprints
  existed may omit the fingerprint, but still need a valid run ID and schema version for sync
  readiness. `_meta.schema_version` wins over the `-v<n>` suffix because an in-place upgrade advances
  `_meta` without renaming the index.
- The sync runtime accepts an alias that still serves an older generation (upgrade in progress) and
  refuses one that serves a newer generation or a different fingerprint of the declared version. It
  writes every change to all open `<alias>-v*` indexes plus the alias write index, pruning each
  document to the fields that index maps (every generation is `dynamic: strict`), so a new
  generation can be backfilled beside the live one; a bulk work item is acknowledged only when
  every existing generation accepted it (2xx or 409 conflict).
- One reindex checkpoint per `(namespace, schemaVersion)` covers the entities on that generation.
  `--apply` groups the requested entities by declared version, treats existing aliases as an
  upgrade (no `--fresh-run`), leaves existing aliases in place, and emits `promotion_pending`. A
  completed first install creates aliases. Promoting a newer generation requires a completed
  checkpoint, a fingerprint match when targeting the declared version, and an idle target-entity Outbox. Rollback
  to an older stamped generation can use its metadata without a retained checkpoint;
  `--retire` requires `in_sync` and only closes old generations; explicit `--purge` installs
  exact-index templates forbidding auto-creation before deleting eligible closed generations.
  `--in-place` requires
  `mappingChange: additive`, widens the live index with `PUT _mapping`, pins the checkpoint to that
  index, and backfills with `external_gte` so concurrent sync writes win.
- Checkpoints are local files, not Drizzle migration history. Preserve `ES_REINDEX_STATE_DIR` across
  invocations. Completed runs skip backfill; incomplete runs resume from saved cursors. Mutating CLI
  commands share a non-expiring Elasticsearch namespace lock, independent of checkpoint location.
  A failed command retains its lock when its outcome may be uncertain. Before `--release-lock=<owner> --yes`, stop the previous process and resolve pending requests; never assume age proves it stopped.
  The lock does not serialize old binaries or external operator actions.
- Reconciliation is exact only on a first install; once an alias serves an entity, concurrent sync
  writes make a higher Elasticsearch count legitimate and only a shortfall fails.
- `scripts/elasticsearchReindex/runtime/generationService.ts` owns classification (`missing`,
  `unmanaged`, `in_sync`, `drift`, `upgrade_available`, `rollback_required`), promotion, and
  retirement; keep them free of Cloud-specific policy.

Read `docs/self-hosting/advanced/elasticsearch-migration.mdx` or its Chinese counterpart before
changing the operational sequence. When database rollout or index cost affects the design, also
use the `db-migrations` skill and measure the relevant operation on the actual Dev database before
adding manual or deferred release steps.

## Observability and Product Analytics

- Server provider metrics and traces live in `apps/server/src/services/ftsSearch/observability.ts`.
  Keep labels bounded: entity, provider, operation, outcome, and coarse error type are acceptable;
  raw queries, user IDs, document IDs, and index contents are not.
- User-perceived search behavior lives with the open-source Command Menu in
  `src/features/CommandMenu/analytics.ts`. Product analytics may cover end-to-end duration, rendered
  result counts, empty results, result clicks, and abandonment without a Cloud business slot.
- Measurement or analytics failures must never alter the selected provider's result or error.
- Backend metrics explain provider cost and latency; frontend events explain what the user actually
  experienced. Do not substitute one for the other.

## Validation

- Add or update focused tests beside every changed provider, mapping, builder, capture, sync, or
  analytics module.
- Preserve boundary tests proving callers use `FtsSearchRepo`, providers cannot leak raw result shapes,
  and telemetry failures do not affect search behavior.
- Test pagination after authorization drops candidates, delete/scope-change priority, concurrent
  Outbox claims and stale settlements, retry/dead-letter behavior, reindex resume identity, and
  capture-definition mismatch whenever those paths change.
- Run `bun run check <changed-files...>` from the repository root. For migration or database-runtime
  changes, follow the `db-migrations` and `testing` skills and verify against the actual Dev database.

