Agent-skills-standard nestjs-search

Integrate Elasticsearch and implement search index Sync patterns in NestJS. Use when integrating Elasticsearch or implementing search index sync in NestJS. (triggers: **/*.service.ts, **/search/**, Elasticsearch, CQRS, Synchronization)

install

source · Clone the upstream repo

git clone https://github.com/HoangNguyen0403/agent-skills-standard

Claude Code · Install into ~/.claude/skills/

T=$(mktemp -d) && git clone --depth=1 https://github.com/HoangNguyen0403/agent-skills-standard "$T" && mkdir -p ~/.claude/skills && cp -r "$T/skills/nestjs/nestjs-search" ~/.claude/skills/hoangnguyen0403-agent-skills-standard-nestjs-search && rm -rf "$T"

manifest: skills/nestjs/nestjs-search/SKILL.md

source content

Search Engine & Full-Text

Priority: P1 (OPERATIONAL)

Pattern: CQRS (Command Query Responsibility Segregation).
Write: To Primary Database (Postgres/MySQL). Source of Truth.
Read (Complex): To Search Engine (Elasticsearch, OpenSearch, MeiliSearch). Optimized for filtering, fuzzy search, and aggregation.

Synchronization ( Hard Part)

Dual Write (Anti-Pattern):
```
await db.save(); await es.index();
```
.
Why: Partial failures leave data inconsistent. Slows down HTTP response.
Event-Driven (Recommended):

Service writes to DB.
Service emits
```
EntityUpdated
```
.
Event Handler (Async) pushes to Queue (BullMQ).
Worker indexes document to Search Engine with retries.

CDC (Golden Standard): Change Data Capture (Debezium). Connects directly to DB transaction log. No app conceptual overhead, but higher ops complexity.

Organization

Module: Encapsulate client in
```
SearchModule
```
.
Abstraction: Create generic
```
SearchService<T>
```
helpers.
```
indexDocument(id, body)
```
```
search(query, filters)
```
Mapping: Use
```
class-transformer
```
to map Entities to "Search Documents". Keep docs flatter than relational entities.

Testing

E2E: not mock search engine in critical E2E flows.
Docker: Spin up
```
elasticsearch:8
```
container in test harness to verify indexing works.

Anti-Patterns

No dual writes to DB + ES: Use event-driven or CDC pattern; dual writes risk partial failure inconsistency.
No Elasticsearch for structured queries: Use DB indexes for filtering; ES for full-text and complex search.
No ES mocks in E2E search tests: Spin up
```
elasticsearch:8
```
container to verify indexing behavior accurately.