Health Checks

~15 daq · NestJS · Ilg'or mavzular

Muammodan boshlaylik

Serveringiz ishlayapti — lekin ma'lumotlar bazasiga ulanolmayapti. Yoki Redis to'lib ketgan. Foydalanuvchilar xato ko'ryapti, lekin siz bilmayapsiz.

Docker yoki load balancer serveringiz "sog'lom" ekanini bilishi kerak. Agar sog'lom bo'lmasa — trafikni boshqa serverga yo'naltiradi yoki konteyner qayta ishga tushiriladi.

Buning uchun GET /health endpoint kerak.

Health Check nima?

Health Check — "server sog'lommi?" degan savolga javob beradigan endpoint.

Hayotiy o'xshatma

Tibbiy ko'rik. Shifokor tekshiradi: qon bosimi normal, yurak urishi yaxshi, o'pka tozami? Hammasi yaxshi — "sog'lom". Biror ko'rsatkich noto'g'ri — muammo bor.

Server uchun ham xuddi shunday: ma'lumotlar bazasi, Redis, disk bo'sh joy — barchasi tekshiriladi.

O'rnatish

npm install @nestjs/terminus
npm install @nestjs/axios axios

Fayl tuzilmasi

src/
  health/
    health.controller.ts  ← /health endpoint
    health.module.ts

Asosiy sozlash

// health/health.module.ts
import { Module } from '@nestjs/common';
import { TerminusModule } from '@nestjs/terminus';
import { HttpModule } from '@nestjs/axios';
import { HealthController } from './health.controller';

@Module({
  imports: [TerminusModule, HttpModule],
  controllers: [HealthController],
})
export class HealthModule {}

// health/health.controller.ts
import { Controller, Get } from '@nestjs/common';
import {
  HealthCheck,
  HealthCheckService,
  TypeOrmHealthIndicator,
  HttpHealthIndicator,
} from '@nestjs/terminus';

@Controller('health')
export class HealthController {
  constructor(
    private health: HealthCheckService,
    private db: TypeOrmHealthIndicator,
    private http: HttpHealthIndicator,
  ) {}

  @Get()
  @HealthCheck()
  check() {
    return this.health.check([
      () => this.db.pingCheck('database'),            // ← DB ulangan mi?
      () => this.http.pingCheck('google', 'https://google.com'), // ← internet bormi?
    ]);
  }
}

Natija

Hammasi yaxshi bo'lsa (HTTP 200):

{
  "status": "ok",
  "info": {
    "database": { "status": "up" },
    "google": { "status": "up" }
  }
}

Biror narsa ishlamasa (HTTP 503):

{
  "status": "error",
  "error": {
    "database": { "status": "down", "message": "Connection refused" }
  }
}

Disk va RAM tekshirish

import { DiskHealthIndicator, MemoryHealthIndicator } from '@nestjs/terminus';

@Controller('health')
export class HealthController {
  constructor(
    private health: HealthCheckService,
    private db: TypeOrmHealthIndicator,
    private disk: DiskHealthIndicator,
    private memory: MemoryHealthIndicator,
  ) {}

  @Get()
  @HealthCheck()
  check() {
    return this.health.check([
      () => this.db.pingCheck('database'),

      // Disk 90% dan ko'p to'lsa — xato
      () => this.disk.checkStorage('storage', { path: '/', thresholdPercent: 0.9 }),

      // RAM 300MB dan ko'p ishlatilsa — xato
      () => this.memory.checkHeap('memory', 300 * 1024 * 1024),
    ]);
  }
}

Nima uchun 503?

HTTP 503 "Service Unavailable" — server hozir ishlay olmaydi. Docker, load balancer va monitoring tizimlari aynan shu status kodni tekshiradi.

200 OK   → hammasi yaxshi, so'rovlarni yuboravering
503      → muammo bor, trafikni boshqa serverga yo'naltiring

Tez-tez uchraydigan xatolar

1. TypeORM indicator ishlamayapti

TypeOrmHealthIndicator provider not found

Sababi: TypeORM ishlatilmayapti yoki TypeOrmModule AppModule ga qo'shilmagan. Yechim: prisma.pingCheck() yoki mongoose.pingCheck() ishlatilsa — shunga mos indicator qo'ying.

2. HealthModule AppModule ga qo'shilmagan Yechim: app.module.ts imports ga HealthModule qo'shing.

Xulosa

• /health endpoint — server sog'lomligini ko'rsatadi
• 200 OK — hammasi yaxshi, 503 — muammo bor
• Database, disk, RAM, tashqi API — barchasini tekshirish mumkin
• Docker/monitoring tizimi shu endpointni tekshirib turadi

Keyingi dars: 47-dars: i18n — Internationalization