SerpApi Reference Architecture

Overview

Production architecture for search-powered applications using SerpApi. Core components: cached search service, multi-engine abstraction, SERP monitoring pipeline, and credit budget management.

Architecture Diagram

┌──────────────────────────────────┐
│          API Layer               │
│  /search  /track  /health        │
├──────────────────────────────────┤
│        Search Service            │
│  Multi-engine  Caching  Parsing  │
├──────────────────────────────────┤
│       SerpApi Client             │
│  Rate Limiting  Retry  Archive   │
├──────────────────────────────────┤
│       Infrastructure             │
│  Redis Cache  PostgreSQL  Cron   │
└──────────────────────────────────┘
         │
         ▼
┌──────────────────────────────────┐
│        SerpApi REST API          │
│  google  youtube  bing  news     │
│  1 credit/search, 100-50K/mo     │
└──────────────────────────────────┘

Project Structure

search-service/
├── src/
│   ├── serpapi/
│   │   ├── client.ts          # Cached search with rate limiting
│   │   ├── engines.ts         # Engine-specific param mapping
│   │   └── types.ts           # Typed result interfaces
│   ├── services/
│   │   ├── search.ts          # Multi-engine search facade
│   │   ├── tracking.ts        # Keyword rank tracking
│   │   └── credits.ts         # Usage monitoring
│   ├── api/
│   │   ├── search.ts          # /search proxy endpoint
│   │   └── health.ts          # /health with credit check
│   └── jobs/
│       └── rank-tracker.ts    # Daily keyword monitoring
├── tests/
│   ├── fixtures/              # Recorded SerpApi responses
│   └── search.test.ts         # Fixture-based tests
└── config/

Key Components

Search Service Facade

class SearchService {
  constructor(private client: CachedSerpApiClient, private db: Database) {}

  async search(query: string, options?: { engine?: string; num?: number }) {
    const engine = options?.engine || 'google';
    const result = await this.client.cachedSearch({
      engine, q: query, num: options?.num || 5,
    });

    // Normalize across engines
    return {
      results: result.organic_results || result.video_results || [],
      answer_box: result.answer_box || null,
      knowledge_graph: result.knowledge_graph || null,
      search_id: result.search_metadata.id,
      cached: result._cached || false,
    };
  }

  async trackKeyword(keyword: string, domain: string) {
    const result = await this.client.cachedSearch({
      engine: 'google', q: keyword, num: 100,
    });
    const position = result.organic_results?.findIndex(
      (r: any) => r.link?.includes(domain)
    );
    await this.db.saveRanking(keyword, domain, position >= 0 ? position + 1 : null);
  }
}

Credit Budget Manager

class CreditBudget {
  async check(): Promise<{ ok: boolean; remaining: number }> {
    const account = await fetch(
      `https://serpapi.com/account.json?api_key=${process.env.SERPAPI_API_KEY}`
    ).then(r => r.json());

    return {
      ok: account.plan_searches_left > 100,
      remaining: account.plan_searches_left,
    };
  }
}

Error Handling

Component	Failure	Recovery
Search API	Credits exhausted	Return cached results, alert ops
Cache	Redis down	Fall through to API (graceful degradation)
Rank tracker	Query fails	Skip and retry next cycle
Health check	API unreachable	Report degraded status

Resources

• SerpApi Documentation
• Searches Archive

Next Steps

See individual skill docs for deep-dives on each component.