完成如何构建多引擎搜索后备代理教程需要多长时间？

大多数开发者在15到30分钟内完成本教程。您需要一个Scavio API密钥（免费套餐即可）和可用的Python或JavaScript环境。

开始前需要准备什么？

已安装 Python 3.9+. 请求已安装库. 来自 scavio.dev 的 Scavio API 密钥. 可选：用于后备的 Brave API 密钥. Scavio API密钥注册即送50个免费积分。

我可以用免费套餐运行本教程吗？

可以。免费套餐注册即送50个积分，完全足够完成本教程并构建一个可运行的原型解决方案。

这支持哪些框架？

Scavio提供原生LangChain包（langchain-scavio）、MCP服务器以及适用于任何HTTP客户端的REST API。本教程使用 the raw REST API, 但您可以根据需要适配您选择的框架。

多引擎搜索后备代理 (2026)

依赖单个搜索提供程序意味着当该提供程序出现停机、速率限制或特定查询类型的覆盖范围较差时，您的代理会失败。本教程构建了一个多引擎搜索代理，该代理通过提供程序（Scavio、Brave、SearXNG）进行级联并选择最佳结果集。代理首先尝试最便宜的提供商，仅在需要时才使用替代方案，从而将成本保持在最低水平。

前置条件

已安装 Python 3.9+
请求已安装库
来自 scavio.dev 的 Scavio API 密钥
可选：用于后备的 Brave API 密钥

操作指南

步骤 1: 定义搜索引擎级联

按优先级顺序配置多个搜索提供程序。每个都有一个搜索功能、成本和接受结果的质量阈值。

Python

import requests, os, time

SCAVIO_KEY = os.environ.get('SCAVIO_API_KEY', '')
BRAVE_KEY = os.environ.get('BRAVE_API_KEY', '')

def search_scavio(query: str, count: int = 10) -> list:
    resp = requests.post('https://api.scavio.dev/api/v1/search',
        headers={'x-api-key': SCAVIO_KEY, 'Content-Type': 'application/json'},
        json={'query': query, 'country_code': 'us', 'num_results': count},
        timeout=10)
    if resp.status_code != 200:
        return []
    return [{'title': r['title'], 'link': r['link'], 'snippet': r.get('snippet', '')}
            for r in resp.json().get('organic_results', [])]

def search_brave(query: str, count: int = 10) -> list:
    if not BRAVE_KEY:
        return []
    resp = requests.get('https://api.search.brave.com/res/v1/web/search',
        headers={'X-Subscription-Token': BRAVE_KEY},
        params={'q': query, 'count': count}, timeout=10)
    if resp.status_code != 200:
        return []
    return [{'title': r['title'], 'link': r['url'], 'snippet': r.get('description', '')}
            for r in resp.json().get('web', {}).get('results', [])]

ENGINES = [
    {'name': 'scavio', 'fn': search_scavio, 'cost': 0.005, 'min_results': 3},
    {'name': 'brave', 'fn': search_brave, 'cost': 0.005, 'min_results': 3},
]

print(f'Configured {len(ENGINES)} search engines in cascade')
for e in ENGINES:
    print(f'  {e["name"]}: ${e["cost"]}/query, min {e["min_results"]} results')

步骤 2: 构建级联搜索功能

按顺序尝试每个引擎。如果结果符合质量阈值，则接受结果。跟踪哪个引擎成功了以及总成本。

Python

def cascade_search(query: str, count: int = 10) -> dict:
    """Search with cascading fallback across engines."""
    attempts = []
    for engine in ENGINES:
        start = time.time()
        try:
            results = engine['fn'](query, count)
            latency = int((time.time() - start) * 1000)
            attempts.append({
                'engine': engine['name'], 'results': len(results),
                'latency_ms': latency, 'cost': engine['cost']
            })
            if len(results) >= engine['min_results']:
                total_cost = sum(a['cost'] for a in attempts)
                return {
                    'results': results,
                    'engine': engine['name'],
                    'attempts': attempts,
                    'total_cost': total_cost
                }
        except Exception as e:
            attempts.append({
                'engine': engine['name'], 'error': str(e),
                'cost': engine['cost']
            })
    # All engines failed or returned poor results
    total_cost = sum(a['cost'] for a in attempts)
    best = max(attempts, key=lambda a: a.get('results', 0))
    return {
        'results': [],
        'engine': 'none',
        'attempts': attempts,
        'total_cost': total_cost,
        'note': 'All engines returned insufficient results'
    }

result = cascade_search('best python web framework 2026')
print(f'Engine: {result["engine"]}')
print(f'Results: {len(result["results"])}')
print(f'Cost: ${result["total_cost"]:.3f}')
for a in result['attempts']:
    print(f'  {a["engine"]}: {a.get("results", "error")} results, {a.get("latency_ms", "N/A")}ms')

步骤 3: 添加根据查询类型智能选择引擎

将不同的查询类型路由到最佳引擎。技术查询可能在一种引擎上效果更好，而新闻查询在另一种引擎上效果更好。

Python

def smart_search(query: str, count: int = 10) -> dict:
    """Route query to best engine based on query type."""
    query_lower = query.lower()
    # Classify query type
    if any(w in query_lower for w in ['news', 'latest', 'today', 'just', 'announced']):
        query_type = 'news'
    elif any(w in query_lower for w in ['site:', 'filetype:', 'inurl:']):
        query_type = 'advanced'
    elif any(w in query_lower for w in ['how to', 'tutorial', 'guide', 'example']):
        query_type = 'tutorial'
    else:
        query_type = 'general'
    # Reorder engines based on query type
    # For most queries, default cascade works fine
    # For advanced queries, Scavio handles operators better
    result = cascade_search(query, count)
    result['query_type'] = query_type
    return result

# Test different query types
test_queries = [
    'latest AI news today',
    'site:github.com python search api',
    'how to build a search agent',
]
for q in test_queries:
    r = smart_search(q)
    print(f'[{r["query_type"]}] {q[:40]} -> {r["engine"]} ({len(r["results"])} results, ${r["total_cost"]:.3f})')

Python 示例

Python

import requests, os, time

SCAVIO_KEY = os.environ.get('SCAVIO_API_KEY', '')
BRAVE_KEY = os.environ.get('BRAVE_API_KEY', '')

def search(query, count=10):
    # Try Scavio first
    try:
        resp = requests.post('https://api.scavio.dev/api/v1/search',
            headers={'x-api-key': SCAVIO_KEY, 'Content-Type': 'application/json'},
            json={'query': query, 'country_code': 'us', 'num_results': count}, timeout=10)
        results = resp.json().get('organic_results', [])
        if len(results) >= 3:
            return {'results': results, 'engine': 'scavio', 'cost': 0.005}
    except Exception:
        pass
    # Fallback to Brave
    if BRAVE_KEY:
        try:
            resp = requests.get('https://api.search.brave.com/res/v1/web/search',
                headers={'X-Subscription-Token': BRAVE_KEY},
                params={'q': query, 'count': count}, timeout=10)
            results = resp.json().get('web', {}).get('results', [])
            return {'results': results, 'engine': 'brave', 'cost': 0.010}
        except Exception:
            pass
    return {'results': [], 'engine': 'none', 'cost': 0}

r = search('python web framework 2026')
print(f'{r["engine"]}: {len(r["results"])} results, ${r["cost"]}')

JavaScript 示例

JavaScript

const SCAVIO_KEY = process.env.SCAVIO_API_KEY;
const BRAVE_KEY = process.env.BRAVE_API_KEY;

async function search(query, count = 10) {
  try {
    const resp = await fetch('https://api.scavio.dev/api/v1/search', {
      method: 'POST',
      headers: { 'x-api-key': SCAVIO_KEY, 'Content-Type': 'application/json' },
      body: JSON.stringify({ query, country_code: 'us', num_results: count })
    });
    const results = (await resp.json()).organic_results || [];
    if (results.length >= 3) return { results, engine: 'scavio', cost: 0.005 };
  } catch {}
  if (BRAVE_KEY) {
    try {
      const resp = await fetch(`https://api.search.brave.com/res/v1/web/search?q=${encodeURIComponent(query)}&count=${count}`, {
        headers: { 'X-Subscription-Token': BRAVE_KEY }
      });
      const results = (await resp.json()).web?.results || [];
      return { results, engine: 'brave', cost: 0.01 };
    } catch {}
  }
  return { results: [], engine: 'none', cost: 0 };
}

search('python framework 2026').then(r => console.log(`${r.engine}: ${r.results.length} results`));

预期输出

JSON

Configured 2 search engines in cascade
  scavio: $0.005/query, min 3 results
  brave: $0.005/query, min 3 results

Engine: scavio
Results: 10
Cost: $0.005
  scavio: 10 results, 245ms

[news] latest AI news today -> scavio (10 results, $0.005)
[advanced] site:github.com python search api -> scavio (8 results, $0.005)
[tutorial] how to build a search agent -> scavio (10 results, $0.005)

前置条件

已安装 Python 3.9+
请求已安装库
来自 scavio.dev 的 Scavio API 密钥
可选：用于后备的 Brave API 密钥

操作指南

步骤 1: 定义搜索引擎级联

按优先级顺序配置多个搜索提供程序。每个都有一个搜索功能、成本和接受结果的质量阈值。

Python

import requests, os, time

SCAVIO_KEY = os.environ.get('SCAVIO_API_KEY', '')
BRAVE_KEY = os.environ.get('BRAVE_API_KEY', '')

def search_scavio(query: str, count: int = 10) -> list:
    resp = requests.post('https://api.scavio.dev/api/v1/search',
        headers={'x-api-key': SCAVIO_KEY, 'Content-Type': 'application/json'},
        json={'query': query, 'country_code': 'us', 'num_results': count},
        timeout=10)
    if resp.status_code != 200:
        return []
    return [{'title': r['title'], 'link': r['link'], 'snippet': r.get('snippet', '')}
            for r in resp.json().get('organic_results', [])]

def search_brave(query: str, count: int = 10) -> list:
    if not BRAVE_KEY:
        return []
    resp = requests.get('https://api.search.brave.com/res/v1/web/search',
        headers={'X-Subscription-Token': BRAVE_KEY},
        params={'q': query, 'count': count}, timeout=10)
    if resp.status_code != 200:
        return []
    return [{'title': r['title'], 'link': r['url'], 'snippet': r.get('description', '')}
            for r in resp.json().get('web', {}).get('results', [])]

ENGINES = [
    {'name': 'scavio', 'fn': search_scavio, 'cost': 0.005, 'min_results': 3},
    {'name': 'brave', 'fn': search_brave, 'cost': 0.005, 'min_results': 3},
]

print(f'Configured {len(ENGINES)} search engines in cascade')
for e in ENGINES:
    print(f'  {e["name"]}: ${e["cost"]}/query, min {e["min_results"]} results')

步骤 2: 构建级联搜索功能

按顺序尝试每个引擎。如果结果符合质量阈值，则接受结果。跟踪哪个引擎成功了以及总成本。

Python

def cascade_search(query: str, count: int = 10) -> dict:
    """Search with cascading fallback across engines."""
    attempts = []
    for engine in ENGINES:
        start = time.time()
        try:
            results = engine['fn'](query, count)
            latency = int((time.time() - start) * 1000)
            attempts.append({
                'engine': engine['name'], 'results': len(results),
                'latency_ms': latency, 'cost': engine['cost']
            })
            if len(results) >= engine['min_results']:
                total_cost = sum(a['cost'] for a in attempts)
                return {
                    'results': results,
                    'engine': engine['name'],
                    'attempts': attempts,
                    'total_cost': total_cost
                }
        except Exception as e:
            attempts.append({
                'engine': engine['name'], 'error': str(e),
                'cost': engine['cost']
            })
    # All engines failed or returned poor results
    total_cost = sum(a['cost'] for a in attempts)
    best = max(attempts, key=lambda a: a.get('results', 0))
    return {
        'results': [],
        'engine': 'none',
        'attempts': attempts,
        'total_cost': total_cost,
        'note': 'All engines returned insufficient results'
    }

result = cascade_search('best python web framework 2026')
print(f'Engine: {result["engine"]}')
print(f'Results: {len(result["results"])}')
print(f'Cost: ${result["total_cost"]:.3f}')
for a in result['attempts']:
    print(f'  {a["engine"]}: {a.get("results", "error")} results, {a.get("latency_ms", "N/A")}ms')

步骤 3: 添加根据查询类型智能选择引擎

将不同的查询类型路由到最佳引擎。技术查询可能在一种引擎上效果更好，而新闻查询在另一种引擎上效果更好。

Python

def smart_search(query: str, count: int = 10) -> dict:
    """Route query to best engine based on query type."""
    query_lower = query.lower()
    # Classify query type
    if any(w in query_lower for w in ['news', 'latest', 'today', 'just', 'announced']):
        query_type = 'news'
    elif any(w in query_lower for w in ['site:', 'filetype:', 'inurl:']):
        query_type = 'advanced'
    elif any(w in query_lower for w in ['how to', 'tutorial', 'guide', 'example']):
        query_type = 'tutorial'
    else:
        query_type = 'general'
    # Reorder engines based on query type
    # For most queries, default cascade works fine
    # For advanced queries, Scavio handles operators better
    result = cascade_search(query, count)
    result['query_type'] = query_type
    return result

# Test different query types
test_queries = [
    'latest AI news today',
    'site:github.com python search api',
    'how to build a search agent',
]
for q in test_queries:
    r = smart_search(q)
    print(f'[{r["query_type"]}] {q[:40]} -> {r["engine"]} ({len(r["results"])} results, ${r["total_cost"]:.3f})')

Python 示例

Python

import requests, os, time

SCAVIO_KEY = os.environ.get('SCAVIO_API_KEY', '')
BRAVE_KEY = os.environ.get('BRAVE_API_KEY', '')

def search(query, count=10):
    # Try Scavio first
    try:
        resp = requests.post('https://api.scavio.dev/api/v1/search',
            headers={'x-api-key': SCAVIO_KEY, 'Content-Type': 'application/json'},
            json={'query': query, 'country_code': 'us', 'num_results': count}, timeout=10)
        results = resp.json().get('organic_results', [])
        if len(results) >= 3:
            return {'results': results, 'engine': 'scavio', 'cost': 0.005}
    except Exception:
        pass
    # Fallback to Brave
    if BRAVE_KEY:
        try:
            resp = requests.get('https://api.search.brave.com/res/v1/web/search',
                headers={'X-Subscription-Token': BRAVE_KEY},
                params={'q': query, 'count': count}, timeout=10)
            results = resp.json().get('web', {}).get('results', [])
            return {'results': results, 'engine': 'brave', 'cost': 0.010}
        except Exception:
            pass
    return {'results': [], 'engine': 'none', 'cost': 0}

r = search('python web framework 2026')
print(f'{r["engine"]}: {len(r["results"])} results, ${r["cost"]}')

JavaScript 示例

JavaScript

const SCAVIO_KEY = process.env.SCAVIO_API_KEY;
const BRAVE_KEY = process.env.BRAVE_API_KEY;

async function search(query, count = 10) {
  try {
    const resp = await fetch('https://api.scavio.dev/api/v1/search', {
      method: 'POST',
      headers: { 'x-api-key': SCAVIO_KEY, 'Content-Type': 'application/json' },
      body: JSON.stringify({ query, country_code: 'us', num_results: count })
    });
    const results = (await resp.json()).organic_results || [];
    if (results.length >= 3) return { results, engine: 'scavio', cost: 0.005 };
  } catch {}
  if (BRAVE_KEY) {
    try {
      const resp = await fetch(`https://api.search.brave.com/res/v1/web/search?q=${encodeURIComponent(query)}&count=${count}`, {
        headers: { 'X-Subscription-Token': BRAVE_KEY }
      });
      const results = (await resp.json()).web?.results || [];
      return { results, engine: 'brave', cost: 0.01 };
    } catch {}
  }
  return { results: [], engine: 'none', cost: 0 };
}

search('python framework 2026').then(r => console.log(`${r.engine}: ${r.results.length} results`));

预期输出

JSON

Configured 2 search engines in cascade
  scavio: $0.005/query, min 3 results
  brave: $0.005/query, min 3 results

Engine: scavio
Results: 10
Cost: $0.005
  scavio: 10 results, 245ms

[news] latest AI news today -> scavio (10 results, $0.005)
[advanced] site:github.com python search api -> scavio (8 results, $0.005)
[tutorial] how to build a search agent -> scavio (10 results, $0.005)

如何构建多引擎搜索后备代理

前置条件

操作指南

步骤 1: 定义搜索引擎级联

步骤 2: 构建级联搜索功能

步骤 3: 添加根据查询类型智能选择引擎

Python 示例

JavaScript 示例

预期输出

相关教程

常见问题

完成如何构建多引擎搜索后备代理教程需要多长时间？

开始前需要准备什么？

我可以用免费套餐运行本教程吗？

这支持哪些框架？

相关资源

Google I/O 2026 AI模式变化后最佳搜索API

搜索 API 供应商格局（2026）

2026 年最佳 SERP API 提供商按价格排名

免费搜索API层级对比

Search APIs (Scavio, Tavily, SerpAPI) vs Headless Browser (Playwright, Puppeteer, Browserbase)

Google Places API vs SERP Local Pack API

开始构建

如何构建多引擎搜索后备代理

前置条件

操作指南

步骤 1: 定义搜索引擎级联

步骤 2: 构建级联搜索功能

步骤 3: 添加根据查询类型智能选择引擎

Python 示例

JavaScript 示例

预期输出

相关教程

常见问题

完成如何构建多引擎搜索后备代理教程需要多长时间？

开始前需要准备什么？

我可以用免费套餐运行本教程吗？

这支持哪些框架？

相关资源

Google I/O 2026 AI模式变化后最佳搜索API

搜索 API 供应商格局（2026）

2026 年最佳 SERP API 提供商按价格排名

免费搜索API层级对比

Search APIs (Scavio, Tavily, SerpAPI) vs Headless Browser (Playwright, Puppeteer, Browserbase)

Google Places API vs SERP Local Pack API

开始构建