feat: add Tavily as parallel search provider in backend

backend/app/services/search_service.py

@@ -10,6 +10,7 @@
 from app.models.search_model import SearchResult
 from app.utils.rate_limter import rate_limit
 from app.services.youtube_service import YouTubeAPIError
+from tavily import TavilyClient
 
 # Constants
 BING_ENDPOINT = "https://api.bing.microsoft.com/v7.0/search"
@@ -240,25 +241,65 @@ def search_youtube(query: str) -> List[SearchResult]:
     except Exception as e:
         raise YouTubeAPIError(f"YouTube search failed: {str(e)}")
 
+@rate_limit(calls=CALLS_PER_MINUTE, period=60)
+def search_tavily(query: str) -> List[SearchResult]:
+    """Perform a Tavily search for the given query.
+
+    Args:
+        query: The search query to perform
+
+    Returns:
+        List of SearchResult objects
+
+    Raises:
+        SearchAPIError: If the Tavily API request fails
+    """
+    api_key = os.getenv('TAVILY_API_KEY')
+    if not api_key:
+        raise SearchAPIError("TAVILY_API_KEY environment variable not set")
+
+    try:
+        client = TavilyClient(api_key=api_key)
+        response = client.search(query, max_results=RESULTS_PER_ENGINE)
+
+        results = []
+        for item in response.get("results", []):
+            search_result = SearchResult(
+                question=query,
+                title=item.get("title", ""),
+                url=item.get("url", ""),
+                snippet=item.get("content", ""),
+                search_content=item.get("raw_content") or item.get("content", ""),
+                source="tavily"
+            )
+            results.append(search_result)
+
+        return results
+
+    except Exception as e:
+        logger.error(f"Tavily search error: {str(e)}")
+        raise SearchAPIError(f"Tavily search failed: {str(e)}")
+
 def perform_search(query: str) -> List[SearchResult]:
-    """Perform parallel searches on Google, Bing, and YouTube APIs.
-    
+    """Perform parallel searches on Google, Bing, YouTube, and Tavily APIs.
+
     Args:
         query: The search query to run
-    
+
     Returns:
         Combined list of unique SearchResult objects
     """
     try:
-        with ThreadPoolExecutor(max_workers=3) as executor:
+        with ThreadPoolExecutor(max_workers=4) as executor:
             bing_future = executor.submit(search_bing, query)
             google_future = executor.submit(search_google, query)
             youtube_future = executor.submit(search_youtube, query)
-
+            tavily_future = executor.submit(search_tavily, query)
+
             results = []
-            
+
             # Gather results, handling potential failures
-            for future in [bing_future, google_future, youtube_future]:
+            for future in [bing_future, google_future, youtube_future, tavily_future]:
                 try:
                     results.extend(future.result())
                 except (SearchAPIError, YouTubeAPIError) as e:

backend/requirements.txt

@@ -6,4 +6,5 @@ python-decouple
 pydantic-settings
 # Add any other dependencies your project needs
 gunicorn
-bs4
+bs4
+tavily-python

backend/tests/test_search_service.py

@@ -1,7 +1,9 @@
 import pytest
-from app.services.search_service import perform_search, fetch_content_from_custom_url
+from unittest.mock import patch, MagicMock
+from app.services.search_service import perform_search, fetch_content_from_custom_url, search_tavily, SearchAPIError
 from app.models.search_model import SearchResult
 
+
 @pytest.mark.asyncio
 async def test_custom_url_fetch():
     print("Running test_custom_url_fetch")
@@ -14,3 +16,78 @@ async def test_custom_url_fetch():
     url = "https://example.com"
     with pytest.raises(Exception):
         await fetch_content_from_custom_url(url)
+
+
+def test_search_tavily_missing_key():
+    """Test that search_tavily raises SearchAPIError when TAVILY_API_KEY is not set."""
+    with patch.dict("os.environ", {}, clear=True):
+        with pytest.raises(SearchAPIError, match="TAVILY_API_KEY"):
+            search_tavily("test query")
+
+
+def test_search_tavily_success():
+    """Test that search_tavily returns correctly mapped SearchResult objects."""
+    mock_response = {
+        "results": [
+            {
+                "title": "Tavily Result 1",
+                "url": "https://example.com/1",
+                "content": "Snippet for result 1",
+                "raw_content": "Full content for result 1",
+            },
+            {
+                "title": "Tavily Result 2",
+                "url": "https://example.com/2",
+                "content": "Snippet for result 2",
+                "raw_content": None,
+            },
+        ]
+    }
+    mock_client = MagicMock()
+    mock_client.search.return_value = mock_response
+
+    with patch.dict("os.environ", {"TAVILY_API_KEY": "tvly-test-key"}):
+        with patch("app.services.search_service.TavilyClient", return_value=mock_client):
+            results = search_tavily("test query")
+
+    assert len(results) == 2
+    assert results[0].source == "tavily"
+    assert results[0].title == "Tavily Result 1"
+    assert results[0].url == "https://example.com/1"
+    assert results[0].snippet == "Snippet for result 1"
+    assert results[0].search_content == "Full content for result 1"
+    # When raw_content is None, falls back to content
+    assert results[1].search_content == "Snippet for result 2"
+
+
+def test_search_tavily_api_error():
+    """Test that search_tavily wraps API errors as SearchAPIError."""
+    mock_client = MagicMock()
+    mock_client.search.side_effect = Exception("API rate limit exceeded")
+
+    with patch.dict("os.environ", {"TAVILY_API_KEY": "tvly-test-key"}):
+        with patch("app.services.search_service.TavilyClient", return_value=mock_client):
+            with pytest.raises(SearchAPIError, match="Tavily search failed"):
+                search_tavily("test query")
+
+
+def test_perform_search_includes_tavily():
+    """Test that perform_search includes Tavily results in combined output."""
+    tavily_result = SearchResult(
+        question="test",
+        title="Tavily Result",
+        url="https://tavily.example.com",
+        snippet="tavily snippet",
+        search_content="tavily content",
+        source="tavily",
+    )
+
+    with patch("app.services.search_service.search_bing", side_effect=SearchAPIError("no key")), \
+         patch("app.services.search_service.search_google", side_effect=SearchAPIError("no key")), \
+         patch("app.services.search_service.search_youtube", side_effect=SearchAPIError("no key")), \
+         patch("app.services.search_service.search_tavily", return_value=[tavily_result]):
+        results = perform_search("test")
+
+    assert len(results) == 1
+    assert results[0].source == "tavily"
+    assert results[0].url == "https://tavily.example.com"

readme.md

@@ -228,6 +228,7 @@ Open [http://localhost:5173](http://localhost:5173) and start asking.
 | `GOOGLE_API_KEY`          |    ✅    | Google Custom Search API key                        |
 | `GOOGLE_SEARCH_CX`        |    ✅    | Custom Search Engine ID                             |
 | `BING_API_KEY`            |    ✅    | Bing Web Search v7 key                              |
+| `TAVILY_API_KEY`          |          | Tavily Search API key (optional, additive provider)  |
 | `CLERK_SECRET_KEY`        |          | Server-side Clerk verification                      |
 | `ALLOWED_ORIGINS`         |          | Comma-separated CORS origins                        |