community: Add you.com utility, update you retriever integration docs (#17014)

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- **Description: changes to you.com files** 
    - general cleanup
- adds community/utilities/you.py, moving bulk of code from retriever ->
utility
    - removes `snippet` as endpoint
    - adds `news` as endpoint
    - adds more tests

<s>**Description: update community MAKE file** 
    - adds `integration_tests`
    - adds `coverage`</s>

- **Issue:** the issue # it fixes if applicable,
- [For New Contributors: Update Integration
Documentation](https://github.com/langchain-ai/langchain/issues/15664#issuecomment-1920099868)
- **Dependencies:** n/a
- **Twitter handle:** @scottnath
- **Mastodon handle:** scottnath@mastodon.social

---------

Co-authored-by: Bagatur <baskaryan@gmail.com>

libs/community/langchain_community/retrievers/you.py

@@ -1,64 +1,23 @@
-from typing import Any, Dict, List, Optional
+from typing import Any, List
 
 from langchain_core.callbacks import CallbackManagerForRetrieverRun
 from langchain_core.documents import Document
-from langchain_core.pydantic_v1 import root_validator
 from langchain_core.retrievers import BaseRetriever
-from langchain_core.utils import get_from_dict_or_env
+
+from langchain_community.utilities import YouSearchAPIWrapper
 
 
-class YouRetriever(BaseRetriever):
+class YouRetriever(BaseRetriever, YouSearchAPIWrapper):
     """`You` retriever that uses You.com's search API.
-
-    To connect to the You.com api requires an API key which
-    you can get by emailing api@you.com.
-    You can check out our docs at https://documentation.you.com.
-
-    You need to set the environment variable `YDC_API_KEY` for retriever to operate.
+    It wraps results() to get_relevant_documents
+    It uses all YouSearchAPIWrapper arguments without any change.
     """
 
-    ydc_api_key: str
-    k: Optional[int] = None
-    n_hits: Optional[int] = None
-    n_snippets_per_hit: Optional[int] = None
-    endpoint_type: str = "web"
-
-    @root_validator(pre=True)
-    def validate_client(
-        cls,
-        values: Dict[str, Any],
-    ) -> Dict[str, Any]:
-        values["ydc_api_key"] = get_from_dict_or_env(
-            values, "ydc_api_key", "YDC_API_KEY"
-        )
-        return values
-
     def _get_relevant_documents(
-        self, query: str, *, run_manager: CallbackManagerForRetrieverRun
+        self,
+        query: str,
+        *,
+        run_manager: CallbackManagerForRetrieverRun,
+        **kwargs: Any,
     ) -> List[Document]:
-        import requests
-
-        headers = {"X-API-Key": self.ydc_api_key}
-        if self.endpoint_type == "web":
-            results = requests.get(
-                f"https://api.ydc-index.io/search?query={query}",
-                headers=headers,
-            ).json()
-
-            docs = []
-            n_hits = self.n_hits or len(results["hits"])
-            for hit in results["hits"][:n_hits]:
-                n_snippets_per_hit = self.n_snippets_per_hit or len(hit["snippets"])
-                for snippet in hit["snippets"][:n_snippets_per_hit]:
-                    docs.append(Document(page_content=snippet))
-                    if self.k is not None and len(docs) >= self.k:
-                        return docs
-            return docs
-        elif self.endpoint_type == "snippet":
-            results = requests.get(
-                f"https://api.ydc-index.io/snippet_search?query={query}",
-                headers=headers,
-            ).json()
-            return [Document(page_content=snippet) for snippet in results]
-        else:
-            raise RuntimeError(f"Invalid endpoint type provided {self.endpoint_type}")
+        return self.results(query, run_manager=run_manager.get_child(), **kwargs)