feat: upgrade langchain (#430)

Co-authored-by: jyong <718720800@qq.com>

api/core/data_loader/loader/html.py

@@ -0,0 +1,35 @@
+import logging
+from typing import List
+
+from bs4 import BeautifulSoup
+from langchain.document_loaders.base import BaseLoader
+from langchain.schema import Document
+
+logger = logging.getLogger(__name__)
+
+
+class HTMLLoader(BaseLoader):
+    """Load html files.
+
+
+    Args:
+        file_path: Path to the file to load.
+    """
+
+    def __init__(
+        self,
+        file_path: str
+    ):
+        """Initialize with file path."""
+        self._file_path = file_path
+
+    def load(self) -> List[Document]:
+        return [Document(page_content=self._load_as_text())]
+
+    def _load_as_text(self) -> str:
+        with open(self._file_path, "rb") as fp:
+            soup = BeautifulSoup(fp, 'html.parser')
+            text = soup.get_text()
+            text = text.strip() if text else ''
+
+        return text