fix: pass unstructured kwargs down in all unstructured loaders (#2506)

### Summary

#1667 updated several Unstructured loaders to accept
`unstructured_kwargs` in the `__init__` function. However, the previous
PR did not add this functionality to every Unstructured loader. This PR
ensures `unstructured_kwargs` are passed in all remaining Unstructured
loaders.

langchain/document_loaders/email.py

@@ -21,11 +21,11 @@ class UnstructuredEmailLoader(UnstructuredFileLoader):
         if filetype == FileType.EML:
             from unstructured.partition.email import partition_email
 
-            return partition_email(filename=self.file_path)
+            return partition_email(filename=self.file_path, **self.unstructured_kwargs)
         elif satisfies_min_unstructured_version("0.5.8") and filetype == FileType.MSG:
             from unstructured.partition.msg import partition_msg
 
-            return partition_msg(filename=self.file_path)
+            return partition_msg(filename=self.file_path, **self.unstructured_kwargs)
         else:
             raise ValueError(
                 f"Filetype {filetype} is not supported in UnstructuredEmailLoader."

langchain/document_loaders/epub.py

@@ -19,4 +19,4 @@ class UnstructuredEPubLoader(UnstructuredFileLoader):
             )
         from unstructured.partition.epub import partition_epub
 
-        return partition_epub(filename=self.file_path)
+        return partition_epub(filename=self.file_path, **self.unstructured_kwargs)

langchain/document_loaders/markdown.py

@@ -22,4 +22,4 @@ class UnstructuredMarkdownLoader(UnstructuredFileLoader):
                 "Partitioning markdown files is only supported in unstructured>=0.4.16."
             )
 
-        return partition_md(filename=self.file_path)
+        return partition_md(filename=self.file_path, **self.unstructured_kwargs)

langchain/document_loaders/url.py

@@ -1,6 +1,6 @@
 """Loader that uses unstructured to load HTML files."""
 import logging
-from typing import List
+from typing import Any, List
 
 from langchain.docstore.document import Document
 from langchain.document_loaders.base import BaseLoader
@@ -12,7 +12,11 @@ class UnstructuredURLLoader(BaseLoader):
     """Loader that uses unstructured to load HTML files."""
 
     def __init__(
-        self, urls: List[str], continue_on_failure: bool = True, headers: dict = {}
+        self,
+        urls: List[str],
+        continue_on_failure: bool = True,
+        headers: dict = {},
+        **unstructured_kwargs: Any,
     ):
         """Initialize with file path."""
         try:
@@ -35,6 +39,7 @@ class UnstructuredURLLoader(BaseLoader):
         self.urls = urls
         self.continue_on_failure = continue_on_failure
         self.headers = headers
+        self.unstructured_kwargs = unstructured_kwargs
 
     def __is_headers_available(self) -> bool:
         _unstructured_version = self.__version.split("-")[0]
@@ -50,9 +55,11 @@ class UnstructuredURLLoader(BaseLoader):
         for url in self.urls:
             try:
                 if self.__is_headers_available():
-                    elements = partition_html(url=url, headers=self.headers)
+                    elements = partition_html(
+                        url=url, headers=self.headers, **self.unstructured_kwargs
+                    )
                 else:
-                    elements = partition_html(url=url)
+                    elements = partition_html(url=url, **self.unstructured_kwargs)
             except Exception as e:
                 if self.continue_on_failure:
                     logger.error(f"Error fetching or processing {url}, exeption: {e}")