Harrison/youtube multi language (#5758)

Co-authored-by: rafly lesmana <raflylesmana111@gmail.com>

docs/modules/indexes/document_loaders/examples/youtube_transcript.ipynb

@@ -1,6 +1,7 @@
 {
  "cells": [
   {
+   "attachments": {},
    "cell_type": "markdown",
    "id": "df770c72",
    "metadata": {},
@@ -55,11 +56,12 @@
    ]
   },
   {
+   "attachments": {},
    "cell_type": "markdown",
    "id": "6b278a1b",
    "metadata": {},
    "source": [
-    "## Add video info"
+    "### Add video info"
    ]
   },
   {
@@ -79,20 +81,36 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "loader = YoutubeLoader.from_youtube_url(\"https://www.youtube.com/watch?v=QsYGlZkevEg\", add_video_info=True)"
+    "loader = YoutubeLoader.from_youtube_url(\"https://www.youtube.com/watch?v=QsYGlZkevEg\", add_video_info=True)\n",
+    "loader.load()"
+   ]
+  },
+  {
+   "attachments": {},
+   "cell_type": "markdown",
+   "id": "fc417e31",
+   "metadata": {},
+   "source": [
+    "### Add language preferences\n",
+    "\n",
+    "Language param : It's a list of language codes in a descending priority, `en` by default.\n",
+    "\n",
+    "translation param : It's a translate preference when the youtube does'nt have your select language, `en` by default."
    ]
   },
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "97b98e92",
+   "id": "08510625",
    "metadata": {},
    "outputs": [],
    "source": [
+    "loader = YoutubeLoader.from_youtube_url(\"https://www.youtube.com/watch?v=QsYGlZkevEg\", add_video_info=True, language=['en','id'], translation='en')\n",
     "loader.load()"
    ]
   },
   {
+   "attachments": {},
    "cell_type": "markdown",
    "id": "65796cc5",
    "metadata": {},

langchain/document_loaders/youtube.py

@@ -3,7 +3,7 @@ from __future__ import annotations
 
 import logging
 from pathlib import Path
-from typing import Any, Dict, List, Optional
+from typing import Any, Dict, List, Optional, Sequence, Union
 from urllib.parse import parse_qs, urlparse
 
 from pydantic import root_validator
@@ -146,13 +146,19 @@ class YoutubeLoader(BaseLoader):
         self,
         video_id: str,
         add_video_info: bool = False,
-        language: str = "en",
+        language: Union[str, Sequence[str]] = "en",
+        translation: str = "en",
         continue_on_failure: bool = False,
     ):
         """Initialize with YouTube video ID."""
         self.video_id = video_id
         self.add_video_info = add_video_info
         self.language = language
+        if isinstance(language, str):
+            self.language = [language]
+        else:
+            self.language = language
+        self.translation = translation
         self.continue_on_failure = continue_on_failure
 
     @staticmethod
@@ -199,10 +205,10 @@ class YoutubeLoader(BaseLoader):
             return []
 
         try:
-            transcript = transcript_list.find_transcript([self.language])
+            transcript = transcript_list.find_transcript(self.language)
         except NoTranscriptFound:
             en_transcript = transcript_list.find_transcript(["en"])
-            transcript = en_transcript.translate(self.language)
+            transcript = en_transcript.translate(self.translation)
 
         transcript_pieces = transcript.fetch()