feat(document_loaders): add tencent cos directory and file loader (#6401)

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- add tencent cos directory and file support for document-loader

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#### Who can review?

@eyurtsev

docs/extras/modules/data_connection/document_loaders/integrations/tencent_cos_directory.ipynb

@@ -0,0 +1,116 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "id": "a634365e",
+   "metadata": {},
+   "source": [
+    "# Tencent COS Directory\n",
+    "\n",
+    "This covers how to load document objects from a `Tencent COS Directory`."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "85e97267",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "#! pip install cos-python-sdk-v5"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "id": "2f0cd6a5",
+   "metadata": {
+    "tags": []
+   },
+   "outputs": [],
+   "source": [
+    "from langchain.document_loaders import TencentCOSDirectoryLoader\n",
+    "from qcloud_cos import CosConfig"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "id": "321cc7f1",
+   "metadata": {
+    "tags": []
+   },
+   "outputs": [],
+   "source": [
+    "conf = CosConfig(\n",
+    "        Region=\"your cos region\",\n",
+    "        SecretId=\"your cos secret_id\",\n",
+    "        SecretKey=\"your cos secret_key\",\n",
+    "    )\n",
+    "loader = TencentCOSDirectoryLoader(conf=conf, bucket=\"you_cos_bucket\")"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "4c50d2c7",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "loader.load()"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "0690c40a",
+   "metadata": {},
+   "source": [
+    "## Specifying a prefix\n",
+    "You can also specify a prefix for more finegrained control over what files to load."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 5,
+   "id": "72d44781",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "loader = TencentCOSDirectoryLoader(conf=conf, bucket=\"you_cos_bucket\", prefix=\"fake\")"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "2d3c32db",
+   "metadata": {
+    "scrolled": true
+   },
+   "outputs": [],
+   "source": [
+    "loader.load()"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3 (ipykernel)",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.9.6"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 5
+}

docs/extras/modules/data_connection/document_loaders/integrations/tencent_cos_file.ipynb

@@ -0,0 +1,91 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "id": "a634365e",
+   "metadata": {},
+   "source": [
+    "# Tencent COS File\n",
+    "\n",
+    "This covers how to load document object from a `Tencent COS File`."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "85e97267",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "#! pip install cos-python-sdk-v5"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "id": "2f0cd6a5",
+   "metadata": {
+    "tags": []
+   },
+   "outputs": [],
+   "source": [
+    "from langchain.document_loaders import TencentCOSFileLoader\n",
+    "from qcloud_cos import CosConfig"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "id": "321cc7f1",
+   "metadata": {
+    "tags": []
+   },
+   "outputs": [],
+   "source": [
+    "conf = CosConfig(\n",
+    "        Region=\"your cos region\",\n",
+    "        SecretId=\"your cos secret_id\",\n",
+    "        SecretKey=\"your cos secret_key\",\n",
+    "    )\n",
+    "loader = TencentCOSFileLoader(conf=conf, bucket=\"you_cos_bucket\", key=\"fake.docx\")"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "4c50d2c7",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "loader.load()"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "0690c40a",
+   "metadata": {},
+   "source": []
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3 (ipykernel)",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.9.6"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 5
+}