Add file filter param to Git loader (#2904)

Allows users to specify what files should be loaded instead of
indiscriminately loading the entire repo.

extends #2851 

NOTE: for reviewers, `hide whitespace` option recommended since I
changed the indentation of an if-block to use `continue` instead so it
looks less like a Christmas tree :)

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

@@ -18,7 +18,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 21,
+   "execution_count": 5,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -32,7 +32,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 22,
+   "execution_count": null,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -41,7 +41,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 23,
+   "execution_count": 6,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -50,7 +50,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 24,
+   "execution_count": 8,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -59,27 +59,16 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 25,
+   "execution_count": null,
    "metadata": {},
-   "outputs": [
-    {
-     "data": {
-      "text/plain": [
-       "1040"
-      ]
-     },
-     "execution_count": 25,
-     "metadata": {},
-     "output_type": "execute_result"
-    }
-   ],
+   "outputs": [],
    "source": [
     "len(data)"
    ]
   },
   {
    "cell_type": "code",
-   "execution_count": 26,
+   "execution_count": 9,
    "metadata": {},
    "outputs": [
     {
@@ -103,7 +92,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 27,
+   "execution_count": 5,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -112,7 +101,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 28,
+   "execution_count": 2,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -125,7 +114,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 29,
+   "execution_count": 10,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -134,16 +123,16 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 30,
+   "execution_count": 11,
    "metadata": {},
    "outputs": [
     {
      "data": {
       "text/plain": [
-       "1040"
+       "1074"
       ]
      },
-     "execution_count": 30,
+     "execution_count": 11,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -152,6 +141,25 @@
     "len(data)"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Filtering files to load"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 12,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "from langchain.document_loaders import GitLoader\n",
+    "\n",
+    "# eg. loading only python files\n",
+    "loader = GitLoader(repo_path=\"./example_data/test_repo1/\", file_filter=lambda file_path: file_path.endswith(\".py\"))"
+   ]
+  },
   {
    "cell_type": "code",
    "execution_count": null,
@@ -176,7 +184,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.9.1"
+   "version": "3.11.3"
   }
  },
  "nbformat": 4,

langchain/document_loaders/git.py

@@ -1,5 +1,5 @@
 import os
-from typing import List, Optional
+from typing import Callable, List, Optional
 
 from langchain.docstore.document import Document
 from langchain.document_loaders.base import BaseLoader
@@ -21,10 +21,12 @@ class GitLoader(BaseLoader):
         repo_path: str,
         clone_url: Optional[str] = None,
         branch: Optional[str] = "main",
+        file_filter: Optional[Callable[[str], bool]] = None,
     ):
         self.repo_path = repo_path
         self.clone_url = clone_url
         self.branch = branch
+        self.file_filter = file_filter
 
     def load(self) -> List[Document]:
         try:
@@ -47,8 +49,15 @@ class GitLoader(BaseLoader):
         docs: List[Document] = []
 
         for item in repo.tree().traverse():
-            if isinstance(item, Blob):
+            if not isinstance(item, Blob):
+                continue
+
             file_path = os.path.join(self.repo_path, item.path)
+
+            # uses filter to skip files
+            if self.file_filter and not self.file_filter(file_path):
+                continue
+
             rel_file_path = os.path.relpath(file_path, self.repo_path)
             try:
                 with open(file_path, "rb") as f: