From d6e484497688b69560f0cbdb06bcbc18f02250b8 Mon Sep 17 00:00:00 2001
From: Emma Smith <emma@emmatyping.dev>
Date: Wed, 28 May 2025 14:18:34 -0700
Subject: [PATCH 1/2] gh-134262: Add retries to downloads in
 PCbuild\get_external.py (GH-134820) (cherry picked from commit
 e9d845b41dca9ad84b76ef777d05e647a4b4d8cd)

Co-authored-by: Emma Smith <emma@emmatyping.dev>
---
 PCbuild/get_external.py | 23 +++++++++++++++++++++--
 1 file changed, 21 insertions(+), 2 deletions(-)

diff --git a/PCbuild/get_external.py b/PCbuild/get_external.py
index 4ecc8925349c93..99aff63882f5ba 100755
--- a/PCbuild/get_external.py
+++ b/PCbuild/get_external.py
@@ -9,6 +9,25 @@
 from urllib.request import urlretrieve
 
 
+def retrieve_with_retries(download_location, output_path, reporthook,
+                          max_retries=7):
+    """Download a file with exponential backoff retry and save to disk."""
+    for attempt in range(max_retries):
+        try:
+            resp = urlretrieve(
+                download_location,
+                output_path,
+                reporthook=reporthook,
+            )
+        except ConnectionError as ex:
+            if attempt == max_retries:
+                msg = f"Download from {download_location} failed."
+                raise OSError(msg) from ex
+            time.sleep(2.25**attempt)
+        else:
+            return resp
+
+
 def fetch_zip(commit_hash, zip_dir, *, org='python', binary=False, verbose):
     repo = f'cpython-{"bin" if binary else "source"}-deps'
     url = f'https://github.com/{org}/{repo}/archive/{commit_hash}.zip'
@@ -16,10 +35,10 @@ def fetch_zip(commit_hash, zip_dir, *, org='python', binary=False, verbose):
     if verbose:
         reporthook = print
     zip_dir.mkdir(parents=True, exist_ok=True)
-    filename, headers = urlretrieve(
+    filename, _headers = retrieve_with_retries(
         url,
         zip_dir / f'{commit_hash}.zip',
-        reporthook=reporthook,
+        reporthook
     )
     return filename
 

From 84a943d85d81fff22e1c6b52d842ef7c4244e090 Mon Sep 17 00:00:00 2001
From: Zachary Ware <zachary.ware@gmail.com>
Date: Wed, 28 May 2025 18:21:42 -0500
Subject: [PATCH 2/2] Fix off-by-one

(cherry-picked from e64395e8eb8d3a9e35e3e534e87d427ff27ab0a5)
---
 PCbuild/get_external.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/PCbuild/get_external.py b/PCbuild/get_external.py
index 99aff63882f5ba..8c1155c74a642c 100755
--- a/PCbuild/get_external.py
+++ b/PCbuild/get_external.py
@@ -12,7 +12,7 @@
 def retrieve_with_retries(download_location, output_path, reporthook,
                           max_retries=7):
     """Download a file with exponential backoff retry and save to disk."""
-    for attempt in range(max_retries):
+    for attempt in range(max_retries + 1):
         try:
             resp = urlretrieve(
                 download_location,