From a6b9ca1c622a44d0e1124b9ea5ba70464e094d73 Mon Sep 17 00:00:00 2001
From: Markus Friedrich <friedrich.at.gc@googlemail.com>
Date: Sat, 27 Jul 2019 09:47:34 +0200
Subject: [PATCH] Reset uid and gid to 0 when creating the context tar file.

This is needed to avoid unexpected build cache invalidations due to
changed ownership.
docker-cli does it also this way.

Signed-off-by: Markus Friedrich <friedrich.at.gc@googlemail.com>
---
 docker/utils/build.py | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/docker/utils/build.py b/docker/utils/build.py
index 4fa57518..8233436b 100644
--- a/docker/utils/build.py
+++ b/docker/utils/build.py
@@ -91,6 +91,11 @@ def create_archive(root, files=None, fileobj=None, gzip=False,
             # and directories executable by default.
             i.mode = i.mode & 0o755 | 0o111
 
+        # reset uid and gid to 0 to avoid build cache invalidations due to
+        # changed ownership. (docker-cli does the same)
+        i.uid = 0
+        i.gid = 0
+
         if i.isfile():
             try:
                 with open(full_path, 'rb') as f: