kolla-build: Add Docker BuildKit support via docker buildx build

Add --buildkit flag to use docker buildx build instead of the docker-py
SDK. An optional --buildkit-builder selects a named buildx builder
instance, enabling docker-container or remote drivers for multi-arch
builds.

--buildkit and --squash are mutually exclusive and rejected at startup.
PushTask is skipped when buildkit is active; push is handled inline.

Set buildkit as the new default.

Change-Id: Idbf1d1bdc091bb84721f8006c2b916731b999859
Signed-off-by: Michal Nasiadka <mnasiadka@gmail.com>

2 files changed, 23 insertions, 0 deletions

diff --git a/kolla/common/config.py b/kolla/common/config.py
index c4ebcbf3b..b418552f4 100644
--- a/kolla/common/config.py
+++ b/kolla/common/config.py
@@ -171,6 +171,14 @@ _CLI_OPTS = [
                help='The Docker namespace name'),
     cfg.StrOpt('network_mode', default='host',
                help='The network mode for Docker build. Example: host'),
+    cfg.BoolOpt('buildkit', default=True,
+                help='Use Docker BuildKit (docker buildx build) when building '
+                     'images. Requires the docker-buildx-plugin to be '
+                     'installed. Only valid with --engine docker.'),
+    cfg.StrOpt('buildkit-builder', default=None,
+               help='Name of the docker buildx builder instance to use. '
+                    'If unset the currently active builder is used. '
+                    'Only valid with --buildkit.'),
     cfg.BoolOpt('cache', default=True,
                 help='Use the container engine cache when building'),
     cfg.StrOpt('patches-path', default=None,
diff --git a/kolla/common/utils.py b/kolla/common/utils.py
index 4ee80768f..485848ba2 100644
--- a/kolla/common/utils.py
+++ b/kolla/common/utils.py
@@ -54,6 +54,21 @@ def make_a_logger(conf=None, image_name=None):
 LOG = make_a_logger()
 
 
+def check_docker_buildx():
+    try:
+        subprocess.check_output(  # nosec
+            ['docker', 'buildx', 'version'], stderr=subprocess.STDOUT)
+    except OSError as ex:
+        if ex.errno == 2:
+            LOG.error('"docker" command is not found.')
+        raise
+    except subprocess.CalledProcessError:
+        LOG.error('"docker buildx" is not available. '
+                  'Install the docker-buildx-plugin or disable BuildKit '
+                  'with "--nobuildkit".')
+        raise
+
+
 def get_docker_squash_version():
 
     try: