[Qemu-devel] [RFC PATCH 2/3] dcoker: docker.py add check sub-command

["Alex Bennée" <alex.bennee@linaro.org>]

This command allows you to check if we need to re-build a docker
image. If the image isn't in the repository or the checksums don't
match then we return false and some text (for processing in
makefiles).

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
---
 tests/docker/docker.py | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/tests/docker/docker.py b/tests/docker/docker.py
index 80efa641c5..c2763957c9 100755
--- a/tests/docker/docker.py
+++ b/tests/docker/docker.py
@@ -441,6 +441,28 @@ class CcCommand(SubCommand):
         return Docker().command("run", cmd, args.quiet)
 
 
+class CheckCommand(SubCommand):
+    """Check if we need to re-build a docker image out of a dockerfile. Arguments: <tag> <dockerfile>"""
+    name = "check"
+    def args(self, parser):
+        parser.add_argument("tag",
+                            help="Image Tag")
+        parser.add_argument("dockerfile",
+                            help="Dockerfile name")
+
+    def run(self, args, argv):
+        dockerfile = open(args.dockerfile, "rb").read()
+        tag = args.tag
+
+        dkr = Docker()
+        if dkr.image_matches_dockerfile(tag, dockerfile):
+            if not args.quiet:
+                print "Image is up to date."
+            return 0
+        else:
+            print "Image needs updating"
+            return 1
+
 def main():
     parser = argparse.ArgumentParser(description="A Docker helper",
             usage="%s <subcommand> ..." % os.path.basename(sys.argv[0]))
-- 
2.17.1