[Qemu-devel] [PATCH 01/12] tests: Add utilities for docker testing

[Fam Zheng <famz@redhat.com>]

docker_run: A wrapper for "docker run" (or "sudo -n docker run" if
necessary), which takes care of killing and removing the running
container at SIGINT.

docker_clean: A tool to tear down all the containers including inactive
ones that are started by docker_run.

docker_build: A tool to compare an image from given dockerfile and
rebuild it if they're different.

Signed-off-by: Fam Zheng <famz@redhat.com>
---
 tests/docker/docker.py    | 108 ++++++++++++++++++++++++++++++++++++++++++++++
 tests/docker/docker_build |  42 ++++++++++++++++++
 tests/docker/docker_clean |  22 ++++++++++
 tests/docker/docker_run   |  28 ++++++++++++
 4 files changed, 200 insertions(+)
 create mode 100755 tests/docker/docker.py
 create mode 100755 tests/docker/docker_build
 create mode 100755 tests/docker/docker_clean
 create mode 100755 tests/docker/docker_run

diff --git a/tests/docker/docker.py b/tests/docker/docker.py
new file mode 100755
index 0000000..e513da0
--- /dev/null
+++ b/tests/docker/docker.py
@@ -0,0 +1,108 @@
+#!/usr/bin/env python2 -B
+#
+# Docker controlling module
+#
+# Copyright (c) 2016 Red Hat Inc.
+#
+# Authors:
+#  Fam Zheng <famz@redhat.com>
+#
+# This work is licensed under the terms of the GNU GPL, version 2
+# or (at your option) any later version. See the COPYING file in
+# the top-level directory.
+
+import os
+import subprocess
+import json
+import hashlib
+import atexit
+import time
+import uuid
+
+class ContainerTerminated(Exception):
+    pass
+
+class Docker(object):
+    def __init__(self):
+        self._command = self._guess_command()
+        self._instances = []
+        atexit.register(self._kill_instances)
+
+    def _do(self, cmd, quiet=True, **kwargs):
+        if quiet:
+            kwargs["stdout"] = subprocess.PIPE
+        return subprocess.call(self._command + cmd, **kwargs)
+
+    def _do_kill_instances(self, only_known, only_active=True):
+        cmd = ["ps", "-q"]
+        if not only_active:
+            cmd.append("-a")
+        for i in self._output(cmd).split():
+            r = self._output(["inspect", i])
+            labels = json.loads(r)[0]["Config"]["Labels"]
+            active = json.loads(r)[0]["State"]["Running"]
+            if not labels:
+                continue
+            u = labels.get("com.qemu.instance.uuid", None)
+            if not u:
+                continue
+            if only_known and u not in self._instances:
+                continue
+            print "Terminating", i
+            if active:
+                self._do(["kill", i])
+            self._do(["rm", i])
+
+    def clean(self):
+        self._do_kill_instances(False, False)
+        return 0
+
+    def _kill_instances(self):
+        return self._do_kill_instances(True)
+
+    def _output(self, cmd, **kwargs):
+        return subprocess.check_output(self._command + cmd,
+                                       stderr=subprocess.STDOUT,
+                                       **kwargs)
+
+    def _guess_command(self):
+        for c in [["docker"], ["sudo", "-n", "docker"]]:
+            if subprocess.call(c + ["images"],
+                               stdout=subprocess.PIPE,
+                               stderr=subprocess.PIPE) == 0:
+                return c
+        raise Exception("Cannot find working docker command")
+
+    def get_image_dockerfile_checksum(self, tag):
+        resp = self._output(["inspect", tag])
+        t = json.loads(resp)[0]
+        return t["Config"].get("Labels", {}).get("com.qemu.dockerfile-checksum", "")
+
+    def checksum(self, text):
+        return hashlib.sha1(text).hexdigest()
+
+    def build_image(self, tag, dockerfile, df, quiet=True):
+        tmp = dockerfile + "\n" + \
+              "LABEL com.qemu.dockerfile-checksum=%s" % self.checksum(dockerfile)
+        tmp_df = df + ".tmp"
+        f = open(tmp_df, "wb")
+        f.write(tmp)
+        f.close()
+        self._do(["build", "-t", tag, "-f", tmp_df, os.path.dirname(df)],
+                 quiet=quiet)
+        os.unlink(tmp_df)
+
+    def image_matches_dockerfile(self, tag, dockerfile):
+        try:
+            a = self.get_image_dockerfile_checksum(tag)
+        except:
+            return False
+        return a == self.checksum(dockerfile)
+
+    def run(self, cmd, quiet, **kwargs):
+        label = uuid.uuid1().hex
+        self._instances.append(label)
+        r = self._do(["run", "--label", "com.qemu.instance.uuid=" + label] + cmd, quiet=quiet)
+        self._instances.remove(label)
+        return r
+
diff --git a/tests/docker/docker_build b/tests/docker/docker_build
new file mode 100755
index 0000000..b4f0dec
--- /dev/null
+++ b/tests/docker/docker_build
@@ -0,0 +1,42 @@
+#!/usr/bin/env python2
+#
+# Compare to Dockerfile and rebuild a docker image if necessary.
+#
+# Copyright (c) 2016 Red Hat Inc.
+#
+# Authors:
+#  Fam Zheng <famz@redhat.com>
+#
+# This work is licensed under the terms of the GNU GPL, version 2
+# or (at your option) any later version. See the COPYING file in
+# the top-level directory.
+
+import sys
+import docker
+import argparse
+
+def main():
+    parser = argparse.ArgumentParser()
+    parser.add_argument("tag",
+                        help="Image Tag")
+    parser.add_argument("dockerfile",
+                        help="Dockerfile name")
+    parser.add_argument("--verbose", "-v", action="store_true",
+                        help="Print verbose information")
+    args = parser.parse_args()
+
+    dockerfile = open(args.dockerfile, "rb").read()
+    tag = args.tag
+
+    d = docker.Docker()
+    if d.image_matches_dockerfile(tag, dockerfile):
+        if args.verbose:
+            print "Image is up to date."
+        return 0
+
+    quiet = not args.verbose
+    d.build_image(tag, dockerfile, args.dockerfile, quiet=quiet)
+    return 0
+
+if __name__ == "__main__":
+    sys.exit(main())
diff --git a/tests/docker/docker_clean b/tests/docker/docker_clean
new file mode 100755
index 0000000..88cdba6
--- /dev/null
+++ b/tests/docker/docker_clean
@@ -0,0 +1,22 @@
+#!/usr/bin/env python2
+#
+# Clean up uselsee containers.
+#
+# Copyright (c) 2016 Red Hat Inc.
+#
+# Authors:
+#  Fam Zheng <famz@redhat.com>
+#
+# This work is licensed under the terms of the GNU GPL, version 2
+# or (at your option) any later version. See the COPYING file in
+# the top-level directory.
+
+import sys
+import docker
+
+def main():
+    docker.Docker().clean()
+    return 0
+
+if __name__ == "__main__":
+    sys.exit(main())
diff --git a/tests/docker/docker_run b/tests/docker/docker_run
new file mode 100755
index 0000000..5cf9d04
--- /dev/null
+++ b/tests/docker/docker_run
@@ -0,0 +1,28 @@
+#!/usr/bin/env python2
+#
+# Wrapper for "docker run" with automatical clean up if the execution is
+# iterrupted.
+#
+# Copyright (c) 2016 Red Hat Inc.
+#
+# Authors:
+#  Fam Zheng <famz@redhat.com>
+#
+# This work is licensed under the terms of the GNU GPL, version 2
+# or (at your option) any later version. See the COPYING file in
+# the top-level directory.
+
+import os
+import sys
+import argparse
+import docker
+
+def main():
+    parser = argparse.ArgumentParser()
+    parser.add_argument("--quiet", action="store_true",
+                        help="Run quietly unless an error occured")
+    args, argv = parser.parse_known_args()
+    return docker.Docker().run(argv, quiet=args.quiet)
+
+if __name__ == "__main__":
+    sys.exit(main())
-- 
2.4.3