[Qemu-devel] [PATCH v3 01/13] tests: Add utilities for docker testing

[Fam Zheng]

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 <address@hidden>
---
 tests/docker/docker.py | 180 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 180 insertions(+)
 create mode 100755 tests/docker/docker.py

diff --git a/tests/docker/docker.py b/tests/docker/docker.py
new file mode 100755
index 0000000..22f537c
--- /dev/null
+++ b/tests/docker/docker.py
@@ -0,0 +1,180 @@
+#!/usr/bin/env python2
+#
+# Docker controlling module
+#
+# Copyright (c) 2016 Red Hat Inc.
+#
+# Authors:
+#  Fam Zheng <address@hidden>
+#
+# 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 subprocess
+import json
+import hashlib
+import atexit
+import uuid
+import argparse
+
+class Docker(object):
+    """ Running Docker commands """
+    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():
+            resp = self._output(["inspect", i])
+            labels = json.loads(resp)[0]["Config"]["Labels"]
+            active = json.loads(resp)[0]["State"]["Running"]
+            if not labels:
+                continue
+            instance_uuid = labels.get("com.qemu.instance.uuid", None)
+            if not instance_uuid:
+                continue
+            if only_known and instance_uuid 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):
+        commands = [["docker"], ["sudo", "-n", "docker"]]
+        for cmd in commands:
+            if subprocess.call(cmd + ["images"],
+                               stdout=subprocess.PIPE,
+                               stderr=subprocess.PIPE) == 0:
+                return cmd
+        commands_txt = "\n".join(["  " + " ".join(x) for x in commands])
+        raise Exception("Cannot find working docker command. Tried:\n%s" % 
commands_txt)
+
+    def get_image_dockerfile_checksum(self, tag):
+        resp = self._output(["inspect", tag])
+        labels = json.loads(resp)[0]["Config"].get("Labels", {})
+        return labels.get("com.qemu.dockerfile-checksum", "")
+
+    def checksum(self, text):
+        return hashlib.sha1(text).hexdigest()
+
+    def build_image(self, tag, dockerfile, df, quiet=True, argv=[]):
+        tmp = dockerfile + "\n" + \
+              "LABEL com.qemu.dockerfile-checksum=%s" % 
self.checksum(dockerfile)
+        tmp_df = df + ".tmp"
+        tmp_file = open(tmp_df, "wb")
+        tmp_file.write(tmp)
+        tmp_file.close()
+        self._do(["build", "-t", tag, "-f", tmp_df] + argv + 
[os.path.dirname(df)],
+                 quiet=quiet)
+        os.unlink(tmp_df)
+
+    def image_matches_dockerfile(self, tag, dockerfile):
+        try:
+            checksum = self.get_image_dockerfile_checksum(tag)
+        except:
+            return False
+        return checksum == self.checksum(dockerfile)
+
+    def run(self, cmd, keep, quiet):
+        label = uuid.uuid1().hex
+        if not keep:
+            self._instances.append(label)
+        ret = self._do(["run", "--label", "com.qemu.instance.uuid=" + label] + 
cmd, quiet=quiet)
+        if not keep:
+            self._instances.remove(label)
+        return ret
+
+class SubCommand(object):
+    """A SubCommand template base class"""
+    name = None # Subcommand name
+    def args(self, parser):
+        """Setup argument parser"""
+        pass
+    def run(self, args, argv):
+        """Run command.
+        args: parsed argument by argument parser.
+        argv: remaining arguments from sys.argv.
+        """
+        pass
+
+class RunCommand(SubCommand):
+    """Invoke docker run and take care of cleaning up"""
+    name = "run"
+    def args(self, parser):
+        parser.add_argument("--keep", action="store_true",
+                            help="Don't remove image when the command 
completes")
+        parser.add_argument("--quiet", action="store_true",
+                            help="Run quietly unless an error occured")
+    def run(self, args, argv):
+        return Docker().run(argv, args.keep, quiet=args.quiet)
+
+class BuildCommand(SubCommand):
+    """ Build docker image out of a dockerfile"""
+    name = "build"
+    def args(self, parser):
+        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")
+
+    def run(self, args, argv):
+        dockerfile = open(args.dockerfile, "rb").read()
+        tag = args.tag
+
+        dkr = Docker()
+        if dkr.image_matches_dockerfile(tag, dockerfile):
+            if args.verbose:
+                print "Image is up to date."
+            return 0
+
+        quiet = not args.verbose
+        dkr.build_image(tag, dockerfile, args.dockerfile, quiet=quiet, 
argv=argv)
+        return 0
+
+class CleanCommand(SubCommand):
+    """Clean up docker instances"""
+    name = "clean"
+    def run(self, args, argv):
+        Docker().clean()
+        return 0
+
+def main():
+    parser = argparse.ArgumentParser()
+    subparsers = parser.add_subparsers()
+    for cls in SubCommand.__subclasses__():
+        cmd = cls()
+        subp = subparsers.add_parser(cmd.name, help=cmd.__doc__)
+        cmd.args(subp)
+        subp.set_defaults(cmdobj=cmd)
+    args, argv = parser.parse_known_args()
+    return args.cmdobj.run(args, argv)
+
+if __name__ == "__main__":
+    sys.exit(main())
-- 
2.4.3