Re: [Qemu-devel] [PATCH v2 01/15] tests: Add utilities for docker testing

[Fam Zheng]

On Mon, 02/29 16:46, Alex Bennée wrote:
> 
> Fam Zheng <address@hidden> writes:
> 
> > 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    | 113 
> > ++++++++++++++++++++++++++++++++++++++++++++++
> >  tests/docker/docker_build |  42 +++++++++++++++++
> >  tests/docker/docker_clean |  22 +++++++++
> >  tests/docker/docker_run   |  29 ++++++++++++
> >  4 files changed, 206 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..d175a86
> > --- /dev/null
> > +++ b/tests/docker/docker.py
> > @@ -0,0 +1,113 @@
> > +#!/usr/bin/env python2 -B
> > +#
> > +# 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 subprocess
> > +import json
> > +import hashlib
> > +import atexit
> > +import uuid
> > +
> > +class ContainerTerminated(Exception):
> > +    """ Raised if the container has already existed """
> > +    pass
> > +
> > +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"]
> 
> Hmm ps -q barfs on my command line:
> 
> 16:04 address@hidden/x86_64  [qemu.git/mttcg/multi_tcg_v8_ajb-r2] >ps -q
> error: unsupported SysV option
> 
> Is there not a more portable way of doing this, even if it is a standard
> library?

Down the road this is "sudo docker ps" command. :)

> 
> > +        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):
> > +        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, 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
> 
> I think it might be useful to catch some arguments here for testing
> things. It is likely to be the first script someone runs while poking
> around so some help text would be useful even if it just points at the
> other commands.

Sure, I can do that.

> 
> In fact I'm not sure why all the various commands aren't in one script
> for now given this does most of the heavy lifting.

OK, I can merge them into one script.


> 
> > +
> > diff --git a/tests/docker/docker_build b/tests/docker/docker_build
> > new file mode 100755
> > index 0000000..6948e2c
> > --- /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 <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 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
> > +
> > +    dkr = docker.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)
> > +    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 <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 sys
> > +import docker
> > +
> > +def main():
> > +    docker.Docker().clean()
> > +    return 0
> > +
> > +if __name__ == "__main__":
> > +    sys.exit(main())
> 
> Of all the scripts run if you call with --help this just does something
> straight away. It should at least attempt a usage() text to prevent
> accidents.

Yes. Will address.

Fam

> 
> > diff --git a/tests/docker/docker_run b/tests/docker/docker_run
> > new file mode 100755
> > index 0000000..4c46d90
> > --- /dev/null
> > +++ b/tests/docker/docker_run
> > @@ -0,0 +1,29 @@
> > +#!/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 <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 sys
> > +import argparse
> > +import docker
> > +
> > +def main():
> > +    parser = argparse.ArgumentParser()
> > +    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")
> > +    args, argv = parser.parse_known_args()
> > +    return docker.Docker().run(argv, args.keep, quiet=args.quiet)
> > +
> > +if __name__ == "__main__":
> > +    sys.exit(main())
> 
> 
> --
> Alex Bennée