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

[John Snow]

On 02/05/2016 04:24 AM, Fam Zheng wrote:
> 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    | 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 <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 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 the sudo version fails (Say, because a password prompt shows up) we
get the unhelpful error "Cannot find working docker command."

Does your sudo not prompt you in your dev environment?

> +            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 <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
> +
> +    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 <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())
> 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 <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 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())
> 

-- 
—js