Re: [Qemu-devel] [PATCH v4 1/4] tests/docker: add basic user mapping support

[Fam Zheng <famz@redhat.com>]

On Thu, 02/16 12:34, Alex Bennée wrote:
> Currently all docker builds are done by exporting a tarball to the
> docker container and running the build as the containers root user.
> Other use cases are possible however and it is possible to map a part
> of users file-system to the container. This is useful for example for
> doing cross-builds of arbitrary source trees. For this to work
> smoothly the container needs to have a user created that maps cleanly
> to the host system.
> 
> This adds a -u option to the docker script so that:
> 
>   DEB_ARCH=armhf DEB_TYPE=stable ./tests/docker/docker.py build \
>     -u --include-executable=arm-linux-user/qemu-arm \
>     debian:armhf ./tests/docker/dockerfiles/debian-bootstrap.docker
> 
> Will build a container that can then be run like:
> 
>   docker run --rm -it -v /home/alex/lsrc/qemu/risu.git/:/src \
>     --user=alex:alex -w /src/ debian:armhf \
>     sh -c "make clean && ./configure -s && make"
> 
> All docker containers built will add the current user unless
> explicitly disabled by specifying NOUSER when invoking the Makefile:
> 
>   make docker-image-debian-armhf-cross NOUSER=1
> 
> Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
> Reviewed-by: Fam Zheng <famz@redhat.com>
> 
> ---
> v2
>   - write the useradd directly
>   - change long option to --add-current-user
> v3
>   - images -> image's
>   - add r-b
>   - add USER to Makefile
> v4
>   - s/USER/NOUSER/ and default to on
>   - fix the add-user code to skip if user already setup (for chained images)
> ---
>  tests/docker/Makefile.include |  2 ++
>  tests/docker/docker.py        | 16 ++++++++++++++--
>  2 files changed, 16 insertions(+), 2 deletions(-)
> 
> diff --git a/tests/docker/Makefile.include b/tests/docker/Makefile.include
> index 3f15d5aea8..4778b27ca8 100644
> --- a/tests/docker/Makefile.include
> +++ b/tests/docker/Makefile.include
> @@ -50,6 +50,7 @@ docker-image-%: $(DOCKER_FILES_DIR)/%.docker
>  	$(call quiet-command,\
>  		$(SRC_PATH)/tests/docker/docker.py build qemu:$* $< \
>  		$(if $V,,--quiet) $(if $(NOCACHE),--no-cache) \
> +		$(if $(NOUSER),,--add-current-user) \
>  		$(if $(EXECUTABLE),--include-executable=$(EXECUTABLE)),\
>  		"BUILD","$*")
>  
> @@ -99,6 +100,7 @@ docker:
>  	@echo '                         (default is 1)'
>  	@echo '    DEBUG=1              Stop and drop to shell in the created container'
>  	@echo '                         before running the command.'
> +	@echo '    NOUSER=1		Disable adding current user to containers passwd.'

Please expand tabs in the middle into whitespaces.

>  	@echo '    NOCACHE=1            Ignore cache when build images.'
>  	@echo '    EXECUTABLE=<path>    Include executable in image.'
>  
> diff --git a/tests/docker/docker.py b/tests/docker/docker.py
> index 37d83199e7..d277a2268f 100755
> --- a/tests/docker/docker.py
> +++ b/tests/docker/docker.py
> @@ -25,6 +25,7 @@ import signal
>  from tarfile import TarFile, TarInfo
>  from StringIO import StringIO
>  from shutil import copy, rmtree
> +from pwd import getpwuid
>  
>  
>  DEVNULL = open(os.devnull, 'wb')
> @@ -149,13 +150,21 @@ class Docker(object):
>          labels = json.loads(resp)[0]["Config"].get("Labels", {})
>          return labels.get("com.qemu.dockerfile-checksum", "")
>  
> -    def build_image(self, tag, docker_dir, dockerfile, quiet=True, argv=None):
> +    def build_image(self, tag, docker_dir, dockerfile,
> +                    quiet=True, user=False, argv=None):
>          if argv == None:
>              argv = []
>  
>          tmp_df = tempfile.NamedTemporaryFile(dir=docker_dir, suffix=".docker")
>          tmp_df.write(dockerfile)
>  
> +        if user:
> +            uid = os.getuid()
> +            uname = getpwuid(uid).pw_name
> +            tmp_df.write("\n")
> +            tmp_df.write("RUN id %s || useradd -u %d -U %s" %
> +                         (uname, uid, uname))

Please "2>/dev/null" the id command.

> +
>          tmp_df.write("\n")
>          tmp_df.write("LABEL com.qemu.dockerfile-checksum=%s" %
>                       _text_checksum(dockerfile))
> @@ -225,6 +234,9 @@ class BuildCommand(SubCommand):
>                              help="""Specify a binary that will be copied to the
>                              container together with all its dependent
>                              libraries""")
> +        parser.add_argument("--add-current-user", "-u", dest="user",
> +                            action="store_true",
> +                            help="Add the current user to image's passwd")
>          parser.add_argument("tag",
>                              help="Image Tag")
>          parser.add_argument("dockerfile",
> @@ -261,7 +273,7 @@ class BuildCommand(SubCommand):
>                                         docker_dir)
>  
>              dkr.build_image(tag, docker_dir, dockerfile,
> -                            quiet=args.quiet, argv=argv)
> +                            quiet=args.quiet, user=args.user, argv=argv)
>  
>              rmtree(docker_dir)
>  
> -- 
> 2.11.0
> 

Fam