bazel run docker_build fails on osx

[pcj]

Running a docker_build rule should install the docker image like docker load -i bazel-genfiles/.../image.tar.

Running this rule generates an executable bash script. The script template from https://github.com/bazelbuild/bazel/blob/master/tools/build_defs/docker/incremental_load.sh.tpl#L27-L28 assumes the presence of gnu sed. BSD sed (osx) does not support the -r --regexp-extended flag and the script fails.

sed: illegal option -- r
usage: sed script [-Ealn] [-i extension] [file ...]
       sed [-Ealn] [-i extension] [-e script] ... [-f script_file] ... [file ...]
ERROR: Non-zero return code '1' from command: Process exited with status 1.

Fix could involve use awk instead, i.e. docker version -f '{{.Server.Version}}' | awk -F\. '{ print $1 }' that IIRC is more general-purpose for this task.

[mickeyreiss]

Here's a workaround for OS X that will work for me until #1716 is released:

brew install gnu-sed
PATH=/usr/local/opt/gnu-sed/libexec/gnubin/:$PATH bazel run //application:docker # My docker_build target