[F20] container readme
BUG=None
TEST=None
Change-Id: I302ba845cec200fcb2f1a8a9f01845dfdc734394
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/dev-util/+/3042339
Reviewed-by: Seewai Fu <seewaifu@google.com>
Reviewed-by: C Shapiro <shapiroc@chromium.org>
Commit-Queue: Derek Beckett <dbeckett@chromium.org>
Tested-by: Derek Beckett <dbeckett@chromium.org>
Auto-Submit: Derek Beckett <dbeckett@chromium.org>
diff --git a/test/container/utils/README.md b/test/container/utils/README.md
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+# How to build & run a test in the container (All of these steps are outside chroot)
+
+## Setup the artifacts for build:
+
+1.) cd to
+
+```bash
+/dev/test/container/utils
+```
+2.) Run the following command:
+
+```bash
+export chroot_path=path/to/your/chroot/base && export sysroot_path=build/<a board that you have built> && export output_path=<where in the sysroot you want the artifacts to go> && sh container_prep_caller.sh`
+```
+
+Example:
+```bash
+export chroot_path=/usr/local/google/home/ldap/drive2/chromiumos/chroot && export sysroot_path=build/hana && export output_path=tmp/dockerout && sh container_prep_caller.sh
+```
+
+## Build the container
+
+3.) cd to the output. Example:
+
+```bash
+cd ../chroot/build/hana/tmp/dockerout/
+```
+
+4.) Run:
+
+```bash
+docker build -t testcontainer -f Dockerfile .
+```
+
+## Run the test via testexecservice
+
+5.) cd to `src/platform/dev/test/container/utils`
+
+6.) Run `docker_run.py` with your required args:
+
+**IMPORTANT NOTE 1**: You must create a request.json with a valid test/DUT. See [tauto example](https://source.corp.google.com/chromeos_public/src/platform/dev/src/chromiumos/test/execution/data/tauto.json) and [tast example](https://source.corp.google.com/chromeos_public/src/platform/dev/src/chromiumos/test/execution/data/test.json)
+
+Example of foreground cmd only (pastes the command, you can copy/paste to start it)
+
+```bash
+python3.6 run_docker.py --build=autotest_jul19 --input_json=../../../src/chromiumos/test/execution/data/tauto.json --results=/usr/local/google/home/dbeckett/drive2/cros_2021/chroot/tmp/dockertest --foreground --cmd_only
+```
+
+Example of self running (It launches docker, runs, exits, all in background, provides results dir):
+
+```bash
+python3.6 run_docker.py --build=autotest_jul19 --input_json=../../../src/chromiumos/test/execution/data/tauto.json --results=/usr/local/google/home/dbeckett/drive2/cros_2021/chroot/tmp/dockertest --cmd_only
+```
