Molecule container for running Molecule

Add own Dockerfile and build script for creating
customized molecule runner image from Molecule image
provided by https://quay.io/repository/ansible/molecule.

Customization enables running of molecule container with
current host's user to avoid root owned files bloating
to developer's machine.

Add wrapper script molecule.sh to utilize custom image
and suitable for testing offline-installer roles.

Issue-ID: OOM-1768

Change-Id: I14ed75decb8fa637c044675543de56f1c0796271
Signed-off-by: Samuli Silvius <s.silvius@partner.samsung.com>
diff --git a/ansible/test/molecule-docker/Dockerfile b/ansible/test/molecule-docker/Dockerfile
new file mode 100644
index 0000000..e4207f2
--- /dev/null
+++ b/ansible/test/molecule-docker/Dockerfile
@@ -0,0 +1,20 @@
+FROM quay.io/ansible/molecule:2.20
+
+ARG USER_ID
+ARG GROUP_ID
+ARG DOCKER_GROUP_ID
+
+# When user/group provided, create user to have matching ids (for the host user)
+# to avoid this docker writing files as root owned
+RUN if [ ${USER_ID:-0} -ne 0 ] && [ ${GROUP_ID:-0} -ne 0 ]; then \
+    # shadow needed for addgroup
+    # sshpass needed for accessing docker_host (localhost) with ssh and without password prompt
+    apk --no-cache add shadow sshpass && \
+    addgroup -g ${GROUP_ID} molecule && \
+    adduser -D -u ${USER_ID} -G molecule molecule && \
+    # Add user to same docker group as in docker_host to be able to use docker driver as sudo
+    groupadd docker-host -g ${DOCKER_GROUP_ID} && \
+    usermod -aG ${DOCKER_GROUP_ID} molecule \
+;fi
+
+USER molecule