kata-deploy: add script for configuring Docker

Before the kata-deploy container image was intended to be
used with only Kubernetes.  This commit adds a script for configuring
Kata to run with Docker.

This assumes > release 1.5 of Kata, as Firecracker is being configured
as well as QEMU based Kata. Note, in order for this to work, Docker must
be configured to use a block-based storage driver.

To succeed, it the following directories must be mounted:
- /opt/kata - this is the location that the kata artifacts are stored
- /run/systemd - for reloading the docker service
- /var/run/dbus - for reloading the docker service
- /etc/docker - for updating the docker configuration (daemon.json)

usage: kata-deploy-kata [install | remove]

Signed-off-by: Eric Ernst <eric.ernst@intel.com>

kata-deploy/Dockerfile

@@ -18,3 +18,6 @@ curl -Lso /bin/kubectl https://storage.googleapis.com/kubernetes-release/release
 chmod +x /bin/kubectl
 
 COPY scripts /opt/kata-artifacts/scripts
+RUN \
+ln -s /opt/kata-artifacts/scripts/kata-deploy-docker.sh /usr/bin/kata-deploy-docker && \
+ln -s /opt/kata-artifacts/scripts/kata-deploy.sh /usr/bin/kata-deploy

kata-deploy/scripts/kata-deploy-docker.sh

@@ -0,0 +1,111 @@
+#!/usr/bin/env bash
+# Copyright (c) 2019 Intel Corporation
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+set -o errexit
+set -o pipefail
+set -o nounset
+
+conf_file="/etc/docker/daemon.json"
+conf_file_backup="${conf_file}.bak"
+snippet="${conf_file}.snip"
+tmp_file="${conf_file}.tmp"
+
+# If we fail for any reason a message will be displayed
+die() {
+        msg="$*"
+        echo "ERROR: $msg" >&2
+        exit 1
+}
+
+function print_usage() {
+	echo "Usage: $0 [install/remove]"
+}
+
+function install_artifacts() {
+	echo "copying kata artifacts onto host"
+	cp -a /opt/kata-artifacts/opt/kata/* /opt/kata/
+	chmod +x /opt/kata/bin/*
+}
+
+function configure_docker() {
+	echo "configuring docker"
+
+	cat <<EOT | tee -a "$snippet"
+{
+  "runtimes": {
+    "kata-qemu": {
+      "path": "/opt/kata/bin/kata-runtime",
+      "runtimeArgs": [ "--kata-config", "/opt/kata/share/defaults/kata-containers/configuration-qemu.toml" ]
+    },
+     "kata-fc": {
+      "path": "/opt/kata/bin/kata-runtime",
+      "runtimeArgs": [ "--kata-config", "/opt/kata/share/defaults/kata-containers/configuration-fc.toml" ]
+    }
+  }
+}
+EOT
+	if [ -f ${conf_file} ]; then
+		cp -n "$conf_file" "$conf_file_backup"
+
+		# Merge in the json snippet:
+		jq -s '[.[] | to_entries] | flatten | reduce .[] as $dot ({}; .[$dot.key] += $dot.value)' "${conf_file}" "${snippet}" > "${tmp_file}"
+		mv "${tmp_file}" "${conf_file}"
+		rm "${snippet}"
+	else
+		mv "${snippet}" "${conf_file}"
+	fi
+
+	systemctl daemon-reload
+	systemctl reload docker
+}
+
+function remove_artifacts() {
+	echo "deleting kata artifacts"
+	rm -rf /opt/kata/
+}
+
+function cleanup_runtime() {
+	echo "cleanup docker"
+	rm -f "${conf_file}"
+
+	if [ -f "${conf_file_backup}" ]; then
+		cp "${conf_file_backup}"  "${conf_file}"
+	fi
+	systemctl daemon-reload
+	systemctl reload docker
+}
+
+function main() {
+	# script requires that user is root
+	euid=`id -u`
+	if [[ $euid -ne 0 ]]; then
+	   die  "This script must be run as root"
+	fi
+
+	action=${1:-}
+	if [ -z $action ]; then
+		print_usage
+		die "invalid arguments"
+	fi
+
+		case $action in
+		install)
+			install_artifacts
+			configure_docker
+			;;
+		remove)
+			cleanup_runtime
+			remove_artifacts
+			;;
+		*)
+			echo invalid arguments
+			print_usage
+			;;
+		esac
+}
+
+
+main $@