Moving docker options to daemon.json

As per the new docker guidelines about customizing the options
like adding registry-mirrors, moving the options to daemon.json

cluster/gce/gci/configure-helper.sh

@@ -1452,40 +1452,105 @@ function create-master-etcd-apiserver-auth {
    fi
 }
 
+function docker-installed {
+    if systemctl cat docker.service &> /dev/null ; then
+        return 0
+    else
+        return 1
+    fi
+}
+
+# util function to add a docker option to daemon.json file only if the daemon.json file is present.
+# accepts only one argument (docker options)
+function addockeropt {
+	DOCKER_OPTS_FILE=/etc/docker/daemon.json
+	if [ "$#" -lt 1 ]; then
+	echo "No arguments are passed while adding docker options. Expect one argument"
+	exit 1
+	elif [ "$#" -gt 1 ]; then
+	echo "Only one argument is accepted"
+	exit 1
+	fi
+	# appends the given input to the docker opts file i.e. /etc/docker/daemon.json file
+	if [ -f "$DOCKER_OPTS_FILE" ]; then
+	cat >> "${DOCKER_OPTS_FILE}" <<EOF
+  $1
+EOF
+	fi
+}
+
+function set_docker_options_non_ubuntu() {
+  # set docker options mtu and storage driver for non-ubuntu
+  # as it is default for ubuntu
+   if [[ -n "$(command -v lsb_release)" && $(lsb_release -si) == "Ubuntu" ]]; then
+      echo "Not adding docker options on ubuntu, as these are default on ubuntu. Bailing out..."
+      return
+   fi
+
+   addockeropt "\"mtu\": 1460,"
+   addockeropt "\"storage-driver\": \"overlay2\","
+
+   echo "setting live restore"
+   # Disable live-restore if the environment variable is set.
+   if [[ "${DISABLE_DOCKER_LIVE_RESTORE:-false}" == "true" ]]; then
+      addockeropt "\"live-restore\": \"false\","
+   fi
+}
+
 function assemble-docker-flags {
-  echo "Assemble docker command line flags"
-  local docker_opts="-p /var/run/docker.pid --iptables=false --ip-masq=false"
+  echo "Assemble docker options"
+
+    # log the contents of the /etc/docker/daemon.json if already exists
+  if [ -f /etc/docker/daemon.json ]; then
+    echo "Contents of the old docker config"
+    cat /etc/docker/daemon.json
+  fi
+
+  cat <<EOF >/etc/docker/daemon.json
+{
+EOF
+
+addockeropt "\"pidfile\": \"/var/run/docker.pid\",
+  \"iptables\": false,
+  \"ip-masq\": false,"
+
+  echo "setting log-level"
   if [[ "${TEST_CLUSTER:-}" == "true" ]]; then
-    docker_opts+=" --log-level=debug"
+    addockeropt "\"log-level\": \"debug\","
   else
-    docker_opts+=" --log-level=warn"
+    addockeropt "\"log-level\": \"warn\","
   fi
+
+  echo "setting network bridge"
   if [[ "${NETWORK_PROVIDER:-}" == "kubenet" || "${NETWORK_PROVIDER:-}" == "cni" ]]; then
     # set docker0 cidr to private ip address range to avoid conflict with cbr0 cidr range
-    docker_opts+=" --bip=169.254.123.1/24"
+    addockeropt "\"bip\": \"169.254.123.1/24\","
   else
-    docker_opts+=" --bridge=cbr0"
+    addockeropt "\"bridge\": \"cbr0\","
   fi
 
+  echo "setting registry mirror"
+  # TODO (vteratipally)  move the registry-mirror completely to /etc/docker/daemon.json
+  local docker_opts=""
   # Decide whether to enable a docker registry mirror. This is taken from
   # the "kube-env" metadata value.
   if [[ -n "${DOCKER_REGISTRY_MIRROR_URL:-}" ]]; then
-    echo "Enable docker registry mirror at: ${DOCKER_REGISTRY_MIRROR_URL}"
-    docker_opts+=" --registry-mirror=${DOCKER_REGISTRY_MIRROR_URL}"
+      docker_opts+="--registry-mirror=${DOCKER_REGISTRY_MIRROR_URL} "
   fi
 
-  # Configure docker logging
-  docker_opts+=" --log-driver=${DOCKER_LOG_DRIVER:-json-file}"
-  docker_opts+=" --log-opt=max-size=${DOCKER_LOG_MAX_SIZE:-10m}"
-  docker_opts+=" --log-opt=max-file=${DOCKER_LOG_MAX_FILE:-5}"
-
-  # Disable live-restore if the environment variable is set.
-
-  if [[ "${DISABLE_DOCKER_LIVE_RESTORE:-false}" == "true" ]]; then
-    docker_opts+=" --live-restore=false"
-  fi
+  set_docker_options_non_ubuntu
 
-  echo "DOCKER_OPTS=\"${docker_opts} ${EXTRA_DOCKER_OPTS:-}\"" > /etc/default/docker
+  echo "setting docker logging options"
+  # Configure docker logging
+  addockeropt "\"log-driver\": \"${DOCKER_LOG_DRIVER:-json-file}\","
+  addockeropt "\"log-opts\": {
+      \"max-size\": \"${DOCKER_LOG_MAX_SIZE:-10m}\",
+      \"max-file\": \"${DOCKER_LOG_MAX_FILE:-5}\"
+    }"
+  cat <<EOF >>/etc/docker/daemon.json
+}
+EOF
+  echo "DOCKER_OPTS=\"${docker_opts}${EXTRA_DOCKER_OPTS:-}\"" > /etc/default/docker
 
   # Ensure TasksMax is sufficient for docker.
   # (https://github.com/kubernetes/kubernetes/issues/51977)