engine: resources: net: test: Add shell test for net resource

This patch adds a shell test for net, which creates a dummy interface
and runs mgmt to bring it up and assign it with an address. It then
checks if the state was applied correctly. Finally, it runs mgmt again
to bring the interface down, and tests that it comes down and stays
down.

test/shell/net.sh

@@ -0,0 +1,109 @@
+#!/bin/bash -e
+
+set -x
+set -o pipefail
+
+# can't test net without sudo
+if ! timeout 1s sudo -A true; then
+	echo "sudo disabled: not checking net"
+	exit
+fi
+
+# values from net0.yaml
+IFACE="mgmtnet0"
+ADDR="192.168.42.13/24"
+
+# bad value used to test events
+BADADDR="10.0.0.254/24"
+
+# is_up returns 0 if the interface ($1) is up, and 1 if it is down.
+function is_up {
+	if [ -z  "$(ip link show $1 up)" ]; then
+		return 1
+	fi
+}
+
+# has_addr returns 0 if the iface ($1) has the addr ($2), and 1 if it doesn't.
+function has_addr {
+	if [ -z "$(ip addr show $1 | grep $2)" ]; then
+		return 1
+	fi
+}
+
+# clean up when we're done
+function cleanup {
+	sudo rm  /etc/systemd/network/mgmt-${IFACE}.network || true
+	sudo ip link del $IFACE || true
+}
+trap cleanup EXIT
+
+# make sure there's somewhere to save the unit file
+sudo mkdir -p /etc/systemd/network
+
+# add a dummy link for tests
+sudo ip link add $IFACE type dummy || true
+
+# run mgmt net res with $IFACE and $ADDR set as above
+sudo -A $timeout --kill-after=55s 50s "$MGMT" run --lang ./net0.mcl --converged-timeout=5 --tmp-prefix &
+pid1=$!
+
+# give the engine time to start up
+sleep 5
+
+# make sure the interface is up
+if ! is_up $IFACE; then
+	echo "failed to bring up $IFACE"
+	exit 1
+fi
+# check the address
+if ! has_addr $IFACE $ADDR; then
+	echo "failed to set addr: $ADDR on $IFACE"
+	exit 1
+fi
+
+# make sure the interface comes up if we set it down
+sudo ip link set down $IFACE
+if ! is_up $IFACE; then
+	echo "failed to bring $IFACE back up"
+	exit 1
+fi
+# make sure the address is replaced if we delete it
+sudo ip addr del $ADDR dev $IFACE
+if ! has_addr $IFACE $ADDR; then
+	echo "failed to replace addr: $ADDR on $IFACE"
+	exit 1
+fi
+
+# add a bad address and make sure it is removed
+sudo ip addr add $BADADDR dev $IFACE
+if has_addr $IFACE $BADADDR; then
+	echo "failed to remove addr: $BADADDR from $IFACE"
+	exit 1
+fi
+
+wait $pid1
+e1=$?
+
+# run mgmt net res with $IFACE state => "down"
+sudo -A $timeout --kill-after=20 15s "$MGMT" run --lang ./net1.mcl --converged-timeout=5 --tmp-prefix &
+
+# give the engine time to start up
+sleep 5
+
+# make sure the interface is down
+if is_up $IFACE; then
+	echo "failed to bring down $IFACE"
+	exit 1
+fi
+
+# bring up the interface and make sure it's brought back down
+sudo ip link set up $IFACE
+if is_up $IFACE; then
+	echo "failed to bring $IFACE back down"
+	exit 1
+fi
+
+wait $pid2
+e2=$?
+
+exit $(($e1+$e2))

test/shell/net0.mcl

@@ -0,0 +1,4 @@
+net "mgmtnet0" {
+	state => "up",
+	addrs => ["192.168.42.13/24",],
+}

test/shell/net1.mcl

@@ -0,0 +1,3 @@
+net "mgmtnet0" {
+	state => "down",
+}