testsuite: cover resource with sdmon.online

Problem: there is no test coverage for the resource module's
behavior when systemd is configured and sdmon is providing
sdmon.online.

Add a sharness script for that.

t/Makefile.am

@@ -198,6 +198,7 @@ TESTSCRIPTS = \
 	t2410-sdexec-memlimit.t \
 	t2411-sdexec-job.t \
 	t2412-sdmon.t \
+	t2413-sdmon-resource.t \
 	t2500-job-attach.t \
 	t2501-job-status.t \
 	t2600-job-shell-rcalc.t \

t/t2413-sdmon-resource.t

@@ -0,0 +1,108 @@
+#!/bin/sh
+# ci=system
+
+test_description='Test flux systemd monitoring'
+
+. $(dirname $0)/sharness.sh
+
+if ! flux version | grep systemd; then
+	skip_all="flux was not built with systemd"
+	test_done
+fi
+if ! systemctl --user show --property Version; then
+	skip_all="user systemd is not running"
+	test_done
+fi
+if ! busctl --user status >/dev/null; then
+	skip_all="user dbus is not running"
+	test_done
+fi
+if ! busctl status >/dev/null; then
+	skip_all="system dbus is not running"
+	test_done
+fi
+
+mkdir -p config
+cat >config/config.toml <<EOT
+[systemd]
+enable = true
+[exec]
+service = "sdexec"
+EOT
+
+test_under_flux 1 full --config-path=$(pwd)/config
+
+flux setattr log-stderr-level 1
+
+groups="flux python ${SHARNESS_TEST_SRCDIR}/scripts/groups.py"
+
+# Usage: start test unit NAME (without service suffix)
+start_test_unit() {
+        local sleep=$(which sleep)
+        flux exec \
+            --service sdexec \
+            --setopt SDEXEC_NAME="$1.service" \
+            $sleep 3600 &
+}
+# Usage: stop_test_unit NAME (without service suffix)
+stop_test_unit() {
+        systemctl --user stop $1
+}
+# Usage: wait_for_none MAXSEC
+wait_for_none() {
+        local retry=$(($1*10))
+        while ! flux module stats sdmon | jq -e ".units == []"; do
+            sleep 0.1
+            retry=$(($retry-1))
+            test $retry -gt 0 || exit 1
+        done
+}
+# Usage: wait_for_some MAXSEC
+wait_for_some() {
+        local retry=$(($1*10))
+        while flux module stats sdmon | jq -e ".units == []"; do
+            sleep 0.1
+            retry=$(($retry-1))
+            test $retry -gt 0 || exit 1
+        done
+}
+
+test_expect_success 'make sure residual test units are not running' '
+        stop_test_unit shell-t2413 2>/dev/null || true
+'
+test_expect_success 'wait for sdmon.online group' '
+	run_timeout 30 $groups waitfor --count=1 sdmon.online
+'
+test_expect_success 'wait for online resource event' '
+	run_timeout 30 flux resource eventlog --wait=online
+'
+test_expect_success 'start a test unit that looks like a job shell' '
+	start_test_unit shell-t2413
+'
+test_expect_success 'wait for module stats to show test unit' '
+        wait_for_some 30
+'
+test_expect_success 'clear dmesg, then reload sdmin, resource, sched-simple' '
+	flux dmesg -C &&
+	flux module remove sched-simple &&
+	flux module remove resource &&
+	flux module reload sdmon &&
+	flux module load resource &&
+	flux module load sched-simple
+'
+test_expect_success 'stop test unit' '
+	stop_test_unit shell-t2413
+'
+test_expect_success 'wait for module stats to show nothing' '
+        wait_for_none 30
+'
+test_expect_success 'wait for online resource event' '
+	run_timeout 30 flux resource eventlog --wait=online
+'
+test_expect_success 'unit cleanup was logged' '
+	flux dmesg -H >dmesg.out &&
+	grep "shell-t2413.service needs cleanup" dmesg.out &&
+	grep "cleanup complete" dmesg.out
+'
+
+test_done