fix: SubApp issue #68 (by @steidl, thxalot), synchronous --stop operation to prevent DB corruption

templates/etc/systemd/user/subapp.service.j2

@@ -8,7 +8,26 @@ Type=forking
 Restart=no
 Environment="PERL5LIB=/usr/local/perl/"
 ExecStart=/usr/bin/perl -I /usr/local/perl/ /usr/local/bin/subapp_bagit.pl --config-file {{ vault_subapp_vars.files.subapp.path }} --start
-ExecStop=/usr/bin/perl -I /usr/local/perl/ /usr/local/bin/subapp_bagit.pl --config-file {{ vault_subapp_vars.files.subapp.path }} --stop
+ExecStop=/usr/bin/perl -I /usr/local/perl/ /usr/local/bin/subapp_bagit.pl --config-file {{ vault_subapp_vars.files.subapp.path }} --stop \;
+ExecStop=/bin/bash -c '\
+    PID=$(cat /run/subapp/subapp_bagit.pid); \
+    if [[ ! "$PID" =~ ^[0-9]+$ ]]; then \
+        echo "something broke, no valid PID for submission application daemon"; \
+        exit 1; \
+    fi; \
+    echo "sending --stop to submission application daemon" | systemd-cat -p info; \
+    /usr/bin/perl -I /usr/local/perl/ /usr/local/bin/subapp_bagit.pl --config-file {{ vault_subapp_vars.files.subapp.path }} --stop; \
+    echo " waiting for submission application daemon to finish" | systemd-cat -p info; \
+    while true; do \
+        ps -p $PID > /dev/null; \
+        if [[ $? != 0 ]]; then \
+            break; \
+        fi; \
+        echo "submission application daemon is still running, waiting another 5 seconds" | systemd-cat -p warning; \
+        sleep 5; \
+    done; \
+    echo "submission application daemon stopped" | systemd-cat -p info'
+
 User={{ vault_subapp_user }}
 Group={{ vault_subapp_group }}
 # EXAMPLE: TimeoutSec=600