internal: avoid restart loop on config errors

ban-internal-server/data/www/int2.py

@@ -144,5 +144,9 @@ def run_server(host, port=82):
     httpd.serve_forever()
 
 if __name__ == "__main__":
+    try:
         settings = read_settings('/etc/eterban/settings.ini')
         run_server(settings['ban_server'])
+    except (KeyError, ValueError, configparser.Error) as error:
+        logger.error('Invalid Eterban configuration: %s', error)
+        raise SystemExit(78)

gateway/etc/systemd/system/eterban-internal.service

@@ -7,6 +7,7 @@ Type=simple
 ExecStart=/usr/bin/python3 /usr/share/eterban/eterban_internal.py
 Restart=on-failure
 RestartSec=5
+RestartPreventExitStatus=78
 
 [Install]
 WantedBy=multi-user.target

tests/static-checks.sh

@@ -30,3 +30,14 @@ if [ "$status" -ne 78 ]; then
     echo "switcher without configuration returned $status, expected 78" >&2
     exit 1
 fi
+
+if (cd ban-internal-server/data/www && python3 -c 'from pathlib import Path; p = Path("int2.py"); code = p.read_text().replace("/etc/eterban/settings.ini", "/dev/null"); exec(compile(code, str(p), "exec"))') >/dev/null 2>&1; then
+    echo 'internal service without configuration must fail' >&2
+    exit 1
+else
+    status=$?
+fi
+if [ "$status" -ne 78 ]; then
+    echo "internal service without configuration returned $status, expected 78" >&2
+    exit 1
+fi