api: added action for resetting statistics

lib/api/CMakeLists.txt

@@ -35,6 +35,7 @@ set(API_SRC
     actions/paths.cpp
     actions/restart.cpp
     actions/node.cpp
+    actions/stats.cpp
 )
 
 if(WITH_WEB)

lib/api/actions/stats.cpp

@@ -0,0 +1,79 @@
+/** The API ressource for getting and resetting statistics.
+ *
+ * @author Steffen Vogel <stvogel@eonerc.rwth-aachen.de>
+ * @copyright 2014-2019, Institute for Automation of Complex Power Systems, EONERC
+ * @license GNU General Public License (version 3)
+ *
+ * VILLASnode
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *********************************************************************************/
+
+#include <jansson.h>
+
+#include <villas/log.h>
+#include <villas/node.h>
+#include <villas/stats.h>
+#include <villas/super_node.hpp>
+#include <villas/utils.h>
+#include <villas/api/session.hpp>
+#include <villas/api/action.hpp>
+#include <villas/api.hpp>
+
+namespace villas {
+namespace node {
+namespace api {
+
+class StatsAction : public Action  {
+
+public:
+	using Action::Action;
+
+	virtual int execute(json_t *args, json_t **resp)
+	{
+		int ret, reset = 0;
+		json_error_t err;
+
+		ret = json_unpack_ex(args, &err, 0, "{ s?: b }",
+			"reset", &reset
+		);
+		if (ret < 0)
+			return ret;
+
+		struct vlist *nodes = session->getSuperNode()->getNodes();
+
+		for (size_t i = 0; i < vlist_length(nodes); i++) {
+			struct node *n = (struct node *) vlist_at(nodes, i);
+
+			if (n->stats) {
+				if (reset) {
+					stats_reset(n->stats);
+					info("Stats resetted for node %s", node_name(n));
+				}
+			}
+		}
+
+		*resp = json_object();
+
+		return 0;
+	}
+
+};
+
+/* Register actions */
+static ActionPlugin<StatsAction>    p1("stats", "get or reset internal statistics counters");
+
+} /* namespace api */
+} /* namespace node */
+} /* namespace villas */