luci-app-statistics: add dhcpleases

Add the dhcpleases plugin:
https://github.com/openwrt/packages/pull/14204

Added-Frontend-by: Hannu Nyman <hannu.nyman@iki.fi>
Signed-off-by: Nick Hainke <vincent@systemli.org>

[Minor changes to graph: alt_autoscale, precision, label]
Signed-off-by: Hannu Nyman <hannu.nyman@iki.fi>

applications/luci-app-statistics/htdocs/luci-static/resources/statistics/rrdtool/definitions/dhcpleases.js

@@ -0,0 +1,25 @@
+/* Licensed to the public under the Apache License 2.0. */
+
+'use strict';
+'require baseclass';
+
+return baseclass.extend({
+	title: _('DHCP Leases'),
+
+	rrdargs: function(graph, host, plugin, plugin_instance, dtype) {
+		return {
+			title: "%H: DHCP leases",
+			alt_autoscale_max: true,
+			vlabel: "Leases given",
+			number_format: "%3.0lf",
+			data: {
+				types: [ "count" ],
+				options: {
+					count: {
+						title: "Leases"
+					}
+				}
+			}
+		};
+	}
+});

applications/luci-app-statistics/htdocs/luci-static/resources/view/statistics/plugins/dhcpleases.js

@@ -0,0 +1,21 @@
+'use strict';
+'require baseclass';
+'require form';
+
+return baseclass.extend({
+	title: _('DHCP Leases Plugin Configuration'),
+	description: _('The dhcpleases plugin collects information about assigned DHCP leases.'),
+
+	addFormOptions: function(s) {
+		var o;
+
+		o = s.option(form.Flag, 'enable', _('Enable this plugin'));
+
+		o = s.option(form.Value, 'Path', _('DHCP leases file'));
+		o.default = '/tmp/dhcp.leases';
+	},
+
+	configSummary: function(section) {
+		return _('Monitoring DHCP leases enabled');
+	}
+});

applications/luci-app-statistics/root/etc/config/luci_statistics

@@ -86,6 +86,10 @@ config statistics 'collectd_df'
 	option IgnoreSelected '0'
 	option ValuesPercentage '0'
 
+config statistics 'collectd_dhcpleases'
+	option enable '0'
+	option Path '/tmp/dhcp.leases'
+
 config statistics 'collectd_disk'
 	option enable '0'
 	option Disks 'hda1 hdb'

applications/luci-app-statistics/root/usr/share/luci/statistics/plugins/dhcpleases.json

@@ -0,0 +1,9 @@
+{
+	"title": "Dhcpleases",
+	"category": "network",
+	"legend": [
+		[],
+		[],
+		["Path"]
+	]
+}