Add metrics from NGINX Plus API version 6 (#281)

Author: lucacome

README.md

@@ -245,6 +245,30 @@ Name | Type | Description | Labels
 `nginxplus_resolver_timedout` | Counter | Total number of timed out request | `resolver` |
 `nginxplus_resolver_unknown` | Counter | Total requests completed with an unknown error | `resolver`|
 
+#### [HTTP Requests Rate Limiting](https://nginx.org/en/docs/http/ngx_http_api_module.html#def_nginx_http_limit_req_zone)
+Name | Type | Description | Labels
+----|----|----|----|
+`nginxplus_limit_request_passed` | Counter | Total number of requests that were neither limited nor accounted as limited | `zone` |
+`nginxplus_limit_request_rejected` | Counter | Total number of requests that were that were rejected | `zone` |
+`nginxplus_limit_request_delayed` | Counter | Total number of requests that were delayed | `zone` |
+`nginxplus_limit_request_rejected_dry_run` | Counter | Total number of requests accounted as rejected in the dry run mode | `zone` |
+`nginxplus_limit_request_delayed_dry_run` | Counter | Total number of requests accounted as delayed in the dry run mode | `zone` |
+
+#### [HTTP Connections Limiting](https://nginx.org/en/docs/http/ngx_http_api_module.html#def_nginx_http_limit_conn_zone)
+Name | Type | Description | Labels
+----|----|----|----|
+`nginxplus_limit_connection_passed` | Counter | Total number of connections that were neither limited nor accounted as limited | `zone` |
+`nginxplus_limit_connection_rejected` | Counter | Total number of connections that were rejected | `zone` |
+`nginxplus_limit_connection_rejected_dry_run` | Counter | Total number of connections accounted as rejected in the dry run mode | `zone` |
+
+
+#### [Stream Connections Limiting](https://nginx.org/en/docs/http/ngx_http_api_module.html#def_nginx_stream_limit_conn_zone)
+Name | Type | Description | Labels
+----|----|----|----|
+`nginxplus_stream_limit_connection_passed` | Counter | Total number of connections that were neither limited nor accounted as limited | `zone` |
+`nginxplus_stream_limit_connection_rejected` | Counter | Total number of connections that were rejected | `zone` |
+`nginxplus_stream_limit_connection_rejected_dry_run` | Counter | Total number of connections accounted as rejected in the dry run mode | `zone` |
+
 Connect to the `/metrics` page of the running exporter to see the complete list of metrics along with their descriptions. Note: to see server zones related metrics you must configure [status zones](https://nginx.org/en/docs/http/ngx_http_status_module.html#status_zone) and to see upstream related metrics you must configure upstreams with a [shared memory zone](https://nginx.org/en/docs/http/ngx_http_upstream_module.html#zone).
 
 ## Troubleshooting

collector/nginx_plus.go

@@ -38,6 +38,9 @@ type NginxPlusCollector struct {
 	streamUpstreamServerMetrics    map[string]*prometheus.Desc
 	locationZoneMetrics            map[string]*prometheus.Desc
 	resolverMetrics                map[string]*prometheus.Desc
+	limitRequestMetrics            map[string]*prometheus.Desc
+	limitConnectionMetrics         map[string]*prometheus.Desc
+	streamLimitConnectionMetrics   map[string]*prometheus.Desc
 	upMetric                       prometheus.Gauge
 	mutex                          sync.Mutex
 	variableLabelNames             VariableLabelNames
@@ -340,6 +343,23 @@ func NewNginxPlusCollector(nginxClient *plusclient.NginxClient, namespace string
 			"timedout": newResolverMetric(namespace, "timedout", "Total number of timed out requests", constLabels),
 			"unknown":  newResolverMetric(namespace, "unknown", "Total requests completed with an unknown error", constLabels),
 		},
+		limitRequestMetrics: map[string]*prometheus.Desc{
+			"passed":           newLimitRequestMetric(namespace, "passed", "Total number of requests that were neither limited nor accounted as limited", constLabels),
+			"delayed":          newLimitRequestMetric(namespace, "delayed", "Total number of requests that were delayed", constLabels),
+			"rejected":         newLimitRequestMetric(namespace, "rejected", "Total number of requests that were that were rejected", constLabels),
+			"delayed_dry_run":  newLimitRequestMetric(namespace, "delayed_dry_run", "Total number of requests accounted as delayed in the dry run mode", constLabels),
+			"rejected_dry_run": newLimitRequestMetric(namespace, "rejected_dry_run", "Total number of requests accounted as rejected in the dry run mode", constLabels),
+		},
+		limitConnectionMetrics: map[string]*prometheus.Desc{
+			"passed":           newLimitConnectionMetric(namespace, "passed", "Total number of connections that were neither limited nor accounted as limited", constLabels),
+			"rejected":         newLimitConnectionMetric(namespace, "rejected", "Total number of connections that were rejected", constLabels),
+			"rejected_dry_run": newLimitConnectionMetric(namespace, "rejected_dry_run", "Total number of connections accounted as rejected in the dry run mode", constLabels),
+		},
+		streamLimitConnectionMetrics: map[string]*prometheus.Desc{
+			"passed":           newStreamLimitConnectionMetric(namespace, "passed", "Total number of connections that were neither limited nor accounted as limited", constLabels),
+			"rejected":         newStreamLimitConnectionMetric(namespace, "rejected", "Total number of connections that were rejected", constLabels),
+			"rejected_dry_run": newStreamLimitConnectionMetric(namespace, "rejected_dry_run", "Total number of connections accounted as rejected in the dry run mode", constLabels),
+		},
 		upMetric: newUpMetric(namespace, constLabels),
 	}
 }
@@ -379,6 +399,15 @@ func (c *NginxPlusCollector) Describe(ch chan<- *prometheus.Desc) {
 	for _, m := range c.resolverMetrics {
 		ch <- m
 	}
+	for _, m := range c.limitRequestMetrics {
+		ch <- m
+	}
+	for _, m := range c.limitConnectionMetrics {
+		ch <- m
+	}
+	for _, m := range c.streamLimitConnectionMetrics {
+		ch <- m
+	}
 }
 
 // Collect fetches metrics from NGINX Plus and sends them to the provided channel.
@@ -683,6 +712,26 @@ func (c *NginxPlusCollector) Collect(ch chan<- prometheus.Metric) {
 		ch <- prometheus.MustNewConstMetric(c.resolverMetrics["unknown"],
 			prometheus.CounterValue, float64(zone.Responses.Unknown), name)
 	}
+
+	for name, zone := range stats.HTTPLimitRequests {
+		ch <- prometheus.MustNewConstMetric(c.limitRequestMetrics["passed"], prometheus.CounterValue, float64(zone.Passed), name)
+		ch <- prometheus.MustNewConstMetric(c.limitRequestMetrics["rejected"], prometheus.CounterValue, float64(zone.Rejected), name)
+		ch <- prometheus.MustNewConstMetric(c.limitRequestMetrics["delayed"], prometheus.CounterValue, float64(zone.Delayed), name)
+		ch <- prometheus.MustNewConstMetric(c.limitRequestMetrics["rejected_dry_run"], prometheus.CounterValue, float64(zone.RejectedDryRun), name)
+		ch <- prometheus.MustNewConstMetric(c.limitRequestMetrics["delayed_dry_run"], prometheus.CounterValue, float64(zone.DelayedDryRun), name)
+	}
+
+	for name, zone := range stats.HTTPLimitConnections {
+		ch <- prometheus.MustNewConstMetric(c.limitConnectionMetrics["passed"], prometheus.CounterValue, float64(zone.Passed), name)
+		ch <- prometheus.MustNewConstMetric(c.limitConnectionMetrics["rejected"], prometheus.CounterValue, float64(zone.Rejected), name)
+		ch <- prometheus.MustNewConstMetric(c.limitConnectionMetrics["rejected_dry_run"], prometheus.CounterValue, float64(zone.RejectedDryRun), name)
+	}
+
+	for name, zone := range stats.StreamLimitConnections {
+		ch <- prometheus.MustNewConstMetric(c.streamLimitConnectionMetrics["passed"], prometheus.CounterValue, float64(zone.Passed), name)
+		ch <- prometheus.MustNewConstMetric(c.streamLimitConnectionMetrics["rejected"], prometheus.CounterValue, float64(zone.Rejected), name)
+		ch <- prometheus.MustNewConstMetric(c.streamLimitConnectionMetrics["rejected_dry_run"], prometheus.CounterValue, float64(zone.RejectedDryRun), name)
+	}
 }
 
 var upstreamServerStates = map[string]float64{
@@ -741,3 +790,15 @@ func newLocationZoneMetric(namespace string, metricName string, docString string
 func newResolverMetric(namespace string, metricName string, docString string, constLabels prometheus.Labels) *prometheus.Desc {
 	return prometheus.NewDesc(prometheus.BuildFQName(namespace, "resolver", metricName), docString, []string{"resolver"}, constLabels)
 }
+
+func newLimitRequestMetric(namespace string, metricName string, docString string, constLabels prometheus.Labels) *prometheus.Desc {
+	return prometheus.NewDesc(prometheus.BuildFQName(namespace, "limit_request", metricName), docString, []string{"zone"}, constLabels)
+}
+
+func newLimitConnectionMetric(namespace string, metricName string, docString string, constLabels prometheus.Labels) *prometheus.Desc {
+	return prometheus.NewDesc(prometheus.BuildFQName(namespace, "limit_connection", metricName), docString, []string{"zone"}, constLabels)
+}
+
+func newStreamLimitConnectionMetric(namespace string, metricName string, docString string, constLabels prometheus.Labels) *prometheus.Desc {
+	return prometheus.NewDesc(prometheus.BuildFQName(namespace, "stream_limit_connection", metricName), docString, []string{"zone"}, constLabels)
+}