Add metric to monitor all licenses in a HA setup (#153)

* Add metric and scraping for licenses endpoint

* Fix build issues

artifactory/system.go

@@ -9,9 +9,10 @@ import (
 )
 
 const (
-	pingEndpoint    = "system/ping"
-	versionEndpoint = "system/version"
-	licenseEndpoint = "system/license"
+	pingEndpoint     = "system/ping"
+	versionEndpoint  = "system/version"
+	licenseEndpoint  = "system/license"
+	licensesEndpoint = "system/licenses"
 )
 
 type HealthStatus struct {
@@ -65,7 +66,7 @@ func (c *Client) FetchBuildInfo() (BuildInfo, error) {
 	return buildInfo, nil
 }
 
-// LicenseInfo represents API respond from license endpoint
+// LicenseInfo represents API response from license endpoint
 type LicenseInfo struct {
 	Type         string `json:"type"`
 	ValidThrough string `json:"validThrough"`
@@ -117,11 +118,40 @@ func (c *Client) FetchLicense() (LicenseInfo, error) {
 	}
 	licenseInfo.NodeId = resp.NodeId
 	if err := json.Unmarshal(resp.Body, &licenseInfo); err != nil {
-		c.logger.Error("There was an issue when try to unmarshal licenseInfo respond")
+		c.logger.Error("There was an issue when trying to unmarshal licenseInfo response")
 		return licenseInfo, &UnmarshalError{
 			message:  err.Error(),
 			endpoint: licenseEndpoint,
 		}
 	}
 	return licenseInfo, nil
 }
+
+// LicensesInfo represents API response from licenses endpoint
+type LicensesInfo struct {
+	Licenses []struct {
+		LicenseInfo
+		NodeId       string `json:"nodeId"`
+		NodeUrl      string `json:"nodeUrl"`
+		LicenseHash  string `json:"licenseHash"`
+		Expired      bool   `json:"expired"`
+	} `json:"licenses"`
+}
+
+// FetchLicenses makes the API call to licenses endpoint and returns LicensesInfo
+func (c *Client) FetchLicenses() (LicensesInfo, error) {
+	var licensesInfo LicensesInfo
+	c.logger.Debug("Fetching HA licenses stats")
+	resp, err := c.FetchHTTP(licensesEndpoint)
+	if err != nil {
+		return licensesInfo, err
+	}
+	if err := json.Unmarshal(resp.Body, &licensesInfo); err != nil {
+		c.logger.Error("There was an issue when trying to unmarshal licensesInfo response")
+		return licensesInfo, &UnmarshalError{
+			message:  err.Error(),
+			endpoint: licensesEndpoint,
+		}
+	}
+	return licensesInfo, nil
+}

collector/collector.go

@@ -51,9 +51,10 @@ var (
 	}
 
 	systemMetrics = metrics{
-		"healthy": newMetric("healthy", "system", "Is Artifactory working properly (1 = healthy).", defaultLabelNames),
-		"version": newMetric("version", "system", "Version and revision of Artifactory as labels.", append([]string{"version", "revision"}, defaultLabelNames...)),
-		"license": newMetric("license", "system", "License type and expiry as labels, seconds to expiration as value", append([]string{"type", "licensed_to", "expires"}, defaultLabelNames...)),
+		"healthy":  newMetric("healthy", "system", "Is Artifactory working properly (1 = healthy).", defaultLabelNames),
+		"version":  newMetric("version", "system", "Version and revision of Artifactory as labels.", append([]string{"version", "revision"}, defaultLabelNames...)),
+		"license":  newMetric("license", "system", "License type and expiry as labels, seconds to expiration as value", append([]string{"type", "licensed_to", "expires"}, defaultLabelNames...)),
+		"licenses": newMetric("licenses", "system", "License type and expiry as labels, seconds to expiration as value", append([]string{"type", "valid_through", "licensed_to", "node_url", "license_hash", "expires"}, defaultLabelNames...)),
 	}
 
 	artifactsMetrics = metrics{
@@ -145,6 +146,11 @@ func (e *Exporter) scrape(ch chan<- prometheus.Metric) (up float64) {
 		return 0
 	}
 
+	// Collect and export system HA licenses metrics
+	if err := e.exportSystemHALicenses(ch); err != nil {
+		return 0
+	}
+
 	// Fetch Storage Info stats and register them
 	storageInfo, err := e.client.FetchStorageInfo()
 	if err != nil {

collector/system.go

@@ -1,6 +1,8 @@
 package collector
 
 import (
+	"strconv"
+
 	"github.com/prometheus/client_golang/prometheus"
 )
 
@@ -79,3 +81,40 @@ func (e *Exporter) exportSystem(ch chan<- prometheus.Metric) error {
 
 	return nil
 }
+
+func (e *Exporter) exportSystemHALicenses(ch chan<- prometheus.Metric) error {
+	licensesInfo, err := e.client.FetchLicenses()
+	if err != nil {
+		e.logger.Error(
+			"Couldn't scrape Artifactory when fetching system/licenses",
+			"err", err.Error(),
+		)
+		e.totalAPIErrors.Inc()
+		return err
+	}
+
+	for _, licenseInfo := range licensesInfo.Licenses {
+		licenseValSec, err := licenseInfo.ValidSeconds()
+		if err != nil {
+			e.logger.Warn(
+				"Couldn't get Artifactory license validity",
+				"err", err.Error(),
+			) // To preserve the operation, we do nothing but log the event,
+		}
+		metric := systemMetrics["licenses"]
+		ch <- prometheus.MustNewConstMetric(
+			metric,
+			prometheus.GaugeValue,
+			float64(licenseValSec), // Prometheus expects a float type.
+			licenseInfo.TypeNormalized(),
+			licenseInfo.ValidThrough,
+			licenseInfo.LicensedTo,
+			licenseInfo.NodeUrl,
+			licenseInfo.LicenseHash,
+			strconv.FormatBool(licenseInfo.Expired),
+			licenseInfo.NodeId,
+		)
+	}
+
+	return nil
+}