Merge pull request #5 from digitalocean/improvements

Add doc comments, clarify error log messages, use collectors package …

collectors/cluster_usage.go

@@ -159,7 +159,7 @@ func (c *ClusterUsageCollector) Describe(ch chan<- *prometheus.Desc) {
 // cluster usage over to the provided prometheus Metric channel.
 func (c *ClusterUsageCollector) Collect(ch chan<- prometheus.Metric) {
 	if err := c.collect(); err != nil {
-		log.Println("failed collecting metrics:", err)
+		log.Println("failed collecting cluster usage metrics:", err)
 		return
 	}
 

collectors/doc.go

@@ -0,0 +1,3 @@
+// Package collectors provides a number of Prometheus collectors which are
+// capable of retrieving metrics from a Ceph cluster.
+package collectors

collectors/health.go

@@ -312,7 +312,7 @@ func (c *ClusterHealthCollector) Describe(ch chan<- *prometheus.Desc) {
 // It requires the caller to handle synchronization.
 func (c *ClusterHealthCollector) Collect(ch chan<- prometheus.Metric) {
 	if err := c.collect(); err != nil {
-		log.Println("failed collecting metrics:", err)
+		log.Println("failed collecting cluster health metrics:", err)
 		return
 	}
 

collectors/monitors.go

@@ -338,7 +338,7 @@ func (m *MonitorCollector) Describe(ch chan<- *prometheus.Desc) {
 // channel.
 func (m *MonitorCollector) Collect(ch chan<- prometheus.Metric) {
 	if err := m.collect(); err != nil {
-		log.Println("failed collecting metrics:", err)
+		log.Println("failed collecting monitor metrics:", err)
 		return
 	}
 

collectors/pool_usage.go

@@ -175,7 +175,7 @@ func (p *PoolUsageCollector) Describe(ch chan<- *prometheus.Desc) {
 // prometheus channel.
 func (p *PoolUsageCollector) Collect(ch chan<- prometheus.Metric) {
 	if err := p.collect(); err != nil {
-		log.Println("failed collecting metrics:", err)
+		log.Println("failed collecting pool usage metrics:", err)
 		return
 	}
 

exporter.go

@@ -12,6 +12,7 @@
 //   See the License for the specific language governing permissions and
 //   limitations under the License.
 
+// Command ceph_exporter provides a Prometheus exporter for a Ceph cluster.
 package main
 
 import (
@@ -20,7 +21,7 @@ import (
 	"net/http"
 	"sync"
 
-	ceph_collectors "github.com/digitalocean/ceph_exporter/collectors"
+	"github.com/digitalocean/ceph_exporter/collectors"
 
 	"github.com/ceph/go-ceph/rados"
 	"github.com/prometheus/client_golang/prometheus"
@@ -45,10 +46,10 @@ var _ prometheus.Collector = &CephExporter{}
 func NewCephExporter(conn *rados.Conn) *CephExporter {
 	return &CephExporter{
 		collectors: []prometheus.Collector{
-			ceph_collectors.NewClusterUsageCollector(conn),
-			ceph_collectors.NewPoolUsageCollector(conn),
-			ceph_collectors.NewClusterHealthCollector(conn),
-			ceph_collectors.NewMonitorCollector(conn),
+			collectors.NewClusterUsageCollector(conn),
+			collectors.NewPoolUsageCollector(conn),
+			collectors.NewClusterHealthCollector(conn),
+			collectors.NewMonitorCollector(conn),
 		},
 	}
 }