helm chart fixes (#102)

* Adding Error Counter Metric

* Adding Semver Prefix and fix typo

deploy/charts/version-checker/Chart.yaml

@@ -1,8 +1,8 @@
 apiVersion: v1
 appVersion: "v0.2.2"
-version: 0.2.3
+version: v0.2.3
 description: A Helm chart for version-checker
-home: https://github.com/jetstack/verison-checker
+home: https://github.com/jetstack/version-checker
 name: version-checker
 maintainers:
 - name: davidcollom

pkg/metrics/metrics.go

@@ -22,6 +22,7 @@ type Metrics struct {
 
 	registry              *prometheus.Registry
 	containerImageVersion *prometheus.GaugeVec
+	containerImageErrors  *prometheus.CounterVec
 	log                   *logrus.Entry
 
 	// container cache stores a cache of a container's current image, version,
@@ -47,14 +48,26 @@ func New(log *logrus.Entry) *Metrics {
 			"namespace", "pod", "container", "image", "current_version", "latest_version",
 		},
 	)
+	containerImageErrors := prometheus.NewCounterVec(
+		prometheus.CounterOpts{
+			Namespace: "version_checker",
+			Name:      "image_failures",
+			Help:      "Where the version-checker was unable to get the latest upstream registry version",
+		},
+		[]string{
+			"namespace", "pod", "container", "image",
+		},
+	)
 
 	registry := prometheus.NewRegistry()
 	registry.MustRegister(containerImageVersion)
+	registry.MustRegister(containerImageErrors)
 
 	return &Metrics{
 		log:                   log.WithField("module", "metrics"),
 		registry:              registry,
 		containerImageVersion: containerImageVersion,
+		containerImageErrors:  containerImageErrors,
 		containerCache:        make(map[string]cacheItem),
 	}
 }