Added parity status metrics

Signed-off-by: Marcus Noble <github@marcusnoble.co.uk>

collector.go

@@ -0,0 +1,45 @@
+package main
+
+import (
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+type UnraidCollector struct {
+	parityStatusMetric     *prometheus.Desc
+	parityProgressMetric   *prometheus.Desc
+	parityErrorCountMetric *prometheus.Desc
+
+	metrics []prometheus.Metric
+}
+
+func newUnraidCollector() *UnraidCollector {
+	return &UnraidCollector{
+		parityStatusMetric: prometheus.NewDesc("unraid_parity_check_status",
+			"Parity check status of the Unraid array",
+			[]string{"status"},
+			nil,
+		),
+		parityProgressMetric: prometheus.NewDesc("unraid_parity_check_progress",
+			"Parity check progress percentage",
+			nil, nil,
+		),
+		parityErrorCountMetric: prometheus.NewDesc("unraid_parity_check_error_count",
+			"Parity check error count",
+			nil, nil,
+		),
+
+		metrics: []prometheus.Metric{},
+	}
+}
+
+func (collector *UnraidCollector) Describe(ch chan<- *prometheus.Desc) {
+	ch <- collector.parityStatusMetric
+	ch <- collector.parityProgressMetric
+	ch <- collector.parityErrorCountMetric
+}
+
+func (collector *UnraidCollector) Collect(ch chan<- prometheus.Metric) {
+	for _, m := range collector.metrics {
+		ch <- m
+	}
+}