Initial delivery of metrics code (#81)

* Initial delivery of metrics code

* Fix build issues

* Fix build issue with go vet

internal/metrics/exporter_test.go

@@ -0,0 +1,54 @@
+/*
+© Copyright IBM Corporation 2018
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+package metrics
+
+import (
+	"testing"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+func TestCreateGaugeVec(t *testing.T) {
+
+	ch := make(chan *prometheus.Desc)
+	gaugeVec := createGaugeVec("MetricName", "MetricDescription", false)
+	go func() {
+		gaugeVec.Describe(ch)
+	}()
+	description := <-ch
+
+	expected := "Desc{fqName: \"ibmmq_qmgr_MetricName\", help: \"MetricDescription\", constLabels: {}, variableLabels: [qmgr]}"
+	actual := description.String()
+	if actual != expected {
+		t.Errorf("Expected value=%s; actual %s", expected, actual)
+	}
+}
+
+func TestCreateGaugeVec_ObjectLabel(t *testing.T) {
+
+	ch := make(chan *prometheus.Desc)
+	gaugeVec := createGaugeVec("MetricName", "MetricDescription", true)
+	go func() {
+		gaugeVec.Describe(ch)
+	}()
+	description := <-ch
+
+	expected := "Desc{fqName: \"ibmmq_object_MetricName\", help: \"MetricDescription\", constLabels: {}, variableLabels: [object qmgr]}"
+	actual := description.String()
+	if actual != expected {
+		t.Errorf("Expected value=%s; actual %s", expected, actual)
+	}
+}