Made NewCustomMetrics() idempotent wrt Prometheus registration. Fixed unit tests by plugging CustomMetrics objects into the *clients* they allocate and use.

Author: jweite-amazon

pkg/cloud/affinity_groups_test.go

@@ -88,7 +88,8 @@ var _ = Describe("AffinityGroup Unit Tests", func() {
 			// Make the created VM go away quickly by force stopping it.
 			p := realCSClient.VirtualMachine.NewStopVirtualMachineParams(*dummies.CSMachine1.Spec.InstanceID)
 			p.SetForced(true)
-			Ω(realCSClient.VirtualMachine.StopVirtualMachine(p)).Should(Succeed())
+			_, err := realCSClient.VirtualMachine.StopVirtualMachine(p)
+			Ω(err).ShouldNot(HaveOccurred())
 		})
 
 		It("Creates and deletes an affinity group.", func() {

pkg/cloud/client.go

@@ -94,6 +94,7 @@ func (origC *client) NewClientFromSpec(cfg Config) (Client, error) {
 	// comments for more details
 	newC.cs = cloudstack.NewAsyncClient(newC.config.APIURL, newC.config.APIKey, newC.config.SecretKey, newC.config.VerifySSL)
 	newC.csAsync = cloudstack.NewClient(newC.config.APIURL, newC.config.APIKey, newC.config.SecretKey, newC.config.VerifySSL)
+	newC.customMetrics = metrics.NewCustomMetrics()
 
 	_, err := newC.cs.APIDiscovery.ListApis(newC.cs.APIDiscovery.NewListApisParams())
 	if err != nil && strings.Contains(strings.ToLower(err.Error()), "i/o timeout") {
@@ -103,6 +104,6 @@ func (origC *client) NewClientFromSpec(cfg Config) (Client, error) {
 }
 
 func NewClientFromCSAPIClient(cs *cloudstack.CloudStackClient) Client {
-	c := &client{cs: cs, csAsync: cs}
+	c := &client{cs: cs, csAsync: cs, customMetrics: metrics.NewCustomMetrics()}
 	return c
 }

pkg/metrics/metrics.go

@@ -39,7 +39,14 @@ func NewCustomMetrics() AcsCustomMetrics {
 		},
 		[]string{"acs_error_code"},
 	)
-	crtlmetrics.Registry.MustRegister(customMetrics.acsReconciliationErrorCount)
+	if err := crtlmetrics.Registry.Register(customMetrics.acsReconciliationErrorCount); err != nil {
+		if are, ok := err.(prometheus.AlreadyRegisteredError); ok {
+			customMetrics.acsReconciliationErrorCount = are.ExistingCollector.(*prometheus.CounterVec)
+		} else {
+			// Something else went wrong!
+			panic(err)
+		}
+	}
 
 	// ACS standard error messages of the form "CloudStack API error 431 (CSExceptionErrorCode: 9999):..."
 	//  This regexp is used to extract CSExceptionCodes from the message.