use contexts with timeouts in scale set GET calls

Author: marwanad

cluster-autoscaler/cloudprovider/azure/azure_scale_set.go

@@ -174,7 +174,7 @@ func (scaleSet *ScaleSet) getVMSSInfo() (compute.VirtualMachineScaleSet, *retry.
 }
 
 func (scaleSet *ScaleSet) getAllVMSSInfo() ([]compute.VirtualMachineScaleSet, *retry.Error) {
-	ctx, cancel := getContextWithCancel()
+	ctx, cancel := getContextWithTimeout(3 * time.Minute)
 	defer cancel()
 
 	resourceGroup := scaleSet.manager.config.ResourceGroup
@@ -339,7 +339,7 @@ func (scaleSet *ScaleSet) IncreaseSize(delta int) error {
 // GetScaleSetVms returns list of nodes for the given scale set.
 func (scaleSet *ScaleSet) GetScaleSetVms() ([]compute.VirtualMachineScaleSetVM, *retry.Error) {
 	klog.V(4).Infof("GetScaleSetVms: starts")
-	ctx, cancel := getContextWithCancel()
+	ctx, cancel := getContextWithTimeout(3 * time.Minute)
 	defer cancel()
 
 	resourceGroup := scaleSet.manager.config.ResourceGroup

cluster-autoscaler/cloudprovider/azure/azure_util.go

@@ -29,6 +29,7 @@ import (
 	"sort"
 	"strconv"
 	"strings"
+	"time"
 
 	"github.com/Azure/azure-sdk-for-go/services/compute/mgmt/2019-12-01/compute"
 	azStorage "github.com/Azure/azure-sdk-for-go/storage"
@@ -597,6 +598,10 @@ func getContextWithCancel() (context.Context, context.CancelFunc) {
 	return context.WithCancel(context.Background())
 }
 
+func getContextWithTimeout(timeout time.Duration) (context.Context, context.CancelFunc) {
+	return context.WithTimeout(context.Background(), timeout)
+}
+
 // checkExistsFromError inspects an error and returns a true if err is nil,
 // false if error is an autorest.Error with StatusCode=404 and will return the
 // error back if error is another status code or another type of error.