Fix error message for long-waiting operations

Get HTTP responses together with error, so that we could get full error
messages. It also fixes some edge cases for success responses.

cluster-autoscaler/cloudprovider/azure/azure_agent_pool.go

@@ -209,15 +209,20 @@ func (as *AgentPool) IncreaseSize(delta int) error {
 	}
 	ctx, cancel := getContextWithCancel()
 	defer cancel()
-	_, err = as.manager.azClient.deploymentsClient.CreateOrUpdate(ctx, as.manager.config.ResourceGroup, newDeploymentName, newDeployment)
 	klog.V(3).Infof("Waiting for deploymentsClient.CreateOrUpdate(%s, %s, %v)", as.manager.config.ResourceGroup, newDeploymentName, newDeployment)
-	if err != nil {
-		return err
+	resp, err := as.manager.azClient.deploymentsClient.CreateOrUpdate(ctx, as.manager.config.ResourceGroup, newDeploymentName, newDeployment)
+	isSuccess, realError := isSuccessHTTPResponse(resp, err)
+	if isSuccess {
+		klog.V(3).Infof("deploymentsClient.CreateOrUpdate(%s, %s, %v) success", as.manager.config.ResourceGroup, newDeploymentName, newDeployment)
+
+		// Update cache after scale success.
+		as.curSize = int64(expectedSize)
+		as.lastRefresh = time.Now()
+		return nil
 	}
 
-	as.curSize = int64(expectedSize)
-	as.lastRefresh = time.Now()
-	return err
+	klog.Errorf("deploymentsClient.CreateOrUpdate for deployment %q failed: %v", newDeploymentName, realError)
+	return realError
 }
 
 // GetVirtualMachines returns list of nodes for the given agent pool.

cluster-autoscaler/cloudprovider/azure/azure_container_service_pool.go

@@ -193,7 +193,16 @@ func (agentPool *ContainerServiceAgentPool) setAKSNodeCount(count int) error {
 		klog.Errorf("Failed to update AKS cluster (%q): %v", agentPool.clusterName, err)
 		return err
 	}
-	return future.WaitForCompletionRef(updateCtx, aksClient.Client)
+
+	err = future.WaitForCompletionRef(updateCtx, aksClient.Client)
+	isSuccess, realError := isSuccessHTTPResponse(future.Response(), err)
+	if isSuccess {
+		klog.V(3).Infof("aksClient.CreateOrUpdate for aks cluster %q success", agentPool.clusterName)
+		return nil
+	}
+
+	klog.Errorf("aksClient.CreateOrUpdate for aks cluster %q failed: %v", agentPool.clusterName, realError)
+	return realError
 }
 
 // setACSNodeCount sets node count for ACS agent pool.
@@ -226,7 +235,16 @@ func (agentPool *ContainerServiceAgentPool) setACSNodeCount(count int) error {
 		klog.Errorf("Failed to update ACS cluster (%q): %v", agentPool.clusterName, err)
 		return err
 	}
-	return future.WaitForCompletionRef(updateCtx, acsClient.Client)
+
+	err = future.WaitForCompletionRef(updateCtx, acsClient.Client)
+	isSuccess, realError := isSuccessHTTPResponse(future.Response(), err)
+	if isSuccess {
+		klog.V(3).Infof("acsClient.CreateOrUpdate for acs cluster %q success", agentPool.clusterName)
+		return nil
+	}
+
+	klog.Errorf("acsClient.CreateOrUpdate for acs cluster %q failed: %v", agentPool.clusterName, realError)
+	return realError
 }
 
 //GetNodeCount returns the count of nodes from the managed agent pool profile

cluster-autoscaler/cloudprovider/azure/azure_fakes.go

@@ -63,7 +63,9 @@ func (client *VirtualMachineScaleSetsClientMock) CreateOrUpdate(ctx context.Cont
 	}
 	client.FakeStore[resourceGroupName][VMScaleSetName] = parameters
 
-	return nil, nil
+	return &http.Response{
+		StatusCode: http.StatusOK,
+	}, nil
 }
 
 // DeleteInstances deletes a set of instances for specified VirtualMachineScaleSet.

cluster-autoscaler/cloudprovider/azure/azure_scale_set.go

@@ -153,15 +153,18 @@ func (scaleSet *ScaleSet) SetScaleSetSize(size int64) error {
 	op.VirtualMachineScaleSetProperties.ProvisioningState = nil
 	updateCtx, updateCancel := getContextWithCancel()
 	defer updateCancel()
-	_, err = scaleSet.manager.azClient.virtualMachineScaleSetsClient.CreateOrUpdate(updateCtx, resourceGroup, scaleSet.Name, op)
-	if err != nil {
-		klog.Errorf("virtualMachineScaleSetsClient.CreateOrUpdate for scale set %q failed: %v", scaleSet.Name, err)
-		return err
+	klog.V(3).Infof("Waiting for virtualMachineScaleSetsClient.CreateOrUpdate(%s)", scaleSet.Name)
+	resp, err := scaleSet.manager.azClient.virtualMachineScaleSetsClient.CreateOrUpdate(updateCtx, resourceGroup, scaleSet.Name, op)
+	isSuccess, realError := isSuccessHTTPResponse(resp, err)
+	if isSuccess {
+		klog.V(3).Infof("virtualMachineScaleSetsClient.CreateOrUpdate(%s) success", scaleSet.Name)
+		scaleSet.curSize = size
+		scaleSet.lastRefresh = time.Now()
+		return nil
 	}
 
-	scaleSet.curSize = size
-	scaleSet.lastRefresh = time.Now()
-	return nil
+	klog.Errorf("virtualMachineScaleSetsClient.CreateOrUpdate for scale set %q failed: %v", scaleSet.Name, realError)
+	return realError
 }
 
 // TargetSize returns the current TARGET size of the node group. It is possible that the

cluster-autoscaler/cloudprovider/azure/azure_util.go

@@ -609,3 +609,22 @@ func checkResourceExistsFromError(err error) (bool, error) {
 	}
 	return false, v
 }
+
+// isSuccessHTTPResponse determines if the response from an HTTP request suggests success
+func isSuccessHTTPResponse(resp *http.Response, err error) (isSuccess bool, realError error) {
+	if err != nil {
+		return false, err
+	}
+
+	if resp != nil {
+		// HTTP 2xx suggests a successful response
+		if 199 < resp.StatusCode && resp.StatusCode < 300 {
+			return true, nil
+		}
+
+		return false, fmt.Errorf("failed with HTTP status code %d", resp.StatusCode)
+	}
+
+	// This shouldn't happen, it only ensures all exceptions are handled.
+	return false, fmt.Errorf("failed with unknown error")
+}

cluster-autoscaler/cloudprovider/azure/azure_util_test.go

@@ -18,9 +18,11 @@ package azure
 
 import (
 	"fmt"
+	"net/http"
 	"testing"
 
 	"github.com/Azure/azure-sdk-for-go/services/compute/mgmt/2018-10-01/compute"
+	"github.com/stretchr/testify/assert"
 )
 
 func TestSplitBlobURI(t *testing.T) {
@@ -124,3 +126,66 @@ func TestGetVMNameIndexWindows(t *testing.T) {
 		t.Fatalf("unexpected error: %s", err)
 	}
 }
+
+func TestIsSuccessResponse(t *testing.T) {
+	tests := []struct {
+		name          string
+		resp          *http.Response
+		err           error
+		expected      bool
+		expectedError error
+	}{
+		{
+			name:          "both resp and err nil should report error",
+			expected:      false,
+			expectedError: fmt.Errorf("failed with unknown error"),
+		},
+		{
+			name: "http.StatusNotFound should report error",
+			resp: &http.Response{
+				StatusCode: http.StatusNotFound,
+			},
+			expected:      false,
+			expectedError: fmt.Errorf("failed with HTTP status code %d", http.StatusNotFound),
+		},
+		{
+			name: "http.StatusInternalServerError should report error",
+			resp: &http.Response{
+				StatusCode: http.StatusInternalServerError,
+			},
+			expected:      false,
+			expectedError: fmt.Errorf("failed with HTTP status code %d", http.StatusInternalServerError),
+		},
+		{
+			name: "http.StatusOK shouldn't report error",
+			resp: &http.Response{
+				StatusCode: http.StatusOK,
+			},
+			expected: true,
+		},
+		{
+			name: "non-nil response error with http.StatusOK should report error",
+			resp: &http.Response{
+				StatusCode: http.StatusOK,
+			},
+			err:           fmt.Errorf("test error"),
+			expected:      false,
+			expectedError: fmt.Errorf("test error"),
+		},
+		{
+			name: "non-nil response error with http.StatusInternalServerError should report error",
+			resp: &http.Response{
+				StatusCode: http.StatusInternalServerError,
+			},
+			err:           fmt.Errorf("test error"),
+			expected:      false,
+			expectedError: fmt.Errorf("test error"),
+		},
+	}
+
+	for _, test := range tests {
+		result, realError := isSuccessHTTPResponse(test.resp, test.err)
+		assert.Equal(t, test.expected, result, "[%s] expected: %v, saw: %v", test.name, result, test.expected)
+		assert.Equal(t, test.expectedError, realError, "[%s] expected: %v, saw: %v", test.name, realError, test.expectedError)
+	}
+}