Fix a bug in validating node existence.

pkg/cloudprovider/providers/azure/BUILD

@@ -63,6 +63,7 @@ go_test(
         "azure_loadbalancer_test.go",
         "azure_test.go",
         "azure_util_test.go",
+        "azure_wrap_test.go",
     ],
     importpath = "k8s.io/kubernetes/pkg/cloudprovider/providers/azure",
     library = ":go_default_library",
@@ -71,6 +72,7 @@ go_test(
         "//pkg/kubelet/apis:go_default_library",
         "//vendor/github.com/Azure/azure-sdk-for-go/arm/compute:go_default_library",
         "//vendor/github.com/Azure/azure-sdk-for-go/arm/network:go_default_library",
+        "//vendor/github.com/Azure/go-autorest/autorest:go_default_library",
         "//vendor/github.com/Azure/go-autorest/autorest/to:go_default_library",
         "//vendor/github.com/stretchr/testify/assert:go_default_library",
         "//vendor/k8s.io/api/core/v1:go_default_library",

pkg/cloudprovider/providers/azure/azure_wrap.go

@@ -35,7 +35,10 @@ func checkResourceExistsFromError(err error) (bool, error) {
 		return true, nil
 	}
 	v, ok := err.(autorest.DetailedError)
-	if ok && v.StatusCode == http.StatusNotFound {
+	if !ok {
+		return false, err
+	}
+	if v.StatusCode == http.StatusNotFound {
 		return false, nil
 	}
 	return false, v

pkg/cloudprovider/providers/azure/azure_wrap_test.go

@@ -0,0 +1,53 @@
+/*
+Copyright 2016 The Kubernetes Authors.
+
+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 azure
+
+import (
+	"fmt"
+	"net/http"
+	"reflect"
+	"testing"
+
+	"github.com/Azure/go-autorest/autorest"
+)
+
+func TestExtractNotFound(t *testing.T) {
+	notFound := autorest.DetailedError{StatusCode: http.StatusNotFound}
+	otherHTTP := autorest.DetailedError{StatusCode: http.StatusForbidden}
+	otherErr := fmt.Errorf("other error")
+
+	tests := []struct {
+		err         error
+		expectedErr error
+		exists      bool
+	}{
+		{nil, nil, true},
+		{otherErr, otherErr, false},
+		{notFound, nil, false},
+		{otherHTTP, otherHTTP, false},
+	}
+
+	for _, test := range tests {
+		exists, err := checkResourceExistsFromError(test.err)
+		if test.exists != exists {
+			t.Errorf("expected: %v, saw: %v", test.exists, exists)
+		}
+		if !reflect.DeepEqual(test.expectedErr, err) {
+			t.Errorf("expected err: %v, saw: %v", test.expectedErr, err)
+		}
+	}
+}