fake CSIProxyMounter to enable unit test

[andyzhangx]

Is your feature request related to a problem?/Why is this needed

Describe the solution you'd like in detail

Need to fake CSIProxyMounter, same as fakeMounter, and enable a few unit tests on Windows, current unit tests failed with return fmt.Errorf("could not cast to csi proxy class"

C:\Users\xiazhang\go\src\github.com\kubernetes-csi\csi-driver-smb\pkg\smb>git diff
diff --git a/pkg/smb/nodeserver_test.go b/pkg/smb/nodeserver_test.go
index ecaeab12..f9a9f386 100644
--- a/pkg/smb/nodeserver_test.go
+++ b/pkg/smb/nodeserver_test.go
@@ -22,9 +22,11 @@ import (
        "fmt"
        "os"
        "reflect"
+       "runtime"
        "syscall"
        "testing"

+       "github.com/kubernetes-csi/csi-driver-smb/pkg/mounter"
        "github.com/kubernetes-csi/csi-driver-smb/test/utils/testutil"

        "github.com/container-storage-interface/spec/lib/go/csi"
@@ -198,7 +200,7 @@ func TestNodeExpandVolume(t *testing.T) {
 }

 func TestNodePublishVolume(t *testing.T) {
-       skipIfTestingOnWindows(t)
+       //skipIfTestingOnWindows(t)
        volumeCap := csi.VolumeCapability_AccessMode{Mode: csi.VolumeCapability_AccessMode_MULTI_NODE_MULTI_WRITER}
        errorMountSource := "./error_mount_source"
        alreadyMountedTarget := "./false_is_likely_exist_target"
@@ -284,9 +286,15 @@ func TestNodePublishVolume(t *testing.T) {
        // Setup
        _ = makeDir(alreadyMountedTarget)
        d := NewFakeDriver()
-       fakeMounter := &fakeMounter{}
-       d.mounter = &mount.SafeFormatAndMount{
-               Interface: fakeMounter,
+       if runtime.GOOS == "windows" {
+               csiProxyMounter, _ := mounter.NewCSIProxyMounter()
+               d.mounter = &mount.SafeFormatAndMount{
+                       Interface: csiProxyMounter,
+               }
+       } else {
+               d.mounter = &mount.SafeFormatAndMount{
+                       Interface: &fakeMounter{},
+               }
        }

        for _, test := range tests {

Without fake, there would be panic:

C:\Users\xiazhang\go\src\github.com\kubernetes-csi\csi-driver-smb\pkg\smb>go test -run TestNodePublishVolume
--- FAIL: TestNodePublishVolume (0.00s)
panic: runtime error: invalid memory address or nil pointer dereference [recovered]
        panic: runtime error: invalid memory address or nil pointer dereference
[signal 0xc0000005 code=0x0 addr=0x10 pc=0x8ae83c]

goroutine 22 [running]:
testing.tRunner.func1(0xc000150100)
        c:/go/src/testing/testing.go:874 +0x3aa
panic(0x996b00, 0xeebb70)
        c:/go/src/runtime/panic.go:679 +0x1c0
github.com/kubernetes-csi/csi-driver-smb/pkg/mounter.(*CSIProxyMounter).ExistsPath(0xc000067e10, 0xa51ca5, 0x8, 0x0, 0x38, 0x8)
        C:/Users/xiazhang/go/src/github.com/kubernetes-csi/csi-driver-smb/pkg/mounter/safe_mounter_windows.go:210 +0x17c
github.com/kubernetes-csi/csi-driver-smb/pkg/mounter.(*CSIProxyMounter).IsLikelyNotMountPoint(0xc000067e10, 0xa51ca5, 0x8, 0xc000093420, 0x40cdf0, 0xc00006d640)
        C:/Users/xiazhang/go/src/github.com/kubernetes-csi/csi-driver-smb/pkg/mounter/safe_mounter_windows.go:148 +0xdf
github.com/kubernetes-csi/csi-driver-smb/pkg/smb.(*Driver).ensureMountPoint(0xc000093858, 0xa51ca5, 0x8, 0x1, 0x2, 0xc00006d640)
        C:/Users/xiazhang/go/src/github.com/kubernetes-csi/csi-driver-smb/pkg/smb/nodeserver.go:274 +0x70
github.com/kubernetes-csi/csi-driver-smb/pkg/smb.(*Driver).NodePublishVolume(0xc000093858, 0xb1fe80, 0xc0000720b0, 0xc0000938e8, 0x1, 0xb135c0, 0xc0000c2d70)
        C:/Users/xiazhang/go/src/github.com/kubernetes-csi/csi-driver-smb/pkg/smb/nodeserver.go:71 +0x1f4
github.com/kubernetes-csi/csi-driver-smb/pkg/smb.TestNodePublishVolume(0xc000150100)
        C:/Users/xiazhang/go/src/github.com/kubernetes-csi/csi-driver-smb/pkg/smb/nodeserver_test.go:301 +0x7f1
testing.tRunner(0xc000150100, 0xa7d240)
        c:/go/src/testing/testing.go:909 +0xd0
created by testing.(*T).Run
        c:/go/src/testing/testing.go:960 +0x357
exit status 2
FAIL    github.com/kubernetes-csi/csi-driver-smb/pkg/smb        1.950s

Another way is use real CSIProxyMounter, and run csi-proxy.exe on Windows before running unit tests.
follow guide here:

• https://github.com/kubernetes-csi/csi-proxy/tree/master#command-line-options
• https://github.com/kubernetes-csi/csi-proxy/blob/25491d0543e53381aab69ee5e5fa114182787b43/cmd/csi-proxy/main.go#L22-L24

Or run as a service using nssm:

• https://github.com/Azure/aks-engine/blob/master/parts/k8s/windowscsiproxyfunc.ps1

Describe alternatives you've considered

Additional context

[boddumanohar]

/assign

[boddumanohar]

Created a PR that runs CSI-Proxy as a background job. I also tried to run with NSSM but I am getting this error:

Run .\hack\start-csi-proxy.ps1
using the .exe .\nssm-2.24\win64\nssm.exe
Service "csi-proxy" installed successfully!
csi-proxy: Unexpected status SERVICE_STOPPED in response to START control.

I believe that windows runners in Github actions has some issues when running a process with Services.msc.

[boddumanohar]

I believe this is fixed by #122