This change is needed to make descriptor lock per pod, in the next commit.
If losetup is called for symlink, path in the output for losetup is resolved,
as a result, we can't distinguish which path the lock is taken.
This patch removes mount.Exec entirely and instead uses the common
utility from k8s.io/utils/exec.
The fake exec implementation found in k8s.io/utils/exec differs a bit
than mount.Exec, with the ability to pre-script expected calls to
Command.CombinedOutput(), so tests that previously relied on a callback
mechanism to produce specific output have been updated to use that
mechanism.
This patch moves fake.go to mount_fake.go, and follows to principle of
always returning a discrete type rather than an Interface. All callers
of "FakeMounter" are changed to instead use "NewFakeMounter()". The
FakeMounter "Log" struct member is changed to not be exported, and
instead only access through a new "GetLog()" method.
The alpha feature for mount containers is unused, and is
superseded by CSI. By removing it, we can remove a lot of unnecessary
code, and also clean up the mount library even more before moving it out
of tree.
`Get` method within the fake clientset returns an object that would not be normally returned when using the real clientset. Reproducer:
```go
package main
import (
v1 "k8s.io/api/core/v1"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
"k8s.io/client-go/kubernetes/fake"
)
func main () {
cm := &v1.ConfigMap{
ObjectMeta: metav1.ObjectMeta{Namespace: metav1.NamespaceSystem, Name: "cm"},
}
client := fake.NewSimpleClientset(cm)
obj, err := client.CoreV1().ConfigMaps("").Get("", metav1.GetOptions{})
if err != nil {
panic(err)
}
fmt.Printf("obj: %#v\n", obj)
}
```
stored under `test.go` of `github.com/kubernetes/kubernetes` (master HEAD) root directory and ran:
```sh
$ go run test.go
obj: &v1.ConfigMap{TypeMeta:v1.TypeMeta{Kind:"", APIVersion:""}, ObjectMeta:v1.ObjectMeta{Name:"cm", GenerateName:"", Namespace:"kube-system", SelfLink:"", UID:"", ResourceVersion:"", Generation:0, CreationTimestamp:v1.Time{Time:time.Time{wall:0x0, ext:0, loc:(*time.Location)(nil)}}, DeletionTimestamp:(*v1.Time)(nil), DeletionGracePeriodSeconds:(*int64)(nil), Labels:map[string]string(nil), Annotations:map[string]string(nil), OwnerReferences:[]v1.OwnerReference(nil), Finalizers:[]string(nil), ClusterName:"", ManagedFields:[]v1.ManagedFieldsEntry(nil)}, Data:map[string]string(nil), BinaryData:map[string][]uint8(nil)}
```
As you can see fake clientset with a "test" configmap is created. When getting the object through the clientset back, I intentionally set the object name to an empty string. I would expect to get an error saying config map "" was not found. However, I get "test" configmap instead.
Reason for that is inside implementation of `filterByNamespaceAndName` private function:
```go
func filterByNamespaceAndName(objs []runtime.Object, ns, name string) ([]runtime.Object, error) {
var res []runtime.Object
for _, obj := range objs {
acc, err := meta.Accessor(obj)
if err != nil {
return nil, err
}
if ns != "" && acc.GetNamespace() != ns {
continue
}
if name != "" && acc.GetName() != name {
continue
}
res = append(res, obj)
}
return res, nil
}
```
When `name` is empty, `name != "" && acc.GetName() != name` condition is false and thus `obj` is consider as a fit.
[1] https://github.com/kubernetes/client-go/blob/master/testing/fixture.go#L481-L493
