Use md5 to generate unique lock names

pkg/util/lock/lock.go

@@ -17,12 +17,12 @@ limitations under the License.
 package lock
 
 import (
+	"crypto/md5"
 	"fmt"
 	"io/ioutil"
 	"os"
 	"os/user"
 	"regexp"
-	"strings"
 	"time"
 
 	"github.com/golang/glog"
@@ -78,13 +78,5 @@ func UserMutexSpec(path string) mutex.Spec {
 
 func getMutexNameForPath(path string) string {
 	// juju requires that names match ^[a-zA-Z][a-zA-Z0-9-]*$", and be under 40 chars long.
-	n := strings.Trim(nonString.ReplaceAllString(path, "-"), "-")
-	// we need to always guarantee an alphanumeric prefix
-	prefix := "m"
-
-	// Prefer the last 40 chars, as paths tend get more specific toward the end
-	if len(n) >= 40 {
-		return prefix + n[len(n)-39:]
-	}
-	return prefix + n
+	return fmt.Sprintf("m%x", md5.Sum([]byte(path)))
 }

pkg/util/lock/lock_test.go

@@ -24,45 +24,46 @@ func TestUserMutexSpec(t *testing.T) {
 	var tests = []struct {
 		description string
 		path        string
-		expected    string
 	}{
 		{
 			description: "standard",
 			path:        "/foo/bar",
-			expected:    "mfoo-bar-test",
 		},
 		{
 			description: "deep directory",
 			path:        "/foo/bar/baz/bat",
-			expected:    "mfoo-bar-baz-bat-test",
 		},
 		{
 			description: "underscores",
 			path:        "/foo_bar/baz",
-			expected:    "mfoo-bar-baz-test",
 		},
 		{
 			description: "starts with number",
 			path:        "/foo/2bar/baz",
-			expected:    "mfoo-2bar-baz-test",
 		},
 		{
 			description: "starts with punctuation",
 			path:        "/.foo/bar",
-			expected:    "mfoo-bar-test",
 		},
 		{
 			description: "long filename",
 			path:        "/very-very-very-very-very-very-very-very-long/bar",
-			expected:    "m-very-very-very-very-very-long-bar-test",
+		},
+		{
+			description: "Windows kubeconfig",
+			path:        `C:\Users\admin/.kube/config`,
+		},
+		{
+			description: "Windows json",
+			path:        `C:\Users\admin\.minikube\profiles\containerd-20191210T212325.7356633-8584\config.json`,
 		},
 	}
 
 	for _, tc := range tests {
 		t.Run(tc.description, func(t *testing.T) {
 			got := UserMutexSpec(tc.path)
-			if got.Name != tc.expected {
-				t.Errorf("%s mutex name = %q, expected %q", tc.path, got.Name, tc.expected)
+			if len(got.Name) > 40 {
+				t.Errorf("%s mutex name is too long", got.Name)
 			}
 		})
 	}