Merge pull request #20198 from cpuguy83/check_drivers_b4_vol_create

Check drivers before vol create
Upstream-commit: 79edcc517231e46d1fa9e03081488527143eefae
Component: engine

components/engine/volume/drivers/adapter.go

@@ -1,9 +1,6 @@
 package volumedrivers
 
-import (
-	"github.com/docker/docker/pkg/plugins"
-	"github.com/docker/docker/volume"
-)
+import "github.com/docker/docker/volume"
 
 type volumeDriverAdapter struct {
 	name  string
@@ -15,21 +12,7 @@ func (a *volumeDriverAdapter) Name() string {
 }
 
 func (a *volumeDriverAdapter) Create(name string, opts map[string]string) (volume.Volume, error) {
-	// First try a Get. For drivers that support Get this will return any
-	// existing volume.
-	v, err := a.proxy.Get(name)
-	if v != nil {
-		return &volumeAdapter{
-			proxy:      a.proxy,
-			name:       v.Name,
-			driverName: a.Name(),
-			eMount:     v.Mountpoint,
-		}, nil
-	}
-
-	// Driver didn't support Get or volume didn't exist. Perform Create.
-	err = a.proxy.Create(name, opts)
-	if err != nil {
+	if err := a.proxy.Create(name, opts); err != nil {
 		return nil, err
 	}
 	return &volumeAdapter{
@@ -63,11 +46,7 @@ func (a *volumeDriverAdapter) List() ([]volume.Volume, error) {
 func (a *volumeDriverAdapter) Get(name string) (volume.Volume, error) {
 	v, err := a.proxy.Get(name)
 	if err != nil {
-		// TODO: remove this hack. Allows back compat with volume drivers that don't support this call
-		if !plugins.IsNotFound(err) {
-			return nil, err
-		}
-		return a.Create(name, nil)
+		return nil, err
 	}
 
 	return &volumeAdapter{

components/engine/volume/store/store.go

@@ -186,12 +186,23 @@ func (s *VolumeStore) create(name, driverName string, opts map[string]string) (v
 		return v, nil
 	}
 
-	logrus.Debugf("Registering new volume reference: driver %s, name %s", driverName, name)
+	// Since there isn't a specified driver name, let's see if any of the existing drivers have this volume name
+	if driverName == "" {
+		v, _ := s.getVolume(name)
+		if v != nil {
+			return v, nil
+		}
+	}
+
+	logrus.Debugf("Registering new volume reference: driver %q, name %q", driverName, name)
 	vd, err := volumedrivers.GetDriver(driverName)
 	if err != nil {
 		return nil, &OpErr{Op: "create", Name: name, Err: err}
 	}
 
+	if v, _ := vd.Get(name); v != nil {
+		return v, nil
+	}
 	return vd.Create(name, opts)
 }
 

components/engine/volume/volume_test.go

@@ -167,10 +167,10 @@ func TestParseMountSpecSplit(t *testing.T) {
 			{"/tmp:/tmp2:ro", "", "/tmp2", "/tmp", "", "", false, false},
 			{"/tmp:/tmp3:rw", "", "/tmp3", "/tmp", "", "", true, false},
 			{"/tmp:/tmp4:foo", "", "", "", "", "", false, true},
-			{"name:/named1", "", "/named1", "", "name", "local", true, false},
+			{"name:/named1", "", "/named1", "", "name", "", true, false},
 			{"name:/named2", "external", "/named2", "", "name", "external", true, false},
 			{"name:/named3:ro", "local", "/named3", "", "name", "local", false, false},
-			{"local/name:/tmp:rw", "", "/tmp", "", "local/name", "local", true, false},
+			{"local/name:/tmp:rw", "", "/tmp", "", "local/name", "", true, false},
 			{"/tmp:tmp", "", "", "", "", "", true, true},
 		}
 	}

components/engine/volume/volume_unix.go

@@ -97,9 +97,6 @@ func ParseMountSpec(spec, volumeDriver string) (*MountPoint, error) {
 	if len(source) == 0 {
 		mp.Source = "" // Clear it out as we previously assumed it was not a name
 		mp.Driver = volumeDriver
-		if len(mp.Driver) == 0 {
-			mp.Driver = DefaultDriverName
-		}
 		// Named volumes can't have propagation properties specified.
 		// Their defaults will be decided by docker. This is just a
 		// safeguard. Don't want to get into situations where named