Fix volume driver API compatibility mode (a little)

Signed-off-by: Stephen Rust <srust@blockbridge.com>
(cherry picked from commit c3985bdf797a4526eac5fb0bd92047ac0f8513d9)

From PR #19983

integration-cli/docker_cli_volume_driver_compat_unix_test.go

@@ -24,11 +24,18 @@ func init() {
 	})
 }
 
+type vol struct {
+	Name       string
+	Mountpoint string
+	Opts       map[string]string
+}
+
 type DockerExternalVolumeSuiteCompatV1_1 struct {
-	server *httptest.Server
-	ds     *DockerSuite
-	d      *Daemon
-	ec     *eventCounter
+	server  *httptest.Server
+	ds      *DockerSuite
+	d       *Daemon
+	ec      *eventCounter
+	volList []vol
 }
 
 func (s *DockerExternalVolumeSuiteCompatV1_1) SetUpTest(c *check.C) {
@@ -47,6 +54,7 @@ func (s *DockerExternalVolumeSuiteCompatV1_1) SetUpSuite(c *check.C) {
 
 	type pluginRequest struct {
 		Name string
+		Opts map[string]string
 	}
 
 	type pluginResp struct {
@@ -54,12 +62,6 @@ func (s *DockerExternalVolumeSuiteCompatV1_1) SetUpSuite(c *check.C) {
 		Err        string `json:",omitempty"`
 	}
 
-	type vol struct {
-		Name       string
-		Mountpoint string
-	}
-	var volList []vol
-
 	read := func(b io.ReadCloser) (pluginRequest, error) {
 		defer b.Close()
 		var pr pluginRequest
@@ -94,7 +96,7 @@ func (s *DockerExternalVolumeSuiteCompatV1_1) SetUpSuite(c *check.C) {
 			send(w, err)
 			return
 		}
-		volList = append(volList, vol{Name: pr.Name})
+		s.volList = append(s.volList, vol{Name: pr.Name, Opts: pr.Opts})
 		send(w, nil)
 	})
 
@@ -111,13 +113,13 @@ func (s *DockerExternalVolumeSuiteCompatV1_1) SetUpSuite(c *check.C) {
 			return
 		}
 
-		for i, v := range volList {
+		for i, v := range s.volList {
 			if v.Name == pr.Name {
 				if err := os.RemoveAll(hostVolumePath(v.Name)); err != nil {
 					send(w, fmt.Sprintf(`{"Err": "%v"}`, err))
 					return
 				}
-				volList = append(volList[:i], volList[i+1:]...)
+				s.volList = append(s.volList[:i], s.volList[i+1:]...)
 				break
 			}
 		}
@@ -213,3 +215,20 @@ func (s *DockerExternalVolumeSuiteCompatV1_1) TestExternalVolumeDriverCompatV1_1
 	out, err = s.d.Cmd("volume", "rm", "foo")
 	c.Assert(err, checker.IsNil, check.Commentf(out))
 }
+
+func (s *DockerExternalVolumeSuiteCompatV1_1) TestExternalVolumeDriverCompatOptionsV1_1(c *check.C) {
+	err := s.d.StartWithBusybox()
+	c.Assert(err, checker.IsNil)
+
+	out, err := s.d.Cmd("volume", "create", "--name", "optvol", "--driver", "test-external-volume-driver", "--opt", "opt1=opt1val", "--opt", "opt2=opt2val")
+	c.Assert(err, checker.IsNil, check.Commentf(out))
+
+	out, err = s.d.Cmd("volume", "inspect", "optvol")
+	c.Assert(err, checker.IsNil, check.Commentf(out))
+
+	c.Assert(s.volList[0].Opts["opt1"], checker.Equals, "opt1val")
+	c.Assert(s.volList[0].Opts["opt2"], checker.Equals, "opt2val")
+
+	out, err = s.d.Cmd("volume", "rm", "optvol")
+	c.Assert(err, checker.IsNil, check.Commentf(out))
+}

volume/drivers/adapter.go

@@ -15,7 +15,20 @@ func (a *volumeDriverAdapter) Name() string {
 }
 
 func (a *volumeDriverAdapter) Create(name string, opts map[string]string) (volume.Volume, error) {
-	err := a.proxy.Create(name, opts)
+	// 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 {
 		return nil, err
 	}

volume/store/store.go

@@ -192,9 +192,6 @@ func (s *VolumeStore) create(name, driverName string, opts map[string]string) (v
 		return nil, &OpErr{Op: "create", Name: name, Err: err}
 	}
 
-	if v, err := vd.Get(name); err == nil {
-		return v, nil
-	}
 	return vd.Create(name, opts)
 }