On plugin pull errors, delete created dirs.

Signed-off-by: Anusha Ragunathan <anusha@docker.com>
(cherry picked from commit 9e4234261c3e4d13f98218a97d7cc6644723e310)
Signed-off-by: Victor Vieux <victorvieux@gmail.com>

plugin/backend_linux.go

@@ -19,6 +19,7 @@ import (
 	"github.com/docker/docker/pkg/stringid"
 	"github.com/docker/docker/plugin/distribution"
 	"github.com/docker/docker/plugin/v2"
+	"github.com/docker/docker/reference"
 	"golang.org/x/net/context"
 )
 
@@ -60,6 +61,29 @@ func (pm *Manager) Inspect(name string) (tp types.Plugin, err error) {
 	return p.PluginObj, nil
 }
 
+func (pm *Manager) pull(ref reference.Named, metaHeader http.Header, authConfig *types.AuthConfig, pluginID string) (types.PluginPrivileges, error) {
+	pd, err := distribution.Pull(ref, pm.registryService, metaHeader, authConfig)
+	if err != nil {
+		logrus.Debugf("error in distribution.Pull(): %v", err)
+		return nil, err
+	}
+
+	if err := distribution.WritePullData(pd, filepath.Join(pm.libRoot, pluginID), true); err != nil {
+		logrus.Debugf("error in distribution.WritePullData(): %v", err)
+		return nil, err
+	}
+
+	tag := distribution.GetTag(ref)
+	p := v2.NewPlugin(ref.Name(), pluginID, pm.runRoot, pm.libRoot, tag)
+	if err := p.InitPlugin(); err != nil {
+		return nil, err
+	}
+	pm.pluginStore.Add(p)
+
+	pm.pluginEventLogger(pluginID, ref.String(), "pull")
+	return p.ComputePrivileges(), nil
+}
+
 // Pull pulls a plugin and computes the privileges required to install it.
 func (pm *Manager) Pull(name string, metaHeader http.Header, authConfig *types.AuthConfig) (types.PluginPrivileges, error) {
 	ref, err := distribution.GetRef(name)
@@ -75,32 +99,21 @@ func (pm *Manager) Pull(name string, metaHeader http.Header, authConfig *types.A
 	}
 
 	pluginID := stringid.GenerateNonCryptoID()
-
-	if err := os.MkdirAll(filepath.Join(pm.libRoot, pluginID), 0755); err != nil {
+	pluginDir := filepath.Join(pm.libRoot, pluginID)
+	if err := os.MkdirAll(pluginDir, 0755); err != nil {
 		logrus.Debugf("error in MkdirAll: %v", err)
 		return nil, err
 	}
 
-	pd, err := distribution.Pull(ref, pm.registryService, metaHeader, authConfig)
+	priv, err := pm.pull(ref, metaHeader, authConfig, pluginID)
 	if err != nil {
-		logrus.Debugf("error in distribution.Pull(): %v", err)
-		return nil, err
-	}
-
-	if err := distribution.WritePullData(pd, filepath.Join(pm.libRoot, pluginID), true); err != nil {
-		logrus.Debugf("error in distribution.WritePullData(): %v", err)
-		return nil, err
-	}
-
-	tag := distribution.GetTag(ref)
-	p := v2.NewPlugin(ref.Name(), pluginID, pm.runRoot, pm.libRoot, tag)
-	if err := p.InitPlugin(); err != nil {
+		if err := os.RemoveAll(pluginDir); err != nil {
+			logrus.Warnf("unable to remove %q from failed plugin pull: %v", pluginDir, err)
+		}
 		return nil, err
 	}
-	pm.pluginStore.Add(p)
 
-	pm.pluginEventLogger(pluginID, name, "pull")
-	return p.ComputePrivileges(), nil
+	return priv, nil
 }
 
 // List displays the list of plugins and associated metadata.