feature: exposed rootfs path of the container through inspect command

Signed-off-by: fengzixu <hnustphoenix@gmail.com>

apis/server/container_bridge.go

@@ -25,6 +25,10 @@ import (
 	"github.com/sirupsen/logrus"
 )
 
+const (
+	unknowHostRootPath = "<unknown>"
+)
+
 func (s *Server) createContainer(ctx context.Context, rw http.ResponseWriter, req *http.Request) error {
 	label := util_metrics.ActionCreateLabel
 	defer func(start time.Time) {
@@ -84,6 +88,12 @@ func (s *Server) getContainer(ctx context.Context, rw http.ResponseWriter, req *
 		mounts = append(mounts, *mp)
 	}
 
+	hostRootPath := unknowHostRootPath
+	mergedDir, ok := c.Snapshotter.Data["MergedDir"]
+	if ok {
+		hostRootPath = mergedDir
+	}
+
 	container := types.ContainerJSON{
 		ID:           c.ID,
 		Name:         c.Name,
@@ -105,6 +115,7 @@ func (s *Server) getContainer(ctx context.Context, rw http.ResponseWriter, req *
 		Args:            c.Args,
 		ResolvConfPath:  c.ResolvConfPath,
 		HostnamePath:    c.HostnamePath,
+		HostRootPath:    hostRootPath,
 		HostsPath:       c.HostsPath,
 		Driver:          c.Driver,
 		MountLabel:      c.MountLabel,

apis/swagger.yml

@@ -3484,7 +3484,9 @@ definitions:
       NetworkSettings:
         description: "NetworkSettings exposes the network settings in the API."
         $ref: "#/definitions/NetworkSettings"
-
+      HostRootPath:
+        description: "The rootfs path of the container on the host."
+        type: "string"
   ContainerState:
     type: "object"
     required: [StartedAt, FinishedAt, Pid, ExitCode, Error, OOMKilled, Dead, Paused, Restarting, Running, Status]

test/cli_inspect_test.go

@@ -221,3 +221,25 @@ func (suite *PouchInspectSuite) TestContainerInspectPorts(c *check.C) {
 	data, _ := json.Marshal(containers[0].NetworkSettings.Ports)
 	c.Assert(string(data), check.Equals, "{\"80/tcp\":[{\"HostIp\":\"0.0.0.0\",\"HostPort\":\"8080\"}]}")
 }
+
+func (suite *PouchInspectSuite) TestContainerInspectHostRootPath(c *check.C) {
+	name := "TestContainerInspectHostRootPath"
+	res := command.PouchRun("run", "-d", "--name", name, busyboxImage, "top")
+	defer DelContainerForceMultyTime(c, name)
+	res.Assert(c, icmd.Success)
+
+	hostRootPathOutput := command.PouchRun("inspect", "-f", "{{.HostRootPath}}", name).Stdout()
+	containerOutput := command.PouchRun("inspect", name).Stdout()
+
+	containers := make([]types.ContainerJSON, 1)
+	err := json.Unmarshal([]byte(containerOutput), &containers)
+	if err != nil || len(containers) == 0 {
+		c.Fatal("fail to format container json")
+	}
+
+	if containers[0].GraphDriver == nil {
+		c.Fatal("cannot to find any info of GraphDriver")
+	}
+
+	c.Assert(strings.TrimSpace(hostRootPathOutput), check.Equals, containers[0].GraphDriver.Data["MergedDir"])
+}