feature: add snapshotter info in container json

Signed-off-by: Michael Wan <[email protected]>

Author: HusterWan

apis/server/container_bridge.go

@@ -315,18 +315,17 @@ func (s *Server) getContainer(ctx context.Context, rw http.ResponseWriter, req *
 	}
 
 	container := types.ContainerJSON{
-		ID:         meta.ID,
-		Name:       meta.Name,
-		Image:      meta.Config.Image,
-		Created:    meta.Created,
-		State:      meta.State,
-		Config:     meta.Config,
-		HostConfig: meta.HostConfig,
+		ID:          meta.ID,
+		Name:        meta.Name,
+		Image:       meta.Config.Image,
+		Created:     meta.Created,
+		State:       meta.State,
+		Config:      meta.Config,
+		HostConfig:  meta.HostConfig,
+		Snapshotter: meta.Snapshotter,
 		GraphDriver: &types.GraphDriverData{
-			Name: "overlay2",
-			Data: map[string]string{
-				"BaseFS": meta.BaseFS,
-			},
+			Name: meta.Snapshotter.Name,
+			Data: meta.Snapshotter.Data,
 		},
 	}
 

apis/swagger.yml

@@ -2808,6 +2808,8 @@ definitions:
         x-nullable: true
       Config:
         $ref: "#/definitions/ContainerConfig"
+      Snapshotter:
+        $ref: "#/definitions/SnapshotterData"
       GraphDriver:
         $ref: "#/definitions/GraphDriverData"
       Mounts:
@@ -2902,6 +2904,20 @@ definitions:
     type: "string"
     enum: ["created", "running", "stopped", "paused", "restarting", "removing", "exited", "dead"]
 
+  SnapshotterData:
+    description: "Information about a container's snapshotter."
+    type: "object"
+    required: [Name, Data]
+    properties:
+      Name:
+        type: "string"
+        x-nullable: false
+      Data:
+        type: "object"
+        x-nullable: false
+        additionalProperties:
+          type: "string"
+
   GraphDriverData:
     description: "Information about a container's graph driver."
     type: "object"

apis/types/container_json.go

@@ -9,6 +9,7 @@ import (
 	"github.com/alibaba/pouch/pkg/jsonstream"
 
 	"github.com/containerd/containerd"
+	"github.com/containerd/containerd/mount"
 	"github.com/containerd/containerd/snapshots"
 	"github.com/opencontainers/image-spec/specs-go/v1"
 )
@@ -73,4 +74,7 @@ type SnapshotAPIClient interface {
 	GetSnapshot(ctx context.Context, id string) (snapshots.Info, error)
 	// RemoveSnapshot removes the snapshot by id.
 	RemoveSnapshot(ctx context.Context, id string) error
+	// GetMounts returns the mounts for the active snapshot transaction identified
+	// by key.
+	GetMounts(ctx context.Context, id string) ([]mount.Mount, error)
 }

apis/types/graph_driver_data.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 
 	"github.com/containerd/containerd/leases"
+	"github.com/containerd/containerd/mount"
 	"github.com/containerd/containerd/platforms"
 	"github.com/containerd/containerd/snapshots"
 	"github.com/opencontainers/image-spec/identity"
@@ -62,3 +63,17 @@ func (c *Client) RemoveSnapshot(ctx context.Context, id string) error {
 
 	return service.Remove(ctx, id)
 }
+
+// GetMounts returns the mounts for the active snapshot transaction identified
+// by key.
+func (c *Client) GetMounts(ctx context.Context, id string) ([]mount.Mount, error) {
+	wrapperCli, err := c.Get(ctx)
+	if err != nil {
+		return nil, fmt.Errorf("failed to get a containerd grpc client: %v", err)
+	}
+
+	service := wrapperCli.client.SnapshotService(defaultSnapshotterName)
+	defer service.Close()
+
+	return service.Mounts(ctx, id)
+}

apis/types/snapshotter_data.go

@@ -409,6 +409,20 @@ func (mgr *ContainerManager) Create(ctx context.Context, name string, config *ty
 		return nil, err
 	}
 
+	// Get snapshot UpperDir
+	var upperDir string
+	mounts, err := mgr.Client.GetMounts(ctx, id)
+	if err != nil {
+		return nil, err
+	} else if len(mounts) != 1 {
+		return nil, fmt.Errorf("failed to get snapshot %s mounts: not equals one", id)
+	}
+	for _, opt := range mounts[0].Options {
+		if strings.HasPrefix(opt, "upperdir=") {
+			upperDir = strings.TrimPrefix(opt, "upperdir=")
+		}
+	}
+
 	// set lxcfs binds
 	if config.HostConfig.EnableLxcfs && lxcfs.IsLxcfsEnabled {
 		config.HostConfig.Binds = append(config.HostConfig.Binds, lxcfs.LxcfsParentDir+":/var/lib/lxc:shared")
@@ -470,6 +484,17 @@ func (mgr *ContainerManager) Create(ctx context.Context, name string, config *ty
 		return nil, err
 	}
 
+	// set snapshotter for container
+	// TODO(ziren): now we only support overlayfs
+	meta.Snapshotter = &types.SnapshotterData{
+		Name: "overlayfs",
+		Data: map[string]string{},
+	}
+
+	if upperDir != "" {
+		meta.Snapshotter.Data["UpperDir"] = upperDir
+	}
+
 	container := &Container{
 		meta: meta,
 	}
@@ -627,6 +652,9 @@ func (mgr *ContainerManager) createContainerdContainer(ctx context.Context, c *C
 		}
 		c.meta.State.Pid = int64(pid)
 		c.meta.State.ExitCode = 0
+
+		// set Snapshot MergedDir
+		c.meta.Snapshotter.Data["MergedDir"] = c.meta.BaseFS
 	} else {
 		c.meta.State.FinishedAt = time.Now().UTC().Format(utils.TimeLayout)
 		c.meta.State.Error = err.Error()
@@ -1261,6 +1289,12 @@ func (mgr *ContainerManager) markStoppedAndRelease(c *Container, m *ctrd.Message
 		}
 	}
 
+	// unset Snapshot MergedDir. Stop a container will
+	// delete the containerd container, the merged dir
+	// will also be deleted, so we should unset the
+	// container's MergedDir.
+	c.meta.Snapshotter.Data["MergedDir"] = ""
+
 	// update meta
 	if err := c.Write(mgr.Store); err != nil {
 		logrus.Errorf("failed to update meta: %v", err)

ctrd/interface.go

@@ -104,6 +104,11 @@ type ContainerMeta struct {
 	// exec ids
 	ExecIds string `json:"ExecIDs,omitempty"`
 
+	// Snapshotter, GraphDriver is same, keep both
+	// just for compatibility
+	// snapshotter informations of container
+	Snapshotter *types.SnapshotterData `json:"Snapshotter,omitempty"`
+
 	// graph driver
 	GraphDriver *types.GraphDriverData `json:"GraphDriver,omitempty"`