add inspect command to get pid of container (#213)

feature: add inspect command to get pid of container

apis/server/container_bridge.go

@@ -176,3 +176,21 @@ func (s *Server) getContainers(ctx context.Context, resp http.ResponseWriter, re
 	resp.WriteHeader(http.StatusOK)
 	return json.NewEncoder(resp).Encode(cs)
 }
+
+func (s *Server) getContainer(ctx context.Context, resp http.ResponseWriter, req *http.Request) error {
+	name := mux.Vars(req)["name"]
+	ci, err := s.ContainerMgr.Get(name)
+	if err != nil {
+		return err
+	}
+
+	c := types.ContainerJSON{
+		ID:      ci.ID,
+		Name:    ci.Name,
+		Image:   ci.Config.Image,
+		Created: ci.StartedAt.Format("2006-01-02 15:04:05"),
+		State:   &types.ContainerState{Pid: ci.Pid},
+	}
+	resp.WriteHeader(http.StatusOK)
+	return json.NewEncoder(resp).Encode(c)
+}

apis/server/router.go

@@ -29,6 +29,7 @@ func initRoute(s *Server) http.Handler {
 	r.Path("/containers/{name:.*}/stop").Methods(http.MethodPost).Handler(s.filter(s.stopContainer))
 	r.Path("/containers/{name:.*}/attach").Methods(http.MethodPost).Handler(s.filter(s.attachContainer))
 	r.Path("/containers/json").Methods(http.MethodGet).Handler(s.filter(s.getContainers))
+	r.Path("/containers/{name:.*}/json").Methods(http.MethodGet).Handler(s.filter(s.getContainer))
 	r.Path("/containers/{name:.*}").Methods(http.MethodDelete).Handler(s.filter(s.removeContainers))
 	r.Path("/containers/{name:.*}/exec").Methods(http.MethodPost).Handler(s.filter(s.createContainerExec))
 	r.Path("/exec/{name:.*}/start").Methods(http.MethodPost).Handler(s.filter(s.startContainerExec))

apis/types/container_json.go

@@ -0,0 +1,36 @@
+package types
+
+// ContainerJSON contains response of Remote API:
+// GET "/containers/{name:.*}/json"
+type ContainerJSON struct {
+	ID              string `json:"Id"`
+	Created         string
+	Path            string
+	Args            []string
+	State           *ContainerState
+	Image           string
+	ResolvConfPath  string
+	HostnamePath    string
+	HostsPath       string
+	LogPath         string
+	Name            string
+	RestartCount    int
+	Driver          string
+	MountLabel      string
+	ProcessLabel    string
+	AppArmorProfile string
+	ExecIDs         []string
+	HostConfig      *HostConfig
+	SizeRw          *int64 `json:",omitempty"`
+	SizeRootFs      *int64 `json:",omitempty"`
+	HostRootPath    string
+}
+
+// TODO
+// ContainerJSON is newly used struct along with MountPoint
+//type ContainerJSON struct {
+//	*ContainerJSONBase
+//	Mounts          []MountPoint
+//	Config          *container.Config
+//	NetworkSettings *NetworkSettings
+//}

cli/inspect.go

@@ -0,0 +1,81 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+
+	"github.com/spf13/cobra"
+)
+
+// inspectDescription is used to describe inspect command in detail and auto generate command doc.
+var inspectDescription = "Return detailed information on Pouch container"
+
+// InspectCommand is used to implement 'inspect' command.
+type InspectCommand struct {
+	baseCommand
+}
+
+// Init initializes InspectCommand command.
+func (p *InspectCommand) Init(c *Cli) {
+	p.cli = c
+	p.cmd = &cobra.Command{
+		Use:   "inspect [container]",
+		Short: "Get the detailed information of container",
+		Long:  inspectDescription,
+		Args:  cobra.ExactArgs(1),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return p.runInpsect(args)
+		},
+		Example: inspectExample(),
+	}
+}
+
+// runInpsect is the entry of InspectCommand command.
+func (p *InspectCommand) runInpsect(args []string) error {
+	apiClient := p.cli.Client()
+	name := args[0]
+	container, err := apiClient.ContainerGet(name)
+	if err != nil {
+		return err
+	}
+
+	containerjson, err := json.MarshalIndent(&container, "", "  ")
+	if err != nil {
+		return err
+	}
+	fmt.Print(string(containerjson) + "\n")
+	return nil
+}
+
+// inspectExample shows examples in inspect command, and is used in auto-generated cli docs.
+func inspectExample() string {
+	return `$ pouch inspect 08e
+{
+  "Id": "08ee444faa3c6634ecdecea26de46e8a6a16efefd9afb72eb3457320b333fc60",
+  "Created": "2017-12-04 14:48:59",
+  "Path": "",
+  "Args": null,
+  "State": {
+    "StartedAt": "0001-01-01T00:00:00Z",
+    "Status": 0,
+    "FinishedAt": "0001-01-01T00:00:00Z",
+    "Pid": 25006,
+    "ExitCode": 0,
+    "Error": ""
+  },
+  "Image": "registry.docker-cn.com/library/centos:latest",
+  "ResolvConfPath": "",
+  "HostnamePath": "",
+  "HostsPath": "",
+  "LogPath": "",
+  "Name": "08ee44",
+  "RestartCount": 0,
+  "Driver": "",
+  "MountLabel": "",
+  "ProcessLabel": "",
+  "AppArmorProfile": "",
+  "ExecIDs": null,
+  "HostConfig": null,
+  "HostRootPath": ""
+}`
+}

cli/main.go

@@ -23,6 +23,7 @@ func main() {
 	cli.AddCommand(base, &VersionCommand{})
 	cli.AddCommand(base, &ImageCommand{})
 	cli.AddCommand(base, &VolumeCommand{})
+	cli.AddCommand(base, &InspectCommand{})
 
 	// add generate doc command
 	cli.AddCommand(base, &GenDocCommand{})

client/container.go

@@ -106,3 +106,17 @@ func (client *APIClient) ContainerStartExec(execid string, config *types.ExecSta
 
 	return client.hijack("/exec/"+execid+"/start", url.Values{}, config, header)
 }
+
+// ContainerGet returns the detailed information of container.
+func (client *APIClient) ContainerGet(name string) (*types.ContainerJSON, error) {
+	resp, err := client.get("/containers/"+name+"/json", nil)
+	if err != nil {
+		return nil, err
+	}
+
+	container := types.ContainerJSON{}
+	err = decodeBody(&container, resp.Body)
+	ensureCloseReader(resp)
+
+	return &container, err
+}

daemon/mgr/container.go

@@ -48,6 +48,9 @@ type ContainerMgr interface {
 
 	// Remove removes a container, it may be running or stopped and so on.
 	Remove(ctx context.Context, name string, option *ContainerRemoveOption) error
+
+	// Get the detailed information of container
+	Get(s string) (*types.ContainerInfo, error)
 }
 
 // ContainerManager is the default implement of interface ContainerMgr.
@@ -285,7 +288,11 @@ func (cm *ContainerManager) Start(ctx context.Context, cfg types.ContainerStartC
 	if err == nil {
 		c.Status = types.RUNNING
 		c.StartedAt = time.Now()
-		//TODO get and set container pid
+		pid, err := cm.Client.ContainerPID(ctx, c.ID)
+		if err != nil {
+			return errors.Wrapf(err, "failed to get PID of container: %s", c.ID)
+		}
+		c.Pid = pid
 	} else {
 		c.FinishedAt = time.Now()
 		c.ErrorMsg = err.Error()
@@ -364,6 +371,11 @@ func (cm *ContainerManager) List(ctx context.Context) ([]*types.ContainerInfo, e
 	return cis, nil
 }
 
+// Get the detailed information of container
+func (cm *ContainerManager) Get(s string) (*types.ContainerInfo, error) {
+	return cm.containerInfo(s)
+}
+
 // containerInfo returns the 'ContainerInfo' object, the parameter 's' may be container's
 // name, id or prefix id.
 func (cm *ContainerManager) containerInfo(s string) (*types.ContainerInfo, error) {