[docker]linux: add CgroupDockerStat (shirou#189)

docker/docker.go

@@ -39,3 +39,11 @@ type CgroupMemStat struct {
 	MemLimitInBytes         uint64 `json:"memoryLimitInBbytes"`
 	MemFailCnt              uint64 `json:"memoryFailcnt"`
 }
+
+type CgroupDockerStat struct {
+	ContainerID string `json:"containerID"`
+	Name        string `json:"name"`
+	Image       string `json:"image"`
+	Status      string `json:"status"`
+	Running     bool   `json:"running"`
+}

docker/docker_linux.go

@@ -15,6 +15,48 @@ import (
 	"github.com/shirou/gopsutil/internal/common"
 )
 
+// GetDockerStat returns a list of Docker basic stats.
+// This requires certain permission.
+func GetDockerStat() ([]CgroupDockerStat, error) {
+	path, err := exec.LookPath("docker")
+	if err != nil {
+		return nil, ErrDockerNotAvailable
+	}
+
+	out, err := exec.Command(path, "ps", "-a", "--no-trunc", "--format", "{{.ID}}|{{.Image}}|{{.Names}}|{{.Status}}").Output()
+	if err != nil {
+		return []CgroupDockerStat{}, err
+	}
+	lines := strings.Split(string(out), "\n")
+	ret := make([]CgroupDockerStat, 0, len(lines))
+
+	for _, l := range lines {
+		if l == "" {
+			continue
+		}
+		cols := strings.Split(l, "|")
+		if len(cols) != 4 {
+			continue
+		}
+		names := strings.Split(cols[2], ",")
+		stat := CgroupDockerStat{
+			ContainerID: cols[0],
+			Name:        names[0],
+			Image:       cols[1],
+			Status:      cols[3],
+			Running:     strings.Contains(cols[3], "Up"),
+		}
+		ret = append(ret, stat)
+	}
+
+	return ret, nil
+}
+
+func (c CgroupDockerStat) String() string {
+	s, _ := json.Marshal(c)
+	return string(s)
+}
+
 // GetDockerIDList returnes a list of DockerID.
 // This requires certain permission.
 func GetDockerIDList() ([]string, error) {

docker/docker_linux_test.go

@@ -15,6 +15,30 @@ func TestGetDockerIDList(t *testing.T) {
 	*/
 }
 
+func TestGetDockerStat(t *testing.T) {
+	// If there is not docker environment, this test always fail.
+	// not tested here
+
+	/*
+		ret, err := GetDockerStat()
+		if err != nil {
+			t.Errorf("error %v", err)
+		}
+		if len(ret) == 0 {
+			t.Errorf("ret is empty")
+		}
+		empty := CgroupDockerStat{}
+		for _, v := range ret {
+			if empty == v {
+				t.Errorf("empty CgroupDockerStat")
+			}
+			if v.ContainerID == "" {
+				t.Errorf("Could not get container id")
+			}
+		}
+	*/
+}
+
 func TestCgroupCPU(t *testing.T) {
 	v, _ := GetDockerIDList()
 	for _, id := range v {

docker/docker_notlinux.go

@@ -9,6 +9,12 @@ import (
 	"github.com/shirou/gopsutil/internal/common"
 )
 
+// GetDockerStat returns a list of Docker basic stats.
+// This requires certain permission.
+func GetDockerStat() ([]CgroupDockerStat, error) {
+	return nil, ErrDockerNotAvailable
+}
+
 // GetDockerIDList returnes a list of DockerID.
 // This requires certain permission.
 func GetDockerIDList() ([]string, error) {