moby/daemon/top_unix.go
David Calavera ca5ede2d0a Decouple daemon and container to log events.
Create a supervisor interface to let the container monitor to emit events.

Signed-off-by: David Calavera <david.calavera@gmail.com>
2015-11-04 12:27:48 -05:00

81 lines
2 KiB
Go

//+build !windows
package daemon
import (
"os/exec"
"strconv"
"strings"
"github.com/docker/docker/api/types"
derr "github.com/docker/docker/errors"
)
// ContainerTop lists the processes running inside of the given
// container by calling ps with the given args, or with the flags
// "-ef" if no args are given. An error is returned if the container
// is not found, or is not running, or if there are any problems
// running ps, or parsing the output.
func (daemon *Daemon) ContainerTop(name string, psArgs string) (*types.ContainerProcessList, error) {
if psArgs == "" {
psArgs = "-ef"
}
container, err := daemon.Get(name)
if err != nil {
return nil, err
}
if !container.IsRunning() {
return nil, derr.ErrorCodeNotRunning.WithArgs(name)
}
pids, err := daemon.ExecutionDriver().GetPidsForContainer(container.ID)
if err != nil {
return nil, err
}
output, err := exec.Command("ps", strings.Split(psArgs, " ")...).Output()
if err != nil {
return nil, derr.ErrorCodePSError.WithArgs(err)
}
procList := &types.ContainerProcessList{}
lines := strings.Split(string(output), "\n")
procList.Titles = strings.Fields(lines[0])
pidIndex := -1
for i, name := range procList.Titles {
if name == "PID" {
pidIndex = i
}
}
if pidIndex == -1 {
return nil, derr.ErrorCodeNoPID
}
// loop through the output and extract the PID from each line
for _, line := range lines[1:] {
if len(line) == 0 {
continue
}
fields := strings.Fields(line)
p, err := strconv.Atoi(fields[pidIndex])
if err != nil {
return nil, derr.ErrorCodeBadPID.WithArgs(fields[pidIndex], err)
}
for _, pid := range pids {
if pid == p {
// Make sure number of fields equals number of header titles
// merging "overhanging" fields
process := fields[:len(procList.Titles)-1]
process = append(process, strings.Join(fields[len(procList.Titles)-1:], " "))
procList.Processes = append(procList.Processes, process)
}
}
}
daemon.LogContainerEvent(container, "top")
return procList, nil
}