Add podman pod top

Using the vendored changes from psgo, incorporate JoinNamespaceAndProcessInfoByPids to get process information for each pid namespace of running containers in the pod. Also added a man page, and tests.

Signed-off-by: haircommander <pehunt@redhat.com>

Closes: #1298
Approved by: mheon

7 files changed, 402 insertions, 1 deletions

diff --git a/cmd/podman/pod.go b/cmd/podman/pod.go
index e691204d8..dde43f77c 100644
--- a/cmd/podman/pod.go
+++ b/cmd/podman/pod.go
@@ -20,6 +20,7 @@ Pods are a group of one or more containers sharing the same network, pid and ipc
 		podStartCommand,
 		podStatsCommand,
 		podStopCommand,
+		podTopCommand,
 		podUnpauseCommand,
 	}
 	podCommand = cli.Command{
diff --git a/cmd/podman/pod_top.go b/cmd/podman/pod_top.go
new file mode 100644
index 000000000..703ec0a44
--- /dev/null
+++ b/cmd/podman/pod_top.go
@@ -0,0 +1,101 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"strings"
+	"text/tabwriter"
+
+	"github.com/containers/libpod/cmd/podman/libpodruntime"
+	"github.com/containers/libpod/cmd/podman/shared"
+	"github.com/containers/libpod/libpod"
+	"github.com/pkg/errors"
+	"github.com/urfave/cli"
+)
+
+var (
+	podTopFlags = []cli.Flag{
+		LatestFlag,
+		cli.BoolFlag{
+			Name:   "list-descriptors",
+			Hidden: true,
+		},
+	}
+	podTopDescription = fmt.Sprintf(`Display the running processes containers in a pod.  Specify format descriptors
+to alter the output.  You may run "podman pod top -l pid pcpu seccomp" to print
+the process ID, the CPU percentage and the seccomp mode of each process of
+the latest pod.
+%s
+`, getDescriptorString())
+
+	podTopCommand = cli.Command{
+		Name:           "top",
+		Usage:          "Display the running processes of containers in a pod",
+		Description:    podTopDescription,
+		Flags:          podTopFlags,
+		Action:         podTopCmd,
+		ArgsUsage:      "POD-NAME [format descriptors]",
+		SkipArgReorder: true,
+	}
+)
+
+func podTopCmd(c *cli.Context) error {
+	var pod *libpod.Pod
+	var err error
+	args := c.Args()
+
+	if c.Bool("list-descriptors") {
+		descriptors, err := libpod.GetContainerPidInformationDescriptors()
+		if err != nil {
+			return err
+		}
+		fmt.Println(strings.Join(descriptors, "\n"))
+		return nil
+	}
+
+	if len(args) < 1 && !c.Bool("latest") {
+		return errors.Errorf("you must provide the name or id of a running pod")
+	}
+	if err := validateFlags(c, podTopFlags); err != nil {
+		return err
+	}
+
+	runtime, err := libpodruntime.GetRuntime(c)
+	if err != nil {
+		return errors.Wrapf(err, "error creating libpod runtime")
+	}
+	defer runtime.Shutdown(false)
+
+	var descriptors []string
+	if c.Bool("latest") {
+		descriptors = args
+		pod, err = runtime.GetLatestPod()
+	} else {
+		descriptors = args[1:]
+		pod, err = runtime.LookupPod(args[0])
+	}
+
+	if err != nil {
+		return errors.Wrapf(err, "unable to lookup requested container")
+	}
+
+	podStatus, err := shared.GetPodStatus(pod)
+	if err != nil {
+		return err
+	}
+	if podStatus != "Running" {
+		return errors.Errorf("pod top can only be used on pods with at least one running container")
+	}
+
+	psOutput, err := pod.GetPodPidInformation(descriptors)
+	if err != nil {
+		return err
+	}
+
+	w := tabwriter.NewWriter(os.Stdout, 5, 1, 3, ' ', 0)
+	for _, proc := range psOutput {
+		fmt.Fprintln(w, proc)
+	}
+	w.Flush()
+	return nil
+}
diff --git a/docs/podman-pod-top.1.md b/docs/podman-pod-top.1.md
new file mode 100644
index 000000000..7a66b4534
--- /dev/null
+++ b/docs/podman-pod-top.1.md
@@ -0,0 +1,92 @@
+% podman-pod-top "1"
+
+## NAME
+podman\-pod\-top - Display the running processes of containers in a pod
+
+## SYNOPSIS
+**podman top** [*options*] *pod* [*format-descriptors*]
+
+## DESCRIPTION
+Display the running process of containers in a pod. The *format-descriptors* are ps (1) compatible AIX format descriptors but extended to print additional information, such as the seccomp mode or the effective capabilities of a given process.
+
+## OPTIONS
+
+**--help, -h**
+
+  Print usage statement
+
+**--latest, -l**
+
+Instead of providing the pod name or ID, use the last created pod.
+
+## FORMAT DESCRIPTORS
+
+The following descriptors are supported in addition to the AIX format descriptors mentioned in ps (1):
+
+**args, capbnd, capeff, capinh, capprm, comm, etime, group, hgroup, hpid, huser, label, nice, pcpu, pgid, pid, ppid, rgroup, ruser, seccomp, state, time, tty, user, vsz**
+
+**capbnd**
+
+  Set of bounding capabilities. See capabilities (7) for more information.
+
+**capeff**
+
+  Set of effective capabilities. See capabilities (7) for more information.
+
+**capinh**
+
+  Set of inheritable capabilities. See capabilities (7) for more information.
+
+**capprm**
+
+  Set of permitted capabilities. See capabilities (7) for more information.
+
+**hgroup**
+
+  The corresponding effective group of a container process on the host.
+
+**hpid**
+
+  The corresponding host PID of a container process.
+
+**huser**
+
+  The corresponding effective user of a container process on the host.
+
+**label**
+
+  Current security attributes of the process.
+
+**seccomp**
+
+  Seccomp mode of the process (i.e., disabled, strict or filter). See seccomp (2) for more information.
+
+**state**
+
+  Process state codes (e.g, **R** for *running*, **S** for *sleeping*). See proc(5) for more information.
+
+## EXAMPLES
+
+By default, `podman-top` prints data similar to `ps -ef`:
+
+```
+ # podman pod top b031293491cc
+USER   PID   PPID   %CPU    ELAPSED             TTY   TIME   COMMAND
+root   1     0      0.000   2h5m38.737137571s   ?     0s     top
+root   8     0      0.000   2h5m15.737228361s   ?     0s     top
+```
+
+The output can be controlled by specifying format descriptors as arguments after the pod:
+
+```
+ # podman pod top -l pid seccomp args %C
+PID   SECCOMP   COMMAND   %CPU
+1     filter    top       0.000
+1     filter    /bin/sh   0.000
+```
+
+## SEE ALSO
+podman-pod(1), ps(1), seccomp(2), proc(5), capabilities(7)
+
+## HISTORY
+August 2018, Originally compiled by Peter Hunt <pehunt@redhat.com>
diff --git a/libpod/pod_top_linux.go b/libpod/pod_top_linux.go
new file mode 100644
index 000000000..f49e28c9d
--- /dev/null
+++ b/libpod/pod_top_linux.go
@@ -0,0 +1,55 @@
+// +build linux
+
+package libpod
+
+import (
+	"strconv"
+	"strings"
+
+	"github.com/containers/psgo"
+)
+
+// GetPodPidInformation returns process-related data of all processes in
+// the pod.  The output data can be controlled via the `descriptors`
+// argument which expects format descriptors and supports all AIXformat
+// descriptors of ps (1) plus some additional ones to for instance inspect the
+// set of effective capabilities.  Eeach element in the returned string slice
+// is a tab-separated string.
+//
+// For more details, please refer to github.com/containers/psgo.
+func (p *Pod) GetPodPidInformation(descriptors []string) ([]string, error) {
+	p.lock.Lock()
+	defer p.lock.Unlock()
+
+	pids := make([]string, 0)
+	ctrsInPod, err := p.allContainers()
+	if err != nil {
+		return nil, err
+	}
+	for _, c := range ctrsInPod {
+		c.lock.Lock()
+
+		if err := c.syncContainer(); err != nil {
+			c.lock.Unlock()
+			return nil, err
+		}
+		if c.state.State == ContainerStateRunning {
+			pid := strconv.Itoa(c.state.PID)
+			pids = append(pids, pid)
+		}
+		c.lock.Unlock()
+	}
+	// TODO: psgo returns a [][]string to give users the ability to apply
+	//       filters on the data.  We need to change the API here and the
+	//       varlink API to return a [][]string if we want to make use of
+	//       filtering.
+	output, err := psgo.JoinNamespaceAndProcessInfoByPids(pids, descriptors)
+	if err != nil {
+		return nil, err
+	}
+	res := []string{}
+	for _, out := range output {
+		res = append(res, strings.Join(out, "\t"))
+	}
+	return res, nil
+}
diff --git a/libpod/pod_top_unsupported.go b/libpod/pod_top_unsupported.go
new file mode 100644
index 000000000..d44470523
--- /dev/null
+++ b/libpod/pod_top_unsupported.go
@@ -0,0 +1,8 @@
+// +build !linux
+
+package libpod
+
+// GetPodPidInformation is exclusive to linux
+func (p *Pod) GetPodPidInformation(descriptors []string) ([]string, error) {
+	return nil, ErrNotImplemented
+}
diff --git a/test/e2e/pod_top_test.go b/test/e2e/pod_top_test.go
new file mode 100644
index 000000000..2b4aa540f
--- /dev/null
+++ b/test/e2e/pod_top_test.go
@@ -0,0 +1,144 @@
+package integration
+
+import (
+	"fmt"
+	"os"
+
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("Podman top", func() {
+	var (
+		tempdir    string
+		err        error
+		podmanTest PodmanTest
+	)
+
+	BeforeEach(func() {
+		tempdir, err = CreateTempDirInTempDir()
+		if err != nil {
+			os.Exit(1)
+		}
+		podmanTest = PodmanCreate(tempdir)
+		podmanTest.RestoreAllArtifacts()
+	})
+
+	AfterEach(func() {
+		podmanTest.CleanupPod()
+		f := CurrentGinkgoTestDescription()
+		timedResult := fmt.Sprintf("Test: %s completed in %f seconds", f.TestText, f.Duration.Seconds())
+		GinkgoWriter.Write([]byte(timedResult))
+	})
+
+	It("podman pod top without pod name or id", func() {
+		result := podmanTest.Podman([]string{"pod", "top"})
+		result.WaitWithDefaultTimeout()
+		Expect(result.ExitCode()).To(Equal(125))
+	})
+
+	It("podman pod top on bogus pod", func() {
+		result := podmanTest.Podman([]string{"pod", "top", "1234"})
+		result.WaitWithDefaultTimeout()
+		Expect(result.ExitCode()).To(Equal(125))
+	})
+
+	It("podman pod top on non-running pod", func() {
+		session := podmanTest.Podman([]string{"pod", "create"})
+		session.WaitWithDefaultTimeout()
+		Expect(session.ExitCode()).To(Equal(0))
+		podid := session.OutputToString()
+
+		result := podmanTest.Podman([]string{"top", podid})
+		result.WaitWithDefaultTimeout()
+		Expect(result.ExitCode()).To(Equal(125))
+	})
+
+	It("podman pod top on pod", func() {
+		session := podmanTest.Podman([]string{"pod", "create"})
+		session.WaitWithDefaultTimeout()
+		Expect(session.ExitCode()).To(Equal(0))
+		podid := session.OutputToString()
+
+		session = podmanTest.Podman([]string{"run", "-d", "--pod", podid, ALPINE, "top", "-d", "2"})
+		session.WaitWithDefaultTimeout()
+		Expect(session.ExitCode()).To(Equal(0))
+
+		result := podmanTest.Podman([]string{"pod", "top", "-l"})
+		result.WaitWithDefaultTimeout()
+		Expect(result.ExitCode()).To(Equal(0))
+		Expect(len(result.OutputToStringArray())).To(BeNumerically(">", 1))
+	})
+
+	It("podman pod top with options", func() {
+		session := podmanTest.Podman([]string{"pod", "create"})
+		session.WaitWithDefaultTimeout()
+		Expect(session.ExitCode()).To(Equal(0))
+		podid := session.OutputToString()
+
+		session = podmanTest.Podman([]string{"run", "-d", "--pod", podid, ALPINE, "top", "-d", "2"})
+		session.WaitWithDefaultTimeout()
+		Expect(session.ExitCode()).To(Equal(0))
+
+		result := podmanTest.Podman([]string{"pod", "top", podid, "pid", "%C", "args"})
+		result.WaitWithDefaultTimeout()
+		Expect(result.ExitCode()).To(Equal(0))
+		Expect(len(result.OutputToStringArray())).To(BeNumerically(">", 1))
+	})
+
+	It("podman pod top on pod invalid options", func() {
+		session := podmanTest.Podman([]string{"pod", "create"})
+		session.WaitWithDefaultTimeout()
+		Expect(session.ExitCode()).To(Equal(0))
+		podid := session.OutputToString()
+
+		session = podmanTest.Podman([]string{"run", "-d", "--pod", podid, ALPINE, "top", "-d", "2"})
+		session.WaitWithDefaultTimeout()
+		Expect(session.ExitCode()).To(Equal(0))
+
+		result := podmanTest.Podman([]string{"pod", "top", podid, "invalid"})
+		result.WaitWithDefaultTimeout()
+		Expect(result.ExitCode()).To(Equal(125))
+	})
+
+	It("podman pod top on pod with containers in same pid namespace", func() {
+		session := podmanTest.Podman([]string{"pod", "create"})
+		session.WaitWithDefaultTimeout()
+		Expect(session.ExitCode()).To(Equal(0))
+		podid := session.OutputToString()
+
+		session = podmanTest.Podman([]string{"run", "-d", "--pod", podid, ALPINE, "top", "-d", "2"})
+		session.WaitWithDefaultTimeout()
+		Expect(session.ExitCode()).To(Equal(0))
+		cid := session.OutputToString()
+
+		session = podmanTest.Podman([]string{"run", "-d", "--pod", podid, "--pid", fmt.Sprintf("container:%s", cid), ALPINE, "top", "-d", "2"})
+		session.WaitWithDefaultTimeout()
+		Expect(session.ExitCode()).To(Equal(0))
+
+		result := podmanTest.Podman([]string{"pod", "top", podid})
+		result.WaitWithDefaultTimeout()
+		Expect(result.ExitCode()).To(Equal(0))
+		Expect(len(result.OutputToStringArray())).To(Equal(4))
+	})
+
+	It("podman pod top on pod with containers in different namespace", func() {
+		session := podmanTest.Podman([]string{"pod", "create"})
+		session.WaitWithDefaultTimeout()
+		Expect(session.ExitCode()).To(Equal(0))
+		podid := session.OutputToString()
+
+		session = podmanTest.Podman([]string{"run", "-d", "--pod", podid, ALPINE, "top", "-d", "2"})
+		session.WaitWithDefaultTimeout()
+		Expect(session.ExitCode()).To(Equal(0))
+
+		session = podmanTest.Podman([]string{"run", "-d", "--pod", podid, ALPINE, "top", "-d", "2"})
+		session.WaitWithDefaultTimeout()
+		Expect(session.ExitCode()).To(Equal(0))
+
+		result := podmanTest.Podman([]string{"pod", "top", podid})
+		result.WaitWithDefaultTimeout()
+		Expect(result.ExitCode()).To(Equal(0))
+		Expect(len(result.OutputToStringArray())).To(Equal(4))
+	})
+})
diff --git a/vendor.conf b/vendor.conf
index 86278ae05..4a2e82e7a 100644
--- a/vendor.conf
+++ b/vendor.conf
@@ -12,7 +12,7 @@ github.com/containernetworking/cni v0.7.0-alpha1
 github.com/containernetworking/plugins 1562a1e60ed101aacc5e08ed9dbeba8e9f3d4ec1
 github.com/containers/image 134f99bed228d6297dc01d152804f6f09f185418
 github.com/containers/storage 17c7d1fee5603ccf6dd97edc14162fc1510e7e23
-github.com/containers/psgo master
+github.com/containers/psgo 5dde6da0bc8831b35243a847625bcf18183bd1ee
 github.com/coreos/go-systemd v14
 github.com/cri-o/ocicni master
 github.com/cyphar/filepath-securejoin v0.2.1