Support label filters for podman pod ps.

Update the podman pod ps command to support filtering by labels.
This brings the command in line with the documentation as well as
the functionality by the containers equivalent podman ps.

Signed-off-by: Stefano Pogliani <stefano@spogliani.net>

cmd/podman/shared/pod.go

@@ -162,7 +162,7 @@ func FilterAllPodsWithFilterFunc(r *libpod.Runtime, filters ...libpod.PodFilter)
 func GenerateFilterFunction(r *libpod.Runtime, filters []string) ([]libpod.PodFilter, error) {
 	var filterFuncs []libpod.PodFilter
 	for _, f := range filters {
-		filterSplit := strings.Split(f, "=")
+		filterSplit := strings.SplitN(f, "=", 2)
 		if len(filterSplit) < 2 {
 			return nil, errors.Errorf("filter input must be in the form of filter=value: %s is invalid", f)
 		}
@@ -256,6 +256,22 @@ func generatePodFilterFuncs(filter, filterValue string) (
 			}
 			return false
 		}, nil
+	case "label":
+		var filterArray = strings.SplitN(filterValue, "=", 2)
+		var filterKey = filterArray[0]
+		if len(filterArray) > 1 {
+			filterValue = filterArray[1]
+		} else {
+			filterValue = ""
+		}
+		return func(p *libpod.Pod) bool {
+			for labelKey, labelValue := range p.Labels() {
+				if labelKey == filterKey && ("" == filterValue || labelValue == filterValue) {
+					return true
+				}
+			}
+			return false
+		}, nil
 	}
 	return nil, errors.Errorf("%s is an invalid filter", filter)
 }

test/e2e/common_test.go

@@ -519,6 +519,21 @@ func (p *PodmanTestIntegration) CreatePod(name string) (*PodmanSessionIntegratio
 	return session, session.ExitCode(), session.OutputToString()
 }
 
+// CreatePod creates a pod with no infra container and some labels.
+// it optionally takes a pod name
+func (p *PodmanTestIntegration) CreatePodWithLabels(name string, labels map[string]string) (*PodmanSessionIntegration, int, string) {
+	var podmanArgs = []string{"pod", "create", "--infra=false", "--share", ""}
+	if name != "" {
+		podmanArgs = append(podmanArgs, "--name", name)
+	}
+	for labelKey, labelValue := range labels {
+		podmanArgs = append(podmanArgs, "--label", fmt.Sprintf("%s=%s", labelKey, labelValue))
+	}
+	session := p.Podman(podmanArgs)
+	session.WaitWithDefaultTimeout()
+	return session, session.ExitCode(), session.OutputToString()
+}
+
 func (p *PodmanTestIntegration) RunTopContainerInPod(name, pod string) *PodmanSessionIntegration {
 	var podmanArgs = []string{"run", "--pod", pod}
 	if name != "" {

test/e2e/pod_ps_test.go

@@ -204,4 +204,27 @@ var _ = Describe("Podman ps", func() {
 		Expect(session.ExitCode()).To(Equal(0))
 		Expect(session.OutputToString()).To(BeEmpty())
 	})
+
+	It("podman pod ps filter labels", func() {
+		_, ec, podid1 := podmanTest.CreatePod("")
+		Expect(ec).To(Equal(0))
+
+		_, ec, podid2 := podmanTest.CreatePodWithLabels("", map[string]string{
+			"io.podman.test.label": "value1",
+			"io.podman.test.key":   "irrelevant-value",
+		})
+		Expect(ec).To(Equal(0))
+
+		_, ec, podid3 := podmanTest.CreatePodWithLabels("", map[string]string{
+			"io.podman.test.label": "value2",
+		})
+		Expect(ec).To(Equal(0))
+
+		session := podmanTest.Podman([]string{"pod", "ps", "--no-trunc", "--filter", "label=io.podman.test.key", "--filter", "label=io.podman.test.label=value1"})
+		session.WaitWithDefaultTimeout()
+		Expect(session.ExitCode()).To(Equal(0))
+		Expect(session.OutputToString()).To(Not(ContainSubstring(podid1)))
+		Expect(session.OutputToString()).To(ContainSubstring(podid2))
+		Expect(session.OutputToString()).To(Not(ContainSubstring(podid3)))
+	})
 })