podmanv2 events

add the ability to monitor events

Signed-off-by: Brent Baude <bbaude@redhat.com>

1 files changed, 104 insertions, 0 deletions

diff --git a/cmd/podmanV2/system/events.go b/cmd/podmanV2/system/events.go
new file mode 100644
index 000000000..9fd27e2c1
--- /dev/null
+++ b/cmd/podmanV2/system/events.go
@@ -0,0 +1,104 @@
+package system
+
+import (
+	"bufio"
+	"context"
+	"html/template"
+	"os"
+
+	"github.com/containers/buildah/pkg/formats"
+	"github.com/containers/libpod/cmd/podmanV2/registry"
+	"github.com/containers/libpod/libpod/events"
+	"github.com/containers/libpod/pkg/domain/entities"
+	"github.com/pkg/errors"
+	"github.com/spf13/cobra"
+)
+
+var (
+	eventsDescription = "Monitor podman events"
+	eventsCommand     = &cobra.Command{
+		Use:               "events",
+		Args:              cobra.NoArgs,
+		Short:             "Show podman events",
+		Long:              eventsDescription,
+		PersistentPreRunE: preRunE,
+		RunE:              eventsCmd,
+		Example: `podman events
+  podman events --filter event=create
+  podman events --since 1h30s`,
+	}
+)
+
+var (
+	eventOptions entities.EventsOptions
+	eventFormat  string
+)
+
+func init() {
+	registry.Commands = append(registry.Commands, registry.CliCommand{
+		Mode:    []entities.EngineMode{entities.ABIMode, entities.TunnelMode},
+		Command: eventsCommand,
+	})
+	flags := eventsCommand.Flags()
+	flags.StringArrayVar(&eventOptions.Filter, "filter", []string{}, "filter output")
+	flags.StringVar(&eventFormat, "format", "", "format the output using a Go template")
+	flags.BoolVar(&eventOptions.Stream, "stream", true, "stream new events; for testing only")
+	flags.StringVar(&eventOptions.Since, "since", "", "show all events created since timestamp")
+	flags.StringVar(&eventOptions.Until, "until", "", "show all events until timestamp")
+	_ = flags.MarkHidden("stream")
+}
+
+func eventsCmd(cmd *cobra.Command, args []string) error {
+	var (
+		err         error
+		eventsError error
+		tmpl        *template.Template
+	)
+	if eventFormat != formats.JSONString {
+		tmpl, err = template.New("events").Parse(eventFormat)
+		if err != nil {
+			return err
+		}
+	}
+	if len(eventOptions.Since) > 0 || len(eventOptions.Until) > 0 {
+		eventOptions.FromStart = true
+	}
+	eventChannel := make(chan *events.Event)
+	eventOptions.EventChan = eventChannel
+
+	go func() {
+		eventsError = registry.ContainerEngine().Events(context.Background(), eventOptions)
+	}()
+	if eventsError != nil {
+		return eventsError
+	}
+
+	w := bufio.NewWriter(os.Stdout)
+	for event := range eventChannel {
+		switch {
+		case eventFormat == formats.JSONString:
+			jsonStr, err := event.ToJSONString()
+			if err != nil {
+				return errors.Wrapf(err, "unable to format json")
+			}
+			if _, err := w.Write([]byte(jsonStr)); err != nil {
+				return err
+			}
+		case len(eventFormat) > 0:
+			if err := tmpl.Execute(w, event); err != nil {
+				return err
+			}
+		default:
+			if _, err := w.Write([]byte(event.ToHumanReadable())); err != nil {
+				return err
+			}
+		}
+		if _, err := w.Write([]byte("\n")); err != nil {
+			return err
+		}
+		if err := w.Flush(); err != nil {
+			return err
+		}
+	}
+	return nil
+}