get last container event

an internal change in libpod will soon required the ability to lookup
the last container event using the continer name or id and the type of
event.  this pr is in preperation for that need.

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

1 files changed, 55 insertions, 0 deletions

diff --git a/libpod/events.go b/libpod/events.go
index 13bb5bdde..be21e510a 100644
--- a/libpod/events.go
+++ b/libpod/events.go
@@ -1,7 +1,10 @@
 package libpod
 
 import (
+	"fmt"
+
 	"github.com/containers/libpod/libpod/events"
+	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 )
 
@@ -79,3 +82,55 @@ func (r *Runtime) Events(options events.ReadOptions) error {
 	}
 	return eventer.Read(options)
 }
+
+// GetEvents reads the event log and returns events based on input filters
+func (r *Runtime) GetEvents(filters []string) ([]*events.Event, error) {
+	var (
+		logEvents []*events.Event
+		readErr   error
+	)
+	eventChannel := make(chan *events.Event)
+	options := events.ReadOptions{
+		EventChannel: eventChannel,
+		Filters:      filters,
+		FromStart:    true,
+		Stream:       false,
+	}
+	eventer, err := r.newEventer()
+	if err != nil {
+		return nil, err
+	}
+	go func() {
+		readErr = eventer.Read(options)
+	}()
+	if readErr != nil {
+		return nil, readErr
+	}
+	for e := range eventChannel {
+		logEvents = append(logEvents, e)
+	}
+	return logEvents, nil
+}
+
+// GetLastContainerEvent takes a container name or ID and an event status and returns
+// the last occurrence of the container event
+func (r *Runtime) GetLastContainerEvent(nameOrID string, containerEvent events.Status) (*events.Event, error) {
+	// check to make sure the event.Status is valid
+	if _, err := events.StringToStatus(containerEvent.String()); err != nil {
+		return nil, err
+	}
+	filters := []string{
+		fmt.Sprintf("container=%s", nameOrID),
+		fmt.Sprintf("event=%s", containerEvent),
+		"type=container",
+	}
+	containerEvents, err := r.GetEvents(filters)
+	if err != nil {
+		return nil, err
+	}
+	if len(containerEvents) < 1 {
+		return nil, errors.Wrapf(events.ErrEventNotFound, "%s not found", containerEvent.String())
+	}
+	// return the last element in the slice
+	return containerEvents[len(containerEvents)-1], nil
+}