Allow duration strings as --since/--until

Fixes #13107. This change enables Go duration strings
computed relative to the client machine’s time to be used
as input parameters to `docker events --since/--until`
and `docker logs --since` arguments.

Added unit tests for pkg/timeutils.GetTimestamp as well.

Signed-off-by: Ahmet Alp Balkan <ahmetalpbalkan@gmail.com>

timeutils/utils.go

@@ -6,10 +6,17 @@ import (
 	"time"
 )
 
-// GetTimestamp tries to parse given string as RFC3339 time
+// GetTimestamp tries to parse given string as golang duration,
-// or Unix timestamp (with seconds precision), if successful
+// then RFC3339 time and finally as a Unix timestamp. If
-//returns a Unix timestamp as string otherwise returns value back.
+// any of these were successful, it returns a Unix timestamp
-func GetTimestamp(value string) string {
+// as string otherwise returns the given value back.
+// In case of duration input, the returned timestamp is computed
+// as the given reference time minus the amount of the duration.
+func GetTimestamp(value string, reference time.Time) string {
+	if d, err := time.ParseDuration(value); value != "0" && err == nil {
+		return strconv.FormatInt(reference.Add(-d).Unix(), 10)
+	}
+
 	var format string
 	if strings.Contains(value, ".") {
 		format = time.RFC3339Nano

timeutils/utils_test.go

@@ -1,10 +1,13 @@
 package timeutils
 
 import (
+	"fmt"
 	"testing"
+	"time"
 )
 
 func TestGetTimestamp(t *testing.T) {
+	now := time.Now()
 	cases := []struct{ in, expected string }{
 		{"0", "-62167305600"}, // 0 gets parsed year 0
 
@@ -23,12 +26,17 @@ func TestGetTimestamp(t *testing.T) {
 		// unix timestamps returned as is
 		{"1136073600", "1136073600"},
 
+		// Durations
+		{"1m", fmt.Sprintf("%d", now.Add(-1*time.Minute).Unix())},
+		{"1.5h", fmt.Sprintf("%d", now.Add(-90*time.Minute).Unix())},
+		{"1h30m", fmt.Sprintf("%d", now.Add(-90*time.Minute).Unix())},
+
 		// String fallback
 		{"invalid", "invalid"},
 	}
 
 	for _, c := range cases {
-		o := GetTimestamp(c.in)
+		o := GetTimestamp(c.in, now)
 		if o != c.expected {
 			t.Fatalf("wrong value for '%s'. expected:'%s' got:'%s'", c.in, c.expected, o)
 		}