Core: use go-datemath in timerange utility (#23120)

* Core: use go-datemath in time_range

* Core: update timerange for negative epoch

* Core: update gtime component

* Core: clean up time_range tests

* Update pkg/components/gtime/gtime.go

Co-Authored-By: Arve Knudsen <arve.knudsen@gmail.com>

* Core: clean gtime tests

* components/gtime: Fix test

Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com>

Co-authored-by: Arve Knudsen <arve.knudsen@gmail.com>

pkg/components/gtime/gtime.go

 package gtime
 
 import (
+	"fmt"
 	"regexp"
 	"strconv"
 	"time"
 )
 
-var dateUnitPattern = regexp.MustCompile(`(\d+)([wdy])`)
+var dateUnitPattern = regexp.MustCompile(`^(\d+)([dwMy])$`)
 
 // ParseInterval parses an interval with support for all units that Grafana uses.
 func ParseInterval(interval string) (time.Duration, error) {
@@ -18,14 +19,18 @@ func ParseInterval(interval string) (time.Duration, error) {
 
 	num, _ := strconv.Atoi(string(result[1]))
 	period := string(result[2])
-
-	if period == `d` {
-		return time.Hour * 24 * time.Duration(num), nil
-	}
-
-	if period == `w` {
-		return time.Hour * 24 * 7 * time.Duration(num), nil
+	now := time.Now()
+
+	switch period {
+	case "d":
+		return now.Sub(now.AddDate(0, 0, -num)), nil
+	case "w":
+		return now.Sub(now.AddDate(0, 0, -num*7)), nil
+	case "M":
+		return now.Sub(now.AddDate(0, -num, 0)), nil
+	case "y":
+		return now.Sub(now.AddDate(-num, 0, 0)), nil
 	}
 
-	return time.Hour * 24 * 7 * 365 * time.Duration(num), nil
+	return 0, fmt.Errorf("ParseInterval: invalid duration %q", interval)
 }

pkg/components/gtime/gtime_test.go

 package gtime
 
 import (
-	"errors"
 	"fmt"
 	"testing"
 	"time"
+
+	"github.com/stretchr/testify/require"
 )
 
 func TestParseInterval(t *testing.T) {
+	now := time.Now()
+
 	tcs := []struct {
 		interval string
 		duration time.Duration
-		err      error
+		err      string
 	}{
-		{interval: "1d", duration: time.Hour * 24},
-		{interval: "1w", duration: time.Hour * 24 * 7},
-		{interval: "2w", duration: time.Hour * 24 * 7 * 2},
-		{interval: "1y", duration: time.Hour * 24 * 7 * 365},
-		{interval: "5y", duration: time.Hour * 24 * 7 * 365 * 5},
-		{interval: "1M", err: errors.New("time: unknown unit M in duration 1M")},
-		{interval: "invalid-duration", err: errors.New("time: invalid duration invalid-duration")},
+		{interval: "1d", duration: now.Sub(now.AddDate(0, 0, -1))},
+		{interval: "1w", duration: now.Sub(now.AddDate(0, 0, -7))},
+		{interval: "2w", duration: now.Sub(now.AddDate(0, 0, -14))},
+		{interval: "1M", duration: now.Sub(now.AddDate(0, -1, 0))},
+		{interval: "1y", duration: now.Sub(now.AddDate(-1, 0, 0))},
+		{interval: "5y", duration: now.Sub(now.AddDate(-5, 0, 0))},
+		{interval: "invalid-duration", err: "time: invalid duration invalid-duration"},
 	}
 
 	for i, tc := range tcs {
 		t.Run(fmt.Sprintf("testcase %d", i), func(t *testing.T) {
 			res, err := ParseInterval(tc.interval)
-			if err != nil && err.Error() != tc.err.Error() {
-				t.Fatalf("expected '%v' got '%v'", tc.err, err)
-			}
-			if res != tc.duration {
-				t.Errorf("expected %v got %v", tc.duration, res)
+			if tc.err == "" {
+				require.NoError(t, err, "interval %q", tc.interval)
+				require.Equal(t, tc.duration, res, "interval %q", tc.interval)
+			} else {
+				require.EqualError(t, err, tc.err, "interval %q", tc.interval)
 			}
 		})
 	}

pkg/tsdb/time_range.go

 package tsdb
 
 import (
-	"fmt"
 	"strconv"
 	"strings"
 	"time"
+
+	"github.com/timberio/go-datemath"
 )
 
 func NewTimeRange(from, to string) *TimeRange {
@@ -79,38 +80,26 @@ func tryParseUnixMsEpoch(val string) (time.Time, bool) {
 }
 
 func (tr *TimeRange) ParseFrom() (time.Time, error) {
-	if res, ok := tryParseUnixMsEpoch(tr.From); ok {
-		return res, nil
-	}
-
-	fromRaw := strings.Replace(tr.From, "now-", "", 1)
-	diff, err := time.ParseDuration("-" + fromRaw)
-	if err != nil {
-		return time.Time{}, err
-	}
-
-	return tr.now.Add(diff), nil
+	return parse(tr.From, tr.now, false)
 }
 
 func (tr *TimeRange) ParseTo() (time.Time, error) {
-	if tr.To == "now" {
-		return tr.now, nil
-	} else if strings.HasPrefix(tr.To, "now-") {
-		withoutNow := strings.Replace(tr.To, "now-", "", 1)
-
-		diff, err := time.ParseDuration("-" + withoutNow)
-		if err != nil {
-			return time.Time{}, nil
-		}
+	return parse(tr.To, tr.now, true)
+}
 
-		return tr.now.Add(diff), nil
+func parse(s string, now time.Time, withRoundUp bool) (time.Time, error) {
+	if res, ok := tryParseUnixMsEpoch(s); ok {
+		return res, nil
 	}
 
-	if res, ok := tryParseUnixMsEpoch(tr.To); ok {
-		return res, nil
+	withoutNow := strings.Replace(s, "now-", "", 1)
+
+	diff, err := time.ParseDuration("-" + withoutNow)
+	if err != nil {
+		return datemath.ParseAndEvaluate(s, datemath.WithNow(now), datemath.WithRoundUp(withRoundUp))
 	}
 
-	return time.Time{}, fmt.Errorf("cannot parse to value %s", tr.To)
+	return now.Add(diff), nil
 }
 
 // EpochPrecisionToMs converts epoch precision to millisecond, if needed.

pkg/tsdb/time_range_test.go

 package tsdb
 
 import (
+	"strconv"
 	"testing"
+
 	"time"
 
 	. "github.com/smartystreets/goconvey/convey"
@@ -20,7 +22,8 @@ func TestTimeRange(t *testing.T) {
 			}
 
 			Convey("5m ago ", func() {
-				fiveMinAgo, _ := time.ParseDuration("-5m")
+				fiveMinAgo, err := time.ParseDuration("-5m")
+				So(err, ShouldBeNil)
 				expected := now.Add(fiveMinAgo)
 
 				res, err := tr.ParseFrom()
@@ -43,7 +46,8 @@ func TestTimeRange(t *testing.T) {
 			}
 
 			Convey("5h ago ", func() {
-				fiveHourAgo, _ := time.ParseDuration("-5h")
+				fiveHourAgo, err := time.ParseDuration("-5h")
+				So(err, ShouldBeNil)
 				expected := now.Add(fiveHourAgo)
 
 				res, err := tr.ParseFrom()
@@ -52,7 +56,8 @@ func TestTimeRange(t *testing.T) {
 			})
 
 			Convey("now-10m ", func() {
-				tenMinAgo, _ := time.ParseDuration("-10m")
+				tenMinAgo, err := time.ParseDuration("-10m")
+				So(err, ShouldBeNil)
 				expected := now.Add(tenMinAgo)
 				res, err := tr.ParseTo()
 				So(err, ShouldBeNil)
@@ -60,7 +65,101 @@ func TestTimeRange(t *testing.T) {
 			})
 		})
 
-		Convey("can parse unix epocs", func() {
+		now, err := time.Parse(time.RFC3339Nano, "2020-03-26T15:12:56.000Z")
+		So(err, ShouldBeNil)
+		Convey("Can parse now-1M/M, now-1M/M", func() {
+			tr := TimeRange{
+				From: "now-1M/M",
+				To:   "now-1M/M",
+				now:  now,
+			}
+
+			Convey("from now-1M/M ", func() {
+				expected, err := time.Parse(time.RFC3339Nano, "2020-02-01T00:00:00.000Z")
+				So(err, ShouldBeNil)
+
+				res, err := tr.ParseFrom()
+				So(err, ShouldBeNil)
+				So(res, ShouldEqual, expected)
+			})
+
+			Convey("to now-1M/M ", func() {
+				expected, err := time.Parse(time.RFC3339Nano, "2020-02-29T23:59:59.999Z")
+				So(err, ShouldBeNil)
+
+				res, err := tr.ParseTo()
+				So(err, ShouldBeNil)
+				So(res, ShouldEqual, expected)
+			})
+		})
+
+		Convey("Can parse now-3d, now+3w", func() {
+			tr := TimeRange{
+				From: "now-3d",
+				To:   "now+3w",
+				now:  now,
+			}
+
+			Convey("now-3d ", func() {
+				expected, err := time.Parse(time.RFC3339Nano, "2020-03-23T15:12:56.000Z")
+				So(err, ShouldBeNil)
+
+				res, err := tr.ParseFrom()
+				So(err, ShouldBeNil)
+				So(res, ShouldEqual, expected)
+			})
+
+			Convey("now+3w ", func() {
+				expected, err := time.Parse(time.RFC3339Nano, "2020-04-16T15:12:56.000Z")
+				So(err, ShouldBeNil)
+
+				res, err := tr.ParseTo()
+				So(err, ShouldBeNil)
+				So(res, ShouldEqual, expected)
+			})
+		})
+
+		Convey("Can parse 1960-02-01T07:00:00.000Z, 1965-02-03T08:00:00.000Z", func() {
+			tr := TimeRange{
+				From: "1960-02-01T07:00:00.000Z",
+				To:   "1965-02-03T08:00:00.000Z",
+				now:  now,
+			}
+
+			Convey("1960-02-01T07:00:00.000Z ", func() {
+				expected, err := time.Parse(time.RFC3339Nano, "1960-02-01T07:00:00.000Z")
+				So(err, ShouldBeNil)
+
+				res, err := tr.ParseFrom()
+				So(err, ShouldBeNil)
+				So(res, ShouldEqual, expected)
+			})
+
+			Convey("1965-02-03T08:00:00.000Z ", func() {
+				expected, err := time.Parse(time.RFC3339Nano, "1965-02-03T08:00:00.000Z")
+				So(err, ShouldBeNil)
+
+				res, err := tr.ParseTo()
+				So(err, ShouldBeNil)
+				So(res, ShouldEqual, expected)
+			})
+		})
+
+		Convey("Can parse negative unix epochs", func() {
+			from := time.Date(1960, 2, 1, 7, 0, 0, 0, time.UTC)
+			to := time.Date(1965, 2, 3, 8, 0, 0, 0, time.UTC)
+			tr := NewTimeRange(strconv.FormatInt(from.UnixNano()/int64(time.Millisecond), 10), strconv.FormatInt(to.UnixNano()/int64(time.Millisecond), 10))
+
+			res, err := tr.ParseFrom()
+			So(err, ShouldBeNil)
+			So(res, ShouldEqual, from)
+
+			res, err = tr.ParseTo()
+			So(err, ShouldBeNil)
+			So(res, ShouldEqual, to)
+		})
+
+		Convey("can parse unix epochs", func() {
 			var err error
 			tr := TimeRange{
 				From: "1474973725473",