From e79b2a3f66b1a296dc8894099b712280b1ccc8ed Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Agn=C3=A8s=20Toulet?=
 <35176601+AgnesToulet@users.noreply.github.com>
Date: Tue, 19 May 2020 08:52:43 +0200
Subject: [PATCH] Core: add location option to parse timerange (#24796)

* Core: add location option to parse timerange

* Extensions: add go-datemath to not break Enterprise
---
 pkg/tsdb/time_range.go      | 28 +++++++++++++-----
 pkg/tsdb/time_range_test.go | 59 +++++++++++++++++++++++++++++++++++++
 2 files changed, 80 insertions(+), 7 deletions(-)

diff --git a/pkg/tsdb/time_range.go b/pkg/tsdb/time_range.go
index 085604a44f5..eb855c0976b 100644
--- a/pkg/tsdb/time_range.go
+++ b/pkg/tsdb/time_range.go
@@ -80,23 +80,37 @@ func tryParseUnixMsEpoch(val string) (time.Time, bool) {
 }
 
 func (tr *TimeRange) ParseFrom() (time.Time, error) {
-	return parse(tr.From, tr.now, false)
+	return parse(tr.From, tr.now, false, nil)
 }
 
 func (tr *TimeRange) ParseTo() (time.Time, error) {
-	return parse(tr.To, tr.now, true)
+	return parse(tr.To, tr.now, true, nil)
 }
 
-func parse(s string, now time.Time, withRoundUp bool) (time.Time, error) {
+func (tr *TimeRange) ParseFromWithLocation(location *time.Location) (time.Time, error) {
+	return parse(tr.From, tr.now, false, location)
+}
+
+func (tr *TimeRange) ParseToWithLocation(location *time.Location) (time.Time, error) {
+	return parse(tr.To, tr.now, true, location)
+}
+
+func parse(s string, now time.Time, withRoundUp bool, location *time.Location) (time.Time, error) {
 	if res, ok := tryParseUnixMsEpoch(s); ok {
 		return res, nil
 	}
 
-	withoutNow := strings.Replace(s, "now-", "", 1)
-
-	diff, err := time.ParseDuration("-" + withoutNow)
+	diff, err := time.ParseDuration("-" + s)
 	if err != nil {
-		return datemath.ParseAndEvaluate(s, datemath.WithNow(now), datemath.WithRoundUp(withRoundUp))
+		options := []func(*datemath.Options){
+			datemath.WithNow(now),
+			datemath.WithRoundUp(withRoundUp),
+		}
+		if location != nil {
+			options = append(options, datemath.WithLocation(location))
+		}
+
+		return datemath.ParseAndEvaluate(s, options...)
 	}
 
 	return now.Add(diff), nil
diff --git a/pkg/tsdb/time_range_test.go b/pkg/tsdb/time_range_test.go
index 89de8e81463..4beb5914083 100644
--- a/pkg/tsdb/time_range_test.go
+++ b/pkg/tsdb/time_range_test.go
@@ -190,5 +190,64 @@ func TestTimeRange(t *testing.T) {
 			_, err = tr.ParseTo()
 			So(err, ShouldNotBeNil)
 		})
+
+		now, err = time.Parse(time.RFC3339Nano, "2020-07-26T15:12:56.000Z")
+		So(err, ShouldBeNil)
+
+		Convey("Can parse now-1M/M, now-1M/M with America/Chicago timezone", func() {
+			tr := TimeRange{
+				From: "now-1M/M",
+				To:   "now-1M/M",
+				now:  now,
+			}
+			location, err := time.LoadLocation("America/Chicago")
+			So(err, ShouldBeNil)
+
+			Convey("from now-1M/M ", func() {
+				expected, err := time.Parse(time.RFC3339Nano, "2020-06-01T00:00:00.000-05:00")
+				So(err, ShouldBeNil)
+
+				res, err := tr.ParseFromWithLocation(location)
+				So(err, ShouldBeNil)
+				So(res, ShouldEqual, expected)
+			})
+
+			Convey("to now-1M/M ", func() {
+				expected, err := time.Parse(time.RFC3339Nano, "2020-06-30T23:59:59.999-05:00")
+				So(err, ShouldBeNil)
+
+				res, err := tr.ParseToWithLocation(location)
+				So(err, ShouldBeNil)
+				So(res, ShouldEqual, expected)
+			})
+		})
+
+		Convey("Can parse now-3h, now+2h with America/Chicago timezone", func() {
+			tr := TimeRange{
+				From: "now-3h",
+				To:   "now+2h",
+				now:  now,
+			}
+			location, err := time.LoadLocation("America/Chicago")
+			So(err, ShouldBeNil)
+
+			Convey("now-3h ", func() {
+				expected, err := time.Parse(time.RFC3339Nano, "2020-07-26T07:12:56.000-05:00")
+				So(err, ShouldBeNil)
+
+				res, err := tr.ParseFromWithLocation(location)
+				So(err, ShouldBeNil)
+				So(res, ShouldEqual, expected)
+			})
+
+			Convey("now+2h ", func() {
+				expected, err := time.Parse(time.RFC3339Nano, "2020-07-26T12:12:56.000-05:00")
+				So(err, ShouldBeNil)
+
+				res, err := tr.ParseToWithLocation(location)
+				So(err, ShouldBeNil)
+				So(res, ShouldEqual, expected)
+			})
+		})
 	})
 }