Merge #42781

42781: sql: Fix for invalid value for parameter "TimeZone": "GMT-08:00" #41776 r=otan a=droidnoob

Resolves #41776

Previously, the inputs starting with `UTC` and `GMT` would cause error.
Postgres supports inputs like this. So adding support for
these inputs was necessary.
sql: Added a check to convert the strings to offset.
timeutil: added a function to convert input to offset seconds.
Added unit tests. Added a regex to accept the above inputs.
Cleaned the code.

Release note (sql change): `SET TIME ZONE` now accepts inputs
beginning with `GMT` and `UTC`, such as `GMT+5` and
`UTC-3:59`. This was previously unsupported.


@otan 

Co-authored-by: Ananthakrishnan <[email protected]>

pkg/sql/logictest/testdata/logic_test/timestamp

@@ -192,3 +192,14 @@ query R
 SELECT extract(timezone FROM '2001-01-01 13:00:00+01:15'::timestamptz)
 ----
 10800
+
+
+subtest regression_41776
+
+statement ok
+SET TIME ZONE 'GMT+1'
+
+query T
+SELECT '2001-01-01 00:00:00'::TIMESTAMP::TIMESTAMPTZ
+----
+2001-01-01 00:00:00 +0100 +0100

pkg/sql/set_var.go

@@ -222,8 +222,12 @@ func timeZoneVarGetStringVal(
 			if err1 != nil {
 				loc, err1 = timeutil.LoadLocation(strings.ToTitle(location))
 				if err1 != nil {
-					return "", wrapSetVarError("timezone", values[0].String(),
-						"cannot find time zone %q: %v", location, err)
+					var ok bool
+					offset, ok = timeutil.TimeZoneOffsetStringConversion(location)
+					if !ok {
+						return "", wrapSetVarError("timezone", values[0].String(),
+							"cannot find time zone %q: %v", location, err)
+					}
 				}
 			}
 		}

pkg/util/timeutil/time_zone_util.go

@@ -12,12 +12,18 @@ package timeutil
 
 import (
 	"fmt"
+	"regexp"
 	"strconv"
 	"strings"
 	"time"
 )
 
-const fixedOffsetPrefix string = "fixed offset:"
+const (
+	fixedOffsetPrefix = "fixed offset:"
+	offsetBoundSecs   = 167*60*60 + 59*60
+)
+
+var timezoneOffsetRegex = regexp.MustCompile(`(?i)(GMT|UTC)([+-])(\d{1,3}(:[0-5]?\d){0,2})\b$`)
 
 // FixedOffsetTimeZoneToLocation creates a time.Location with a set offset and
 // with a name that can be marshaled by crdb between nodes.
@@ -68,3 +74,44 @@ func ParseFixedOffsetTimeZone(location string) (offset int, origRepr string, suc
 	}
 	return offset, strings.TrimSuffix(strings.TrimPrefix(origRepr, "("), ")"), true
 }
+
+// TimeZoneOffsetStringConversion converts a time string to offset seconds.
+// Supported time zone strings: GMT/UTC±[00:00:00 - 169:59:00].
+// Seconds/minutes omittable and is case insensitive.
+func TimeZoneOffsetStringConversion(s string) (offset int64, ok bool) {
+	submatch := timezoneOffsetRegex.FindStringSubmatch(strings.ReplaceAll(s, " ", ""))
+	if len(submatch) == 0 {
+		return 0, false
+	}
+	prefix := string(submatch[0][3])
+	timeString := string(submatch[3])
+
+	var (
+		hoursString   = "0"
+		minutesString = "0"
+		secondsString = "0"
+	)
+	if strings.Contains(timeString, ":") {
+		offsets := strings.Split(timeString, ":")
+		hoursString, minutesString = offsets[0], offsets[1]
+		if len(offsets) == 3 {
+			secondsString = offsets[2]
+		}
+	} else {
+		hoursString = timeString
+	}
+
+	hours, _ := strconv.ParseInt(hoursString, 10, 64)
+	minutes, _ := strconv.ParseInt(minutesString, 10, 64)
+	seconds, _ := strconv.ParseInt(secondsString, 10, 64)
+	offset = (hours * 60 * 60) + (minutes * 60) + seconds
+
+	if prefix == "-" {
+		offset *= -1
+	}
+
+	if offset > offsetBoundSecs || offset < -offsetBoundSecs {
+		return 0, false
+	}
+	return offset, true
+}

pkg/util/timeutil/time_zone_util_test.go

@@ -0,0 +1,48 @@
+// Copyright 2019 The Cockroach Authors.
+//
+// Use of this software is governed by the Business Source License
+// included in the file licenses/BSL.txt.
+//
+// As of the Change Date specified in that file, in accordance with
+// the Business Source License, use of this software will be governed
+// by the Apache License, Version 2.0, included in the file
+// licenses/APL.txt.
+
+package timeutil
+
+import "testing"
+
+func TestTimeZoneOffsetStringConversion(t *testing.T) {
+	testCases := []struct {
+		timezone   string
+		offsetSecs int64
+		ok         bool
+	}{
+		{`GMT+00:00`, 0, true},
+		{`UTC-1:00:00`, -3600, true},
+		{`UTC-1:0:00`, -3600, true},
+		{`UTC+15:59:0`, 57540, true},
+		{` GMT +167:59:00  `, 604740, true},
+		{`GMT-15:59:59`, -57599, true},
+		{`GMT-06:59`, -25140, true},
+		{`GMT+167:59:00`, 604740, true},
+		{`GMT+ 167: 59:0`, 604740, true},
+		{`GMT+5`, 18000, true},
+		{`UTC+5:9`, 5*60*60 + 9*60, true},
+		{`UTC-5:9:1`, -(5*60*60 + 9*60 + 1), true},
+		{`GMT-15:59:5Z`, 0, false},
+		{`GMT-15:99:1`, 0, false},
+		{`GMT+6:`, 0, false},
+		{`GMT-6:00:`, 0, false},
+		{`GMT+168:00:00`, 0, false},
+		{`GMT-170:00:59`, 0, false},
+	}
+
+	for i, testCase := range testCases {
+		offset, ok := TimeZoneOffsetStringConversion(testCase.timezone)
+		if offset != testCase.offsetSecs || ok != testCase.ok {
+			t.Errorf("%d: Expected offset: %d, success: %v for time %s, but got offset: %d, success: %v",
+				i, testCase.offsetSecs, testCase.ok, testCase.timezone, offset, ok)
+		}
+	}
+}