change fillmode from last to previous

docs/sources/features/datasources/mssql.md

@@ -83,7 +83,7 @@ Macro example | Description
 *$__timeGroup(dateColumn,'5m'[, fillvalue])* | Will be replaced by an expression usable in GROUP BY clause. Providing a *fillValue* of *NULL* or *floating value* will automatically fill empty series in timerange with that value. <br/>For example, *CAST(ROUND(DATEDIFF(second, '1970-01-01', time_column)/300.0, 0) as bigint)\*300*.
 *$__timeGroup(dateColumn,'5m', 0)* | Same as above but with a fill parameter so missing points in that series will be added by grafana and 0 will be used as value.
 *$__timeGroup(dateColumn,'5m', NULL)* | Same as above but NULL will be used as value for missing points.
-*$__timeGroup(dateColumn,'5m', last)* | Same as above but the last seen value in that series will be used as fill value if no value has been seen yet NULL will be used (only available in Grafana 5.3+).
+*$__timeGroup(dateColumn,'5m', previous)* | Same as above but the previous value in that series will be used as fill value if no value has been seen yet NULL will be used (only available in Grafana 5.3+).
 *$__timeGroupAlias(dateColumn,'5m')* | Will be replaced identical to $__timeGroup but with an added column alias (only available in Grafana 5.3+).
 *$__unixEpochFilter(dateColumn)* | Will be replaced by a time range filter using the specified column name with times represented as unix timestamp. For example, *dateColumn > 1494410783 AND dateColumn < 1494497183*
 *$__unixEpochFrom()* | Will be replaced by the start of the currently active time selection as unix timestamp. For example, *1494410783*

docs/sources/features/datasources/mysql.md

@@ -66,7 +66,7 @@ Macro example | Description
 *$__timeGroup(dateColumn,'5m')* | Will be replaced by an expression usable in GROUP BY clause. For example, *cast(cast(UNIX_TIMESTAMP(dateColumn)/(300) as signed)*300 as signed),*
 *$__timeGroup(dateColumn,'5m', 0)* | Same as above but with a fill parameter so missing points in that series will be added by grafana and 0 will be used as value.
 *$__timeGroup(dateColumn,'5m', NULL)* | Same as above but NULL will be used as value for missing points.
-*$__timeGroup(dateColumn,'5m', last)* | Same as above but the last seen value in that series will be used as fill value if no value has been seen yet NULL will be used (only available in Grafana 5.3+).
+*$__timeGroup(dateColumn,'5m', previous)* | Same as above but the previous value in that series will be used as fill value if no value has been seen yet NULL will be used (only available in Grafana 5.3+).
 *$__timeGroupAlias(dateColumn,'5m')* | Will be replaced identical to $__timeGroup but with an added column alias (only available in Grafana 5.3+).
 *$__unixEpochFilter(dateColumn)* | Will be replaced by a time range filter using the specified column name with times represented as unix timestamp. For example, *dateColumn > 1494410783 AND dateColumn < 1494497183*
 *$__unixEpochFrom()* | Will be replaced by the start of the currently active time selection as unix timestamp. For example, *1494410783*

docs/sources/features/datasources/postgres.md

@@ -63,8 +63,7 @@ Macro example | Description
 *$__timeGroup(dateColumn,'5m')* | Will be replaced by an expression usable in GROUP BY clause. For example, *(extract(epoch from dateColumn)/300)::bigint*300*
 *$__timeGroup(dateColumn,'5m', 0)* | Same as above but with a fill parameter so missing points in that series will be added by grafana and 0 will be used as value.
 *$__timeGroup(dateColumn,'5m', NULL)* | Same as above but NULL will be used as value for missing points.
-*$__timeGroup(dateColumn,'5m', last)* | Same as above but the last seen value in that series will be used as fill value if no value has been seen yet NULL will be used.
-*$__timeGroup(dateColumn,'5m', last)* | Same as above but the last seen value in that series will be used as fill value if no value has been seen yet NULL will be used (only available in Grafana 5.3+).
+*$__timeGroup(dateColumn,'5m', previous)* | Same as above but the previous value in that series will be used as fill value if no value has been seen yet NULL will be used (only available in Grafana 5.3+).
 *$__timeGroupAlias(dateColumn,'5m')* | Will be replaced identical to $__timeGroup but with an added column alias (only available in Grafana 5.3+).
 *$__unixEpochFilter(dateColumn)* | Will be replaced by a time range filter using the specified column name with times represented as unix timestamp. For example, *dateColumn >= 1494410783 AND dateColumn <= 1494497183*
 *$__unixEpochFrom()* | Will be replaced by the start of the currently active time selection as unix timestamp. For example, *1494410783*

pkg/tsdb/mssql/macros.go

@@ -102,8 +102,8 @@ func (m *msSqlMacroEngine) evaluateMacro(name string, args []string) (string, er
 			switch args[2] {
 			case "NULL":
 				m.query.Model.Set("fillMode", "null")
-			case "last":
-				m.query.Model.Set("fillMode", "last")
+			case "previous":
+				m.query.Model.Set("fillMode", "previous")
 			default:
 				m.query.Model.Set("fillMode", "value")
 				floatVal, err := strconv.ParseFloat(args[2], 64)

pkg/tsdb/mssql/macros_test.go

@@ -85,8 +85,8 @@ func TestMacroEngine(t *testing.T) {
 				So(fillInterval, ShouldEqual, 5*time.Minute.Seconds())
 			})
 
-			Convey("interpolate __timeGroup function with fill (value = last)", func() {
-				_, err := engine.Interpolate(query, timeRange, "GROUP BY $__timeGroup(time_column,'5m', last)")
+			Convey("interpolate __timeGroup function with fill (value = previous)", func() {
+				_, err := engine.Interpolate(query, timeRange, "GROUP BY $__timeGroup(time_column,'5m', previous)")
 
 				fill := query.Model.Get("fill").MustBool()
 				fillMode := query.Model.Get("fillMode").MustString()
@@ -94,7 +94,7 @@ func TestMacroEngine(t *testing.T) {
 
 				So(err, ShouldBeNil)
 				So(fill, ShouldBeTrue)
-				So(fillMode, ShouldEqual, "last")
+				So(fillMode, ShouldEqual, "previous")
 				So(fillInterval, ShouldEqual, 5*time.Minute.Seconds())
 			})
 

pkg/tsdb/mysql/macros.go

@@ -97,8 +97,8 @@ func (m *mySqlMacroEngine) evaluateMacro(name string, args []string) (string, er
 			switch args[2] {
 			case "NULL":
 				m.query.Model.Set("fillMode", "null")
-			case "last":
-				m.query.Model.Set("fillMode", "last")
+			case "previous":
+				m.query.Model.Set("fillMode", "previous")
 			default:
 				m.query.Model.Set("fillMode", "value")
 				floatVal, err := strconv.ParseFloat(args[2], 64)

pkg/tsdb/mysql/mysql_test.go

@@ -321,12 +321,12 @@ func TestMySQL(t *testing.T) {
 				So(points[3][0].Float64, ShouldEqual, 1.5)
 			})
 
-			Convey("When doing a metric query using timeGroup with last fill enabled", func() {
+			Convey("When doing a metric query using timeGroup with previous fill enabled", func() {
 				query := &tsdb.TsdbQuery{
 					Queries: []*tsdb.Query{
 						{
 							Model: simplejson.NewFromAny(map[string]interface{}{
-								"rawSql": "SELECT $__timeGroup(time, '5m', last) as time_sec, avg(value) as value FROM metric GROUP BY 1 ORDER BY 1",
+								"rawSql": "SELECT $__timeGroup(time, '5m', previous) as time_sec, avg(value) as value FROM metric GROUP BY 1 ORDER BY 1",
 								"format": "time_series",
 							}),
 							RefId: "A",

pkg/tsdb/postgres/macros.go

@@ -119,8 +119,8 @@ func (m *postgresMacroEngine) evaluateMacro(name string, args []string) (string,
 			switch args[2] {
 			case "NULL":
 				m.query.Model.Set("fillMode", "null")
-			case "last":
-				m.query.Model.Set("fillMode", "last")
+			case "previous":
+				m.query.Model.Set("fillMode", "previous")
 			default:
 				m.query.Model.Set("fillMode", "value")
 				floatVal, err := strconv.ParseFloat(args[2], 64)

pkg/tsdb/postgres/postgres_test.go

@@ -303,12 +303,12 @@ func TestPostgres(t *testing.T) {
 			})
 		})
 
-		Convey("When doing a metric query using timeGroup with last fill enabled", func() {
+		Convey("When doing a metric query using timeGroup with previous fill enabled", func() {
 			query := &tsdb.TsdbQuery{
 				Queries: []*tsdb.Query{
 					{
 						Model: simplejson.NewFromAny(map[string]interface{}{
-							"rawSql": "SELECT $__timeGroup(time, '5m', last), avg(value) as value FROM metric GROUP BY 1 ORDER BY 1",
+							"rawSql": "SELECT $__timeGroup(time, '5m', previous), avg(value) as value FROM metric GROUP BY 1 ORDER BY 1",
 							"format": "time_series",
 						}),
 						RefId: "A",

pkg/tsdb/sql_engine.go

@@ -274,14 +274,14 @@ func (e *sqlQueryEndpoint) transformToTimeSeries(query *Query, rows *core.Rows,
 	fillMissing := query.Model.Get("fill").MustBool(false)
 	var fillInterval float64
 	fillValue := null.Float{}
-	fillLast := false
+	fillPrevious := false
 
 	if fillMissing {
 		fillInterval = query.Model.Get("fillInterval").MustFloat64() * 1000
 		switch query.Model.Get("fillMode").MustString() {
 		case "null":
-		case "last":
-			fillLast = true
+		case "previous":
+			fillPrevious = true
 		case "value":
 			fillValue.Float64 = query.Model.Get("fillValue").MustFloat64()
 			fillValue.Valid = true
@@ -358,7 +358,7 @@ func (e *sqlQueryEndpoint) transformToTimeSeries(query *Query, rows *core.Rows,
 					intervalStart = series.Points[len(series.Points)-1][1].Float64 + fillInterval
 				}
 
-				if fillLast {
+				if fillPrevious {
 					if len(series.Points) > 0 {
 						fillValue = series.Points[len(series.Points)-1][0]
 					} else {
@@ -391,7 +391,7 @@ func (e *sqlQueryEndpoint) transformToTimeSeries(query *Query, rows *core.Rows,
 			intervalStart := series.Points[len(series.Points)-1][1].Float64
 			intervalEnd := float64(tsdbQuery.TimeRange.MustGetTo().UnixNano() / 1e6)
 
-			if fillLast {
+			if fillPrevious {
 				if len(series.Points) > 0 {
 					fillValue = series.Points[len(series.Points)-1][0]
 				} else {