app/vmselect/promql: add label_uppercase(q, label1, ... labelN) and label_lowercase(q, label1, ... labelN) functions

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/936

app/vmselect/promql/exec_test.go

@@ -1100,6 +1100,62 @@ func TestExecSuccess(t *testing.T) {
 		resultExpected := []netstorage.Result{r1, r2, r3, r4, r5}
 		f(q, resultExpected)
 	})
+	t.Run(`label_uppercase`, func(t *testing.T) {
+		t.Parallel()
+		q := `label_uppercase(
+			label_set(time(), "foo", "bAr", "XXx", "yyy", "zzz", "abc"),
+			"foo", "XXx", "aaa"
+		)`
+		r := netstorage.Result{
+			MetricName: metricNameExpected,
+			Values:     []float64{1000, 1200, 1400, 1600, 1800, 2000},
+			Timestamps: timestampsExpected,
+		}
+		r.MetricName.Tags = []storage.Tag{
+			{
+				Key:   []byte("XXx"),
+				Value: []byte("YYY"),
+			},
+			{
+				Key:   []byte("foo"),
+				Value: []byte("BAR"),
+			},
+			{
+				Key:   []byte("zzz"),
+				Value: []byte("abc"),
+			},
+		}
+		resultExpected := []netstorage.Result{r}
+		f(q, resultExpected)
+	})
+	t.Run(`label_lowercase`, func(t *testing.T) {
+		t.Parallel()
+		q := `label_lowercase(
+			label_set(time(), "foo", "bAr", "XXx", "yyy", "zzz", "aBc"),
+			"foo", "XXx", "aaa"
+		)`
+		r := netstorage.Result{
+			MetricName: metricNameExpected,
+			Values:     []float64{1000, 1200, 1400, 1600, 1800, 2000},
+			Timestamps: timestampsExpected,
+		}
+		r.MetricName.Tags = []storage.Tag{
+			{
+				Key:   []byte("XXx"),
+				Value: []byte("yyy"),
+			},
+			{
+				Key:   []byte("foo"),
+				Value: []byte("bar"),
+			},
+			{
+				Key:   []byte("zzz"),
+				Value: []byte("aBc"),
+			},
+		}
+		resultExpected := []netstorage.Result{r}
+		f(q, resultExpected)
+	})
 	t.Run(`label_copy(new_tag)`, func(t *testing.T) {
 		t.Parallel()
 		q := `label_copy(
@@ -6231,6 +6287,8 @@ func TestExecError(t *testing.T) {
 	f(`label_transform(1, "foo", "invalid(regexp", "baz`)
 	f(`label_match(1, 2, 3)`)
 	f(`label_mismatch(1, 2, 3)`)
+	f(`label_uppercase()`)
+	f(`label_lowercase()`)
 	f(`alias(1, 2)`)
 	f(`aggr_over_time(1, 2)`)
 	f(`aggr_over_time(("foo", "bar"), 3)`)

app/vmselect/promql/transform.go

@@ -73,6 +73,8 @@ var transformFuncs = map[string]transformFunc{
 	// New funcs
 	"label_set":          transformLabelSet,
 	"label_map":          transformLabelMap,
+	"label_uppercase":    transformLabelUppercase,
+	"label_lowercase":    transformLabelLowercase,
 	"label_del":          transformLabelDel,
 	"label_keep":         transformLabelKeep,
 	"label_copy":         transformLabelCopy,
@@ -1196,6 +1198,42 @@ func transformLabelSet(tfa *transformFuncArg) ([]*timeseries, error) {
 	return rvs, nil
 }
 
+func transformLabelUppercase(tfa *transformFuncArg) ([]*timeseries, error) {
+	return transformLabelValueFunc(tfa, strings.ToUpper)
+}
+
+func transformLabelLowercase(tfa *transformFuncArg) ([]*timeseries, error) {
+	return transformLabelValueFunc(tfa, strings.ToLower)
+}
+
+func transformLabelValueFunc(tfa *transformFuncArg, f func(string) string) ([]*timeseries, error) {
+	args := tfa.args
+	if len(args) < 2 {
+		return nil, fmt.Errorf(`not enough args; got %d; want at least %d`, len(args), 2)
+	}
+	labels := make([]string, 0, len(args)-1)
+	for i := 1; i < len(args); i++ {
+		label, err := getString(args[i], i)
+		if err != nil {
+			return nil, err
+		}
+		labels = append(labels, label)
+	}
+
+	rvs := args[0]
+	for _, ts := range rvs {
+		mn := &ts.MetricName
+		for _, label := range labels {
+			dstValue := getDstValue(mn, label)
+			*dstValue = append((*dstValue)[:0], f(string(*dstValue))...)
+			if len(*dstValue) == 0 {
+				mn.RemoveTag(label)
+			}
+		}
+	}
+	return rvs, nil
+}
+
 func transformLabelMap(tfa *transformFuncArg) ([]*timeseries, error) {
 	args := tfa.args
 	if len(args) < 2 {

docs/CHANGELOG.md

@@ -3,6 +3,8 @@
 # tip
 
 * FEATURE: optimize Consul service discovery speed when discovering big number of services. See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/574
+* FEATURE: add `label_uppercase(q, label1, ... labelN)` and `label_lowercase(q, label1, ... labelN)` function to [MetricsQL](https://victoriametrics.github.io/MetricsQL.html)
+  for uppercasing and lowercasing values for the given labels. See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/936
 
 * BUGFIX: properly parse timestamps in OpenMetrics format - they are exposed as floating-point number in seconds instead of integer milliseconds
   unlike in Prometheus exposition format. See [the docs](https://github.com/OpenObservability/OpenMetrics/blob/master/specification/OpenMetrics.md#timestamps).

docs/MetricsQL.md

@@ -57,6 +57,8 @@ This functionality can be tried at [an editable Grafana dashboard](http://play-g
   - `alias(q, name)` for setting metric name across all the time series `q`.
   - `label_set(q, label1, value1, ... labelN, valueN)` for setting the given values for the given labels on `q`.
   - `label_map(q, label, srcValue1, dstValue1, ... srcValueN, dstValueN)` for mapping `label` values from `src*` to `dst*`.
+  - `label_uppercase(q, label1, ... labelN)` for uppercasing values for the given labels.
+  - `label_lowercase(q, label2, ... labelN)` for lowercasing value for the given labels.
   - `label_del(q, label1, ... labelN)` for deleting the given labels from `q`.
   - `label_keep(q, label1, ... labelN)` for deleting all the labels except the given labels from `q`.
   - `label_copy(q, src_label1, dst_label1, ... src_labelN, dst_labelN)` for copying label values from `src_*` to `dst_*`.

go.mod

@@ -8,7 +8,7 @@ require (
 	// like https://github.com/valyala/fasthttp/commit/996610f021ff45fdc98c2ce7884d5fa4e7f9199b
 	github.com/VictoriaMetrics/fasthttp v1.0.9
 	github.com/VictoriaMetrics/metrics v1.12.3
-	github.com/VictoriaMetrics/metricsql v0.7.3
+	github.com/VictoriaMetrics/metricsql v0.8.0
 	github.com/aws/aws-sdk-go v1.36.0
 	github.com/cespare/xxhash/v2 v2.1.1
 	github.com/golang/snappy v0.0.2

go.sum

@@ -45,8 +45,8 @@ github.com/VictoriaMetrics/fasthttp v1.0.9/go.mod h1:3SeUL4zwB/p/a9aEeRc6gdlbrtN
 github.com/VictoriaMetrics/metrics v1.12.2/go.mod h1:Z1tSfPfngDn12bTfZSCqArT3OPY3u88J12hSoOhuiRE=
 github.com/VictoriaMetrics/metrics v1.12.3 h1:Fe6JHC6MSEKa+BtLhPN8WIvS+HKPzMc2evEpNeCGy7I=
 github.com/VictoriaMetrics/metrics v1.12.3/go.mod h1:Z1tSfPfngDn12bTfZSCqArT3OPY3u88J12hSoOhuiRE=
-github.com/VictoriaMetrics/metricsql v0.7.3 h1:ReI+UBleCkGMmYDt69gsuGld71l1WpQDIlhgU1N5xQ8=
-github.com/VictoriaMetrics/metricsql v0.7.3/go.mod h1:ylO7YITho/Iw6P71oEaGyHbO94bGoGtzWfLGqFhMIg8=
+github.com/VictoriaMetrics/metricsql v0.8.0 h1:fUZWNjXYJhiCKoEXr86pM4RaAxfA3SqkAhJLe1gr/mo=
+github.com/VictoriaMetrics/metricsql v0.8.0/go.mod h1:ylO7YITho/Iw6P71oEaGyHbO94bGoGtzWfLGqFhMIg8=
 github.com/allegro/bigcache v1.2.1-0.20190218064605-e24eb225f156 h1:eMwmnE/GDgah4HI848JfFxHt+iPb26b4zyfspmqY0/8=
 github.com/allegro/bigcache v1.2.1-0.20190218064605-e24eb225f156/go.mod h1:Cb/ax3seSYIx7SuZdm2G2xzfwmv3TPSk2ucNfQESPXM=
 github.com/andybalholm/brotli v1.0.0/go.mod h1:loMXtMfwqflxFJPmdbJO0a3KNoPuLBgiu3qAvBg8x/Y=

vendor/github.com/VictoriaMetrics/metricsql/optimizer.go

@@ -110,7 +110,7 @@ func getMetricExprForOptimization(e Expr) *MetricExpr {
 	if IsTransformFunc(fe.Name) {
 		switch strings.ToLower(fe.Name) {
 		case "absent", "histogram_quantile", "label_join", "label_replace", "scalar", "vector",
-			"label_set", "label_map", "label_del", "label_keep", "label_copy",
+			"label_set", "label_map", "label_uppercase", "label_lowercase", "label_del", "label_keep", "label_copy",
 			"label_move", "label_transform", "label_value", "label_match", "label_mismatch",
 			"prometheus_buckets", "buckets_limit", "histogram_share", "union", "":
 			// metric expressions for these functions cannot be optimized.

vendor/github.com/VictoriaMetrics/metricsql/transform.go

@@ -39,6 +39,8 @@ var transformFuncs = map[string]bool{
 	// New funcs from MetricsQL
 	"label_set":          true,
 	"label_map":          true,
+	"label_uppercase":    true,
+	"label_lowercase":    true,
 	"label_del":          true,
 	"label_keep":         true,
 	"label_copy":         true,

vendor/modules.txt

@@ -16,7 +16,7 @@ github.com/VictoriaMetrics/fasthttp/fasthttputil
 github.com/VictoriaMetrics/fasthttp/stackless
 # github.com/VictoriaMetrics/metrics v1.12.3
 github.com/VictoriaMetrics/metrics
-# github.com/VictoriaMetrics/metricsql v0.7.3
+# github.com/VictoriaMetrics/metricsql v0.8.0
 github.com/VictoriaMetrics/metricsql
 github.com/VictoriaMetrics/metricsql/binaryop
 # github.com/aws/aws-sdk-go v1.36.0