Enable promql-per-step-stats feature.

Harkishen-Singh · Harkishen-Singh · commit a5ffe9db7431 · 2022-05-25T14:39:22.000+05:30
Signed-off-by: Harkishen-Singh &lt;harkishensingh@hotmail.com&gt;

This commit enables the `promql-per-step-stats` feature. This is done by
passing `&amp;QueryOpts{EnablePerStepStats: true}` when creating a query.
This result goes with logical AND with
`-enable-feature=promql-per-step-stats` applied as Promscale starts.
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -15,6 +15,9 @@ We use the following categories for changes:
 
 ## [Unreleased]
 
+### Added
+- `-enable-feature=promql-per-step-stats` feature for statistics in PromQL evaluation
+
 ## [0.11.0] - 2022-05-11
 
 ## Added
diff --git a/docs/configuration.md b/docs/configuration.md
@@ -46,7 +46,7 @@ The following subsections cover all CLI flags which promscale supports. You can
 |---------------------------------|:------------------------------:|:-------------:|:-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
 | cache.memory-target             | unsigned-integer or percentage |      80%      | Target for max amount of memory to use. Specified in bytes or as a percentage of system memory (e.g. 80%).                                                                                                                                                                                                                                                                                                                                                 |
 | config                          |             string             |  config.yml   | YAML configuration file path for Promscale.                                                                                                                                                                                                                                                                                                                                                                                                                |
-| enable-feature                  |             string             |      ""       | Enable one or more experimental promscale features (as a comma-separated list). Current experimental features are `promql-at-modifier`, and `promql-negative-offset`. For more information, please consult the following resources: [promql-at-modifier](https://prometheus.io/docs/prometheus/latest/feature_flags/#modifier-in-promql), [promql-negative-offset](https://prometheus.io/docs/prometheus/latest/feature_flags/#negative-offset-in-promql). |
+| enable-feature                  |             string             |      ""       | Enable one or more experimental promscale features (as a comma-separated list). Current experimental features are `promql-at-modifier`, `promql-negative-offset` and `promql-per-step-stats`. For more information, please consult the following resources: [promql-at-modifier](https://prometheus.io/docs/prometheus/latest/feature_flags/#modifier-in-promql), [promql-negative-offset](https://prometheus.io/docs/prometheus/latest/feature_flags/#negative-offset-in-promql), [promql-per-step-stats](https://prometheus.io/docs/prometheus/latest/feature_flags/#per-step-stats). |
 | thanos.store-api.server-address |             string             | "" (disabled) | Address to listen on for Thanos Store API endpoints.                                                                                                                                                                                                                                                                                                                                                                                                       |
 | tracing.otlp.server-address     |             string             |    ":9202"    | Address to listen on for OpenTelemetry OTLP GRPC server.                                                                                                                                                                                                                                                                                                                                                                                                   |
 
diff --git a/pkg/api/query.go b/pkg/api/query.go
@@ -50,7 +50,7 @@ func queryHandler(queryEngine *promql.Engine, queryable promql.Queryable, update
 			defer cancel()
 		}
 
-		qry, err := queryEngine.NewInstantQuery(queryable, nil, r.FormValue("query"), ts)
+		qry, err := queryEngine.NewInstantQuery(queryable, &promql.QueryOpts{EnablePerStepStats: true}, r.FormValue("query"), ts)
 		if err != nil {
 			log.Error("msg", "Query error", "err", err.Error())
 			respondError(w, http.StatusBadRequest, err, "bad_data")
diff --git a/pkg/api/query_range.go b/pkg/api/query_range.go
@@ -89,7 +89,7 @@ func queryRange(promqlConf *query.Config, queryEngine *promql.Engine, queryable
 
 		qry, err := queryEngine.NewRangeQuery(
 			queryable,
-			nil,
+			&promql.QueryOpts{EnablePerStepStats: true},
 			r.FormValue("query"),
 			start,
 			end,
diff --git a/pkg/query/config.go b/pkg/query/config.go
@@ -42,7 +42,7 @@ type Config struct {
 }
 
 func ParseFlags(fs *flag.FlagSet, cfg *Config) *Config {
-	fs.Var(&cfg.PromscaleEnabledFeatureList, "enable-feature", "Enable beta/experimental features as a comma-separated list. Currently the following values can be passed: promql-at-modifier, promql-negative-offset")
+	fs.Var(&cfg.PromscaleEnabledFeatureList, "enable-feature", "Enable beta/experimental features as a comma-separated list. Currently the following values can be passed: promql-at-modifier, promql-negative-offset, promql-per-step-stats")
 
 	fs.DurationVar(&cfg.MaxQueryTimeout, "metrics.promql.query-timeout", DefaultQueryTimeout, "Maximum time a query may take before being aborted. This option sets both the default and maximum value of the 'timeout' parameter in "+
 		"'/api/v1/query.*' endpoints.")
@@ -61,7 +61,7 @@ func Validate(cfg *Config) error {
 	cfg.EnabledFeatureMap = make(map[string]struct{})
 	for _, f := range cfg.PromscaleEnabledFeatureList {
 		switch f {
-		case "promql-at-modifier", "promql-negative-offset":
+		case "promql-at-modifier", "promql-negative-offset", "promql-per-step-stats":
 			cfg.EnabledFeatureMap[f] = struct{}{}
 		case "tracing":
 			log.Error("msg", "tracing feature is now on by default, no need to use it with --enable-feature flag")
diff --git a/pkg/query/query_engine.go b/pkg/query/query_engine.go
@@ -21,9 +21,10 @@ func NewEngine(logger log.Logger, queryTimeout, lookBackDelta, subqueryDefaultSt
 		LookbackDelta:            lookBackDelta,
 		NoStepSubqueryIntervalFn: func(int64) int64 { return durationMilliseconds(subqueryDefaultStepInterval) },
 	}
-	// todo (harkishen): add promql-per-step-stats feature
+
 	_, engineOpts.EnableAtModifier = enabledFeaturesMap["promql-at-modifier"]
 	_, engineOpts.EnableNegativeOffset = enabledFeaturesMap["promql-negative-offset"]
+	_, engineOpts.EnablePerStepStats = enabledFeaturesMap["promql-per-step-stats"]
 	return promql.NewEngine(engineOpts), nil
 }
 
diff --git a/pkg/runner/flags_test.go b/pkg/runner/flags_test.go
@@ -155,14 +155,15 @@ func TestParseFlags(t *testing.T) {
 		},
 		{
 			name: "enable feature should populate map of enabled features",
-			args: []string{"-enable-feature", "tracing,promql-at-modifier,promql-negative-offset", "-tracing.otlp.server-address", "someaddress"},
+			args: []string{"-enable-feature", "tracing,promql-at-modifier,promql-negative-offset,promql-per-step-stats", "-tracing.otlp.server-address", "someaddress"},
 			result: func(c Config) Config {
 				c.OTLPGRPCListenAddr = "someaddress"
 				c.PromQLCfg.EnabledFeatureMap = map[string]struct{}{
 					"promql-at-modifier":     {},
 					"promql-negative-offset": {},
+					"promql-per-step-stats":  {},
 				}
-				c.PromQLCfg.PromscaleEnabledFeatureList = []string{"tracing", "promql-at-modifier", "promql-negative-offset"}
+				c.PromQLCfg.PromscaleEnabledFeatureList = []string{"tracing", "promql-at-modifier", "promql-negative-offset", "promql-per-step-stats"}
 				return c
 			},
 		},

Original file line number	Diff line number	Diff line change
`@@ -50,7 +50,7 @@ func queryHandler(queryEngine *promql.Engine, queryable promql.Queryable, update`
`50`	`50`	`defer cancel()`
`51`	`51`	`}`
`52`	`52`
`53`		`- qry, err := queryEngine.NewInstantQuery(queryable, nil, r.FormValue("query"), ts)`
	`53`	`+ qry, err := queryEngine.NewInstantQuery(queryable, &promql.QueryOpts{EnablePerStepStats: true}, r.FormValue("query"), ts)`
`54`	`54`	`if err != nil {`
`55`	`55`	`log.Error("msg", "Query error", "err", err.Error())`
`56`	`56`	`respondError(w, http.StatusBadRequest, err, "bad_data")`
Original file line number	Diff line number	Diff line change
`@@ -21,9 +21,10 @@ func NewEngine(logger log.Logger, queryTimeout, lookBackDelta, subqueryDefaultSt`
`21`	`21`	`LookbackDelta: lookBackDelta,`
`22`	`22`	`NoStepSubqueryIntervalFn: func(int64) int64 { return durationMilliseconds(subqueryDefaultStepInterval) },`
`23`	`23`	`}`
`24`		`- // todo (harkishen): add promql-per-step-stats feature`
	`24`	`+`
`25`	`25`	`_, engineOpts.EnableAtModifier = enabledFeaturesMap["promql-at-modifier"]`
`26`	`26`	`_, engineOpts.EnableNegativeOffset = enabledFeaturesMap["promql-negative-offset"]`
	`27`	`+ _, engineOpts.EnablePerStepStats = enabledFeaturesMap["promql-per-step-stats"]`
`27`	`28`	`return promql.NewEngine(engineOpts), nil`
`28`	`29`	`}`
`29`	`30`