MM-28859 Add feature flag managment system using split.io and remove viper. (#15954)

* Add feature flag managment system using split.io and remove viper.

* Fixing tests.

* Attempt to fix postgres tests.

* Fix watch filepath for advanced logging.

* Review fixes.

* Some error wrapping.

* Remove unessisary store interface.

* Desanitize SplitKey

* Simplify.

* Review feedback.

* Rename split mlog adatper to split logger.

* fsInner

* Style.

* Restore oldcfg test.

* Downgrading non-actionable feature flag errors to warnings.

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

vendor/github.com/splitio/go-split-commons/v2/util/metrics.go

@@ -0,0 +1,43 @@
+package util
+
+var latencyBuckets = [23]float64{
+	1.00,
+	1.50,
+	2.25,
+	3.38,
+	5.06,
+	7.59,
+	11.39,
+	17.09,
+	25.63,
+	38.44,
+	57.67,
+	86.50,
+	129.75,
+	194.62,
+	291.93,
+	437.89,
+	656.84,
+	985.26,
+	1477.89,
+	2216.84,
+	3325.26,
+	4987.89,
+	7481.83,
+}
+
+// Bucket returns the bucket where the received latency falls
+func Bucket(latency int64) int {
+	floatLatency := float64(latency) / 1000 // Convert to millisencods
+
+	index := 0
+	for index < len(latencyBuckets) && floatLatency > latencyBuckets[index] {
+		index++
+	}
+
+	if index == len(latencyBuckets) {
+		return index - 1
+	}
+
+	return index
+}

vendor/github.com/splitio/go-split-commons/v2/util/mode.go

@@ -0,0 +1,30 @@
+package util
+
+import (
+	"strings"
+
+	"github.com/splitio/go-split-commons/v2/conf"
+)
+
+// ShouldAddPreviousTime returns if previous time should be set up or not depending on operationMode
+func ShouldAddPreviousTime(managerConfig conf.ManagerConfig) bool {
+	switch strings.ToLower(managerConfig.OperationMode) {
+	case conf.ProducerSync:
+		fallthrough
+	case conf.Standalone:
+		return true
+	default:
+		return false
+	}
+}
+
+// ShouldBeOptimized returns if should dedupe impressions or not depending on configs
+func ShouldBeOptimized(managerConfig conf.ManagerConfig) bool {
+	if !ShouldAddPreviousTime(managerConfig) {
+		return false
+	}
+	if strings.ToLower(managerConfig.ImpressionsMode) == conf.ImpressionsModeOptimized {
+		return true
+	}
+	return false
+}

vendor/github.com/splitio/go-split-commons/v2/util/time.go

@@ -0,0 +1,11 @@
+package util
+
+import "time"
+
+const dedupWindowSizeMs = 3600 * 1000
+
+// TruncateTimeFrame truncates de time frame received with the time window
+func TruncateTimeFrame(timestampInNs int64) int64 {
+	timestampInMs := timestampInNs / int64(time.Millisecond)
+	return timestampInMs - (timestampInMs % dedupWindowSizeMs)
+}