Merge pull request #258 from splitio/fallback-treatment

[FME-11063] Release Fallback treatment

Author: nmayorsplit

.github/workflows/ci.yml

@@ -35,7 +35,7 @@ jobs:
 
       - name: SonarQube Scan (Push)
         if: ${{ github.event_name == 'push' }}
-        uses: SonarSource/sonarcloud-github[email protected]
+        uses: SonarSource/sonarqube-scan[email protected]
         env:
           SONAR_TOKEN: ${{ secrets.SONARQUBE_TOKEN }}
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
@@ -46,7 +46,7 @@ jobs:
 
       - name: SonarQube Scan (Pull Request)
         if: ${{ github.event_name == 'pull_request' }}
-        uses: SonarSource/sonarcloud-github[email protected]
+        uses: SonarSource/sonarqube-scan[email protected]
         env:
           SONAR_TOKEN: ${{ secrets.SONARQUBE_TOKEN }}
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

CHANGES

@@ -1,3 +1,8 @@
+9.0.0 (Nov 21, 2025)
+- BREAKING CHANGE:
+    - Changed new evaluator.
+- Added fallback treatment.
+
 8.0.0 (Nov 10, 2025)
 - BREAKING CHANGE:
     - Changed Rule Based Segment and Feature Flag storages.

conf/conf.go

@@ -2,6 +2,8 @@ package conf
 
 import (
 	"crypto/tls"
+
+	"github.com/splitio/go-split-commons/v9/dtos"
 )
 
 // RedisConfig struct is used to cofigure the redis parameters
@@ -89,6 +91,7 @@ type AdvancedConfig struct {
 	FlagsSpecVersion       string
 	LargeSegment           *LargeSegmentConfig
 	RulesConfig            *RulesConfig
+	FallbackTreatment      dtos.FallbackTreatmentConfig
 }
 
 type LargeSegmentConfig struct {

dtos/fallbacktreatment.go

@@ -0,0 +1,68 @@
+package dtos
+
+const (
+	labelPrefix = "fallback - "
+)
+
+type FallbackTreatment struct {
+	Treatment *string
+	Config    *string
+	label     *string
+}
+
+func (f *FallbackTreatment) Label() *string {
+	return f.label
+}
+
+type FallbackTreatmentConfig struct {
+	GlobalFallbackTreatment *FallbackTreatment
+	ByFlagFallbackTreatment map[string]FallbackTreatment
+}
+
+type FallbackTreatmentCalculator interface {
+	Resolve(flagName string, label *string) FallbackTreatment
+}
+
+type FallbackTreatmentCalculatorImp struct {
+	fallbackTreatmentConfig *FallbackTreatmentConfig
+}
+
+func NewFallbackTreatmentCalculatorImp(fallbackTreatmentConfig *FallbackTreatmentConfig) FallbackTreatmentCalculator {
+	return &FallbackTreatmentCalculatorImp{
+		fallbackTreatmentConfig: fallbackTreatmentConfig,
+	}
+}
+
+func (f *FallbackTreatmentCalculatorImp) Resolve(flagName string, label *string) FallbackTreatment {
+	if f.fallbackTreatmentConfig != nil {
+		if byFlag := f.fallbackTreatmentConfig.ByFlagFallbackTreatment; byFlag != nil {
+			if val, ok := byFlag[flagName]; ok {
+				return FallbackTreatment{
+					Treatment: val.Treatment,
+					Config:    val.Config,
+					label:     f.resolveLabel(label),
+				}
+			}
+		}
+		if f.fallbackTreatmentConfig.GlobalFallbackTreatment != nil {
+			return FallbackTreatment{
+				Treatment: f.fallbackTreatmentConfig.GlobalFallbackTreatment.Treatment,
+				Config:    f.fallbackTreatmentConfig.GlobalFallbackTreatment.Config,
+				label:     f.resolveLabel(label),
+			}
+		}
+	}
+	controlTreatment := "control"
+	return FallbackTreatment{
+		Treatment: &controlTreatment,
+		label:     label,
+	}
+}
+
+func (f *FallbackTreatmentCalculatorImp) resolveLabel(label *string) *string {
+	if label == nil {
+		return nil
+	}
+	result := labelPrefix + *label
+	return &result
+}

dtos/fallbacktreatment_test.go

@@ -0,0 +1,65 @@
+package dtos
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestFallbackTreatmentCalculatorResolve(t *testing.T) {
+	// Initial setup with both global and flag-specific treatments
+	stringConfig := "flag1_config"
+	globalTreatment := "global_treatment"
+	flag1Treatment := "flag1_treatment"
+	config := &FallbackTreatmentConfig{
+		GlobalFallbackTreatment: &FallbackTreatment{
+			Treatment: &globalTreatment,
+		},
+		ByFlagFallbackTreatment: map[string]FallbackTreatment{
+			"flag1": {
+				Treatment: &flag1Treatment,
+				Config:    &stringConfig,
+			},
+		},
+	}
+	calc := NewFallbackTreatmentCalculatorImp(config)
+
+	// Test flag-specific treatment with label
+	label := "some_label"
+	result := calc.Resolve("flag1", &label)
+	assert.Equal(t, "flag1_treatment", *result.Treatment)
+	assert.Equal(t, &stringConfig, result.Config)
+	assert.Equal(t, "fallback - some_label", *result.label)
+
+	// Test fallback to global treatment when flag not found
+	result = calc.Resolve("flag2", &label)
+	assert.Equal(t, "global_treatment", *result.Treatment)
+	assert.Nil(t, result.Config)
+	assert.Equal(t, "fallback - some_label", *result.label)
+
+	// Test nil label handling
+	result = calc.Resolve("flag1", nil)
+	assert.Equal(t, "flag1_treatment", *result.Treatment)
+	assert.Equal(t, &stringConfig, result.Config)
+	assert.Nil(t, result.label)
+
+	// Test default control when no config
+	calcNoConfig := NewFallbackTreatmentCalculatorImp(nil)
+	result = calcNoConfig.Resolve("flag1", &label)
+	assert.Equal(t, "control", *result.Treatment)
+	assert.Nil(t, result.Config)
+	assert.Equal(t, "some_label", *result.label)
+
+	// Test global treatment when no flag-specific treatments exist
+	configGlobalOnly := &FallbackTreatmentConfig{
+		GlobalFallbackTreatment: &FallbackTreatment{
+			Treatment: &globalTreatment,
+			Config:    nil,
+		},
+	}
+	calcGlobalOnly := NewFallbackTreatmentCalculatorImp(configGlobalOnly)
+	result = calcGlobalOnly.Resolve("any_flag", &label)
+	assert.Equal(t, "global_treatment", *result.Treatment)
+	assert.Nil(t, result.Config)
+	assert.Equal(t, "fallback - some_label", *result.label)
+}

engine/engine.go

@@ -4,10 +4,10 @@ import (
 	"fmt"
 	"math"
 
-	"github.com/splitio/go-split-commons/v8/engine/evaluator/impressionlabels"
-	"github.com/splitio/go-split-commons/v8/engine/grammar"
-	"github.com/splitio/go-split-commons/v8/engine/grammar/constants"
-	"github.com/splitio/go-split-commons/v8/engine/hash"
+	"github.com/splitio/go-split-commons/v9/engine/evaluator/impressionlabels"
+	"github.com/splitio/go-split-commons/v9/engine/grammar"
+	"github.com/splitio/go-split-commons/v9/engine/grammar/constants"
+	"github.com/splitio/go-split-commons/v9/engine/hash"
 
 	"github.com/splitio/go-toolkit/v5/hasher"
 	"github.com/splitio/go-toolkit/v5/logging"

engine/engine_test.go

@@ -7,10 +7,10 @@ import (
 	"os"
 	"testing"
 
-	"github.com/splitio/go-split-commons/v8/dtos"
-	"github.com/splitio/go-split-commons/v8/engine/grammar"
-	"github.com/splitio/go-split-commons/v8/engine/grammar/constants"
-	"github.com/splitio/go-split-commons/v8/engine/hash"
+	"github.com/splitio/go-split-commons/v9/dtos"
+	"github.com/splitio/go-split-commons/v9/engine/grammar"
+	"github.com/splitio/go-split-commons/v9/engine/grammar/constants"
+	"github.com/splitio/go-split-commons/v9/engine/hash"
 
 	"github.com/splitio/go-toolkit/v5/hasher"
 	"github.com/splitio/go-toolkit/v5/logging"

engine/evaluator/evaluator.go

@@ -4,11 +4,11 @@ import (
 	"fmt"
 	"time"
 
-	"github.com/splitio/go-split-commons/v8/dtos"
-	"github.com/splitio/go-split-commons/v8/engine"
-	"github.com/splitio/go-split-commons/v8/engine/evaluator/impressionlabels"
-	"github.com/splitio/go-split-commons/v8/engine/grammar"
-	"github.com/splitio/go-split-commons/v8/storage"
+	"github.com/splitio/go-split-commons/v9/dtos"
+	"github.com/splitio/go-split-commons/v9/engine"
+	"github.com/splitio/go-split-commons/v9/engine/evaluator/impressionlabels"
+	"github.com/splitio/go-split-commons/v9/engine/grammar"
+	"github.com/splitio/go-split-commons/v9/storage"
 
 	"github.com/splitio/go-toolkit/v5/logging"
 )
@@ -37,10 +37,11 @@ type Results struct {
 
 // Evaluator struct is the main evaluator
 type Evaluator struct {
-	splitStorage storage.SplitStorageConsumer
-	eng          *engine.Engine
-	logger       logging.LoggerInterface
-	ruleBuilder  grammar.RuleBuilder
+	splitStorage               storage.SplitStorageConsumer
+	eng                        *engine.Engine
+	logger                     logging.LoggerInterface
+	ruleBuilder                grammar.RuleBuilder
+	fallbackTratmentCalculator dtos.FallbackTreatmentCalculator
 }
 
 // NewEvaluator instantiates an Evaluator struct and returns a reference to it
@@ -53,21 +54,25 @@ func NewEvaluator(
 	logger logging.LoggerInterface,
 	featureFlagRules []string,
 	ruleBasedSegmentRules []string,
+	fallbackTreatmentCalculator dtos.FallbackTreatmentCalculator,
 ) *Evaluator {
 	e := &Evaluator{
-		splitStorage: splitStorage,
-		eng:          eng,
-		logger:       logger,
+		splitStorage:               splitStorage,
+		eng:                        eng,
+		logger:                     logger,
+		fallbackTratmentCalculator: fallbackTreatmentCalculator,
 	}
 	e.ruleBuilder = grammar.NewRuleBuilder(segmentStorage, ruleBasedSegmentStorage, largeSegmentStorage, featureFlagRules, ruleBasedSegmentRules, logger, e)
 	return e
 }
 
 func (e *Evaluator) evaluateTreatment(key string, bucketingKey string, featureFlag string, splitDto *dtos.SplitDTO, attributes map[string]interface{}) *Result {
 	var config *string
+	label := impressionlabels.SplitNotFound
 	if splitDto == nil {
-		e.logger.Warning(fmt.Sprintf("Feature flag %s not found, returning control.", featureFlag))
-		return &Result{Treatment: Control, Label: impressionlabels.SplitNotFound, Config: config}
+		fallbackTratment := e.fallbackTratmentCalculator.Resolve(featureFlag, &label)
+		e.logger.Warning(fmt.Sprintf("Feature flag %s not found, returning fallback treatment.", featureFlag))
+		return &Result{Treatment: *fallbackTratment.Treatment, Label: *fallbackTratment.Label(), Config: fallbackTratment.Config}
 	}
 
 	split := grammar.NewSplit(splitDto, e.logger, e.ruleBuilder)
@@ -113,6 +118,15 @@ func (e *Evaluator) evaluateTreatment(key string, bucketingKey string, featureFl
 		label = impressionlabels.NoConditionMatched
 	}
 
+	if *treatment == Control {
+		fallbackTreatment := e.fallbackTratmentCalculator.Resolve(featureFlag, &label)
+		return &Result{
+			Treatment: *fallbackTreatment.Treatment,
+			Label:     *fallbackTreatment.Label(),
+			Config:    fallbackTreatment.Config,
+		}
+	}
+
 	if _, ok := split.Configurations()[*treatment]; ok {
 		treatmentConfig := split.Configurations()[*treatment]
 		config = &treatmentConfig