feat: Added GetDetailedFeatureDecisionUnsafe (#266)

Summary:

Temporary changes in go-sdk for adding a new method GetDetailedFeatureDecisionUnsafe
This is added to support some agent features. Which will be removed later on.

Testplan:

All FSC should be passed. 

Co-authored-by: Yasir Ali <yali@folio3.com>
Co-authored-by: yasirfolio3 <39988750+yasirfolio3@users.noreply.github.com>

Author: msohailhussain

pkg/client/client.go

@@ -1,5 +1,5 @@
 /****************************************************************************
- * Copyright 2019, Optimizely, Inc. and contributors                        *
+ * Copyright 2019-2020, Optimizely, Inc. and contributors                   *
  *                                                                          *
  * Licensed under the Apache License, Version 2.0 (the "License");          *
  * you may not use this file except in compliance with the License.         *
@@ -430,29 +430,9 @@ func (o *OptimizelyClient) GetAllFeatureVariablesWithDecision(featureKey string,
 			}
 		}
 
-		var out interface{}
-		out = val
-		switch varType := v.Type; varType {
-		case entities.Boolean:
-			out, err = strconv.ParseBool(val)
-			errs = multierror.Append(errs, err)
-		case entities.Double:
-			out, err = strconv.ParseFloat(val, 64)
-			errs = multierror.Append(errs, err)
-		case entities.Integer:
-			out, err = strconv.Atoi(val)
-			errs = multierror.Append(errs, err)
-		case entities.JSON:
-			var optlyJSON *optimizelyjson.OptimizelyJSON
-			optlyJSON, err = optimizelyjson.NewOptimizelyJSONfromString(val)
-			out = optlyJSON.ToMap()
-			errs = multierror.Append(errs, err)
-		case entities.String:
-		default:
-			o.logger.Warning(fmt.Sprintf(`type "%s" is unknown, returning string`, varType))
-		}
-
-		variableMap[v.Key] = out
+		typedValue, typedError := o.getTypedValue(val, v.Type)
+		errs = multierror.Append(errs, typedError)
+		variableMap[v.Key] = typedValue
 	}
 
 	if o.notificationCenter != nil {
@@ -467,6 +447,70 @@ func (o *OptimizelyClient) GetAllFeatureVariablesWithDecision(featureKey string,
 	return enabled, variableMap, errs.ErrorOrNil()
 }
 
+// GetDetailedFeatureDecisionUnsafe triggers an impression event and returns all the variables
+// for a given feature along with the experiment key, variation key and the enabled state.
+// Usage of this method is unsafe and not recommended since it can be removed in any of the next releases.
+func (o *OptimizelyClient) GetDetailedFeatureDecisionUnsafe(featureKey string, userContext entities.UserContext, disableTracking bool) (decisionInfo decision.UnsafeFeatureDecisionInfo, err error) {
+
+	decisionInfo = decision.UnsafeFeatureDecisionInfo{}
+	decisionInfo.VariableMap = make(map[string]interface{})
+	decisionContext, featureDecision, err := o.getFeatureDecision(featureKey, "", userContext)
+	if err != nil {
+		o.logger.Error("Optimizely SDK tracking error", err)
+		return decisionInfo, err
+	}
+
+	if featureDecision.Variation != nil {
+		decisionInfo.Enabled = featureDecision.Variation.FeatureEnabled
+
+		if featureDecision.Source == decision.FeatureTest {
+			decisionInfo.VariationKey = featureDecision.Variation.Key
+			decisionInfo.ExperimentKey = featureDecision.Experiment.Key
+			// Triggers impression events when applicable
+			if !disableTracking {
+				// send impression event for feature tests
+				impressionEvent := event.CreateImpressionUserEvent(decisionContext.ProjectConfig, featureDecision.Experiment, *featureDecision.Variation, userContext)
+				o.EventProcessor.ProcessEvent(impressionEvent)
+			}
+		}
+	}
+
+	feature := decisionContext.Feature
+	if feature == nil {
+		o.logger.Warning(fmt.Sprintf(`feature "%s" does not exist`, featureKey))
+		return decisionInfo, nil
+	}
+
+	errs := new(multierror.Error)
+
+	for _, v := range feature.VariableMap {
+		val := v.DefaultValue
+
+		if decisionInfo.Enabled {
+			if variable, ok := featureDecision.Variation.Variables[v.ID]; ok {
+				val = variable.Value
+			} else {
+				o.logger.Warning(fmt.Sprintf(`variable with id "%s" does not exist`, v.ID))
+			}
+		}
+
+		typedValue, typedError := o.getTypedValue(val, v.Type)
+		errs = multierror.Append(errs, typedError)
+		decisionInfo.VariableMap[v.Key] = typedValue
+	}
+
+	if o.notificationCenter != nil {
+		decisionNotification := decision.FeatureNotificationWithVariables(featureKey, &featureDecision, &userContext,
+			map[string]interface{}{"variableValues": decisionInfo.VariableMap})
+		decisionNotification.Type = notification.AllFeatureVariables
+
+		if err = o.notificationCenter.Send(notification.Decision, *decisionNotification); err != nil {
+			o.logger.Warning(fmt.Sprintf("Problem with sending notification: %v", err))
+		}
+	}
+	return decisionInfo, errs.ErrorOrNil()
+}
+
 // GetAllFeatureVariables returns all the variables as OptimizelyJSON object for a given feature.
 func (o *OptimizelyClient) GetAllFeatureVariables(featureKey string, userContext entities.UserContext) (optlyJSON *optimizelyjson.OptimizelyJSON, err error) {
 	_, variableMap, err := o.GetAllFeatureVariablesWithDecision(featureKey, userContext)
@@ -685,6 +729,26 @@ func (o *OptimizelyClient) RemoveOnTrack(id int) error {
 	return nil
 }
 
+func (o *OptimizelyClient) getTypedValue(value string, variableType entities.VariableType) (convertedValue interface{}, err error) {
+	convertedValue = value
+	switch variableType {
+	case entities.Boolean:
+		convertedValue, err = strconv.ParseBool(value)
+	case entities.Double:
+		convertedValue, err = strconv.ParseFloat(value, 64)
+	case entities.Integer:
+		convertedValue, err = strconv.Atoi(value)
+	case entities.JSON:
+		var optlyJSON *optimizelyjson.OptimizelyJSON
+		optlyJSON, err = optimizelyjson.NewOptimizelyJSONfromString(value)
+		convertedValue = optlyJSON.ToMap()
+	case entities.String:
+	default:
+		o.logger.Warning(fmt.Sprintf(`type "%s" is unknown, returning string`, variableType))
+	}
+	return convertedValue, err
+}
+
 func (o *OptimizelyClient) getProjectConfig() (projectConfig config.ProjectConfig, err error) {
 
 	if isNil(o.ConfigManager) {