feat(ForcedDecisions): Add forced-decisions APIs to OptimizelyUserContext (#705)

Add a set of new APIs for forced-decisions to OptimizelyUserContext:

setForcedDecision
getForcedDecision
removeForcedDecision
removeAllForcedDecisions

Author: yavorona

packages/optimizely-sdk/lib/core/decision/index.tests.js

@@ -69,6 +69,23 @@ describe('lib/core/decision', function() {
     });
   });
 
+  describe('getVariationId method', function() {
+    it('should return null when variation is null', function() {
+      var variationId = decision.getVariationId(rolloutDecisionObj);
+      assert.strictEqual(variationId, null);
+    });
+
+    it('should return null when variation is not defined', function() {
+      var variationId = decision.getVariationId({});
+      assert.strictEqual(variationId, null);
+    });
+
+    it('should return variation id when variation is defined', function() {
+      var variationId = decision.getVariationId(featureTestDecisionObj);
+      assert.strictEqual(variationId, '594096');
+    });
+  });
+
   describe('getFeatureEnabledFromVariation method', function() {
     it('should return false when variation is null', function() {
       var featureEnabled = decision.getFeatureEnabledFromVariation(rolloutDecisionObj);

packages/optimizely-sdk/lib/core/decision/index.ts

@@ -22,7 +22,7 @@ import { DecisionObj } from '../decision_service';
  * @returns {string}                        Experiment key or empty string if experiment is null
  */
 export function getExperimentKey(decisionObj: DecisionObj): string {
-   return decisionObj.experiment?.key ?? '';
+  return decisionObj.experiment?.key ?? '';
 }
 
 /**
@@ -31,7 +31,7 @@ export function getExperimentKey(decisionObj: DecisionObj): string {
  * @returns {string}                        Variation key or empty string if variation is null
  */
 export function getVariationKey(decisionObj: DecisionObj): string {
-   return decisionObj.variation?.key ?? '';
+  return decisionObj.variation?.key ?? '';
 }
 
 /**
@@ -40,7 +40,7 @@ export function getVariationKey(decisionObj: DecisionObj): string {
  * @returns {boolean}                       featureEnabled boolean or false if variation is null
  */
 export function getFeatureEnabledFromVariation(decisionObj: DecisionObj): boolean {
-   return decisionObj.variation?.featureEnabled ?? false;
+  return decisionObj.variation?.featureEnabled ?? false;
 }
 
 /**
@@ -49,5 +49,14 @@ export function getFeatureEnabledFromVariation(decisionObj: DecisionObj): boolea
  * @returns {string}                        Experiment id or null if experiment is null
  */
 export function getExperimentId(decisionObj: DecisionObj): string | null {
-   return decisionObj.experiment?.id ?? null;
+  return decisionObj.experiment?.id ?? null;
+}
+
+/**
+ * Get variation id from the provided decision object
+ * @param   {DecisionObj} decisionObj       Object representing decision
+ * @returns {string}                        Variation id or null if variation is null
+ */
+export function getVariationId(decisionObj: DecisionObj): string | null {
+  return decisionObj.variation?.id ?? null;
 }