From 51e601b63bb81fa3eef125a60e694da13dedc67f Mon Sep 17 00:00:00 2001
From: Tymoteusz Czech <2625371+Tymek@users.noreply.github.com>
Date: Thu, 9 Nov 2023 12:57:31 +0100
Subject: [PATCH] feat: variant feature status - client specification update

---
 package.json                           |   2 +-
 src/client.ts                          |  61 ++++++++---------
 src/index.ts                           |   6 +-
 src/test/client.test.ts                |   8 +--
 src/test/snapshots/client.test.ts.md   |  18 ++---
 src/test/snapshots/client.test.ts.snap | Bin 372 -> 373 bytes
 src/test/snapshots/index.test.ts.md    |   1 +
 src/test/snapshots/index.test.ts.snap  | Bin 222 -> 234 bytes
 src/unleash.ts                         |  91 +++++++++++++------------
 src/variant.ts                         |  22 +++---
 yarn.lock                              |   8 +--
 11 files changed, 108 insertions(+), 109 deletions(-)

diff --git a/package.json b/package.json
index 6d8c78e8..9a0f2d9b 100644
--- a/package.json
+++ b/package.json
@@ -56,7 +56,7 @@
     "@types/sinon": "^10.0.15",
     "@typescript-eslint/eslint-plugin": "^6.0.0",
     "@typescript-eslint/parser": "^6.0.0",
-    "@unleash/client-specification": "^5.0.2",
+    "@unleash/client-specification": "^5.1.0",
     "ava": "^5.3.0",
     "coveralls": "^3.1.1",
     "cross-env": "^7.0.3",
diff --git a/src/client.ts b/src/client.ts
index 59c7705b..cbc28a38 100644
--- a/src/client.ts
+++ b/src/client.ts
@@ -2,10 +2,7 @@ import { EventEmitter } from 'events';
 import { Strategy, StrategyTransportInterface } from './strategy';
 import { FeatureInterface } from './feature';
 import { RepositoryInterface } from './repository';
-import {
-  Variant, VariantDefinition,
-  getDefaultVariant, selectVariant, VariantWithFeatureStatus,
-} from './variant';
+import { Variant, VariantDefinition, defaultVariant, selectVariant } from './variant';
 import { Context } from './context';
 import { Constraint, Segment, StrategyResult } from './strategy/strategy';
 import { createImpressionEvent, UnleashEvents } from './events';
@@ -46,9 +43,11 @@ export default class UnleashClient extends EventEmitter {
     return this.strategies.find((strategy: Strategy): boolean => strategy.name === name);
   }
 
-  warnStrategyOnce(missingStrategy: string,
-                   name: string,
-                   strategies: StrategyTransportInterface[]) {
+  warnStrategyOnce(
+    missingStrategy: string,
+    name: string,
+    strategies: StrategyTransportInterface[],
+  ) {
     if (!this.warnedStrategies[missingStrategy + name]) {
       this.warnedStrategies[missingStrategy + name] = true;
       this.emit(
@@ -75,7 +74,7 @@ export default class UnleashClient extends EventEmitter {
       return true;
     }
 
-    return feature.dependencies.every(parent => {
+    return feature.dependencies.every((parent) => {
       const parentToggle = this.repository.getToggle(parent.feature);
 
       if (!parentToggle) {
@@ -88,7 +87,10 @@ export default class UnleashClient extends EventEmitter {
 
       if (parent.enabled !== false) {
         if (parent.variants?.length) {
-          const {name, featureEnabled} = this.getVariant(parent.feature, context);
+          const { name, feature_enabled: featureEnabled } = this.getVariant(
+            parent.feature,
+            context,
+          );
           return featureEnabled && parent.variants.includes(name);
         }
         return this.isEnabled(parent.feature, context, () => false);
@@ -149,11 +151,12 @@ export default class UnleashClient extends EventEmitter {
         return false;
       }
       const constraints = this.yieldConstraintsFor(strategySelector);
-      const result =
-        strategy.getResult(strategySelector.parameters,
-          context,
-          constraints,
-          strategySelector.variants);
+      const result = strategy.getResult(
+        strategySelector.parameters,
+        context,
+        constraints,
+        strategySelector.variants,
+      );
 
       if (result.enabled) {
         strategyResult = result;
@@ -165,7 +168,7 @@ export default class UnleashClient extends EventEmitter {
     return strategyResult;
   }
 
-  * yieldConstraintsFor(
+  *yieldConstraintsFor(
     strategy: StrategyTransportInterface,
   ): IterableIterator<Constraint | undefined> {
     if (strategy.constraints) {
@@ -178,7 +181,7 @@ export default class UnleashClient extends EventEmitter {
     yield* this.yieldSegmentConstraints(segments);
   }
 
-  * yieldSegmentConstraints(
+  *yieldSegmentConstraints(
     segments: (Segment | undefined)[],
   ): IterableIterator<Constraint | undefined> {
     // eslint-disable-next-line no-restricted-syntax
@@ -194,7 +197,7 @@ export default class UnleashClient extends EventEmitter {
     }
   }
 
-  getVariant(name: string, context: Context, fallbackVariant?: Variant): VariantWithFeatureStatus {
+  getVariant(name: string, context: Context, fallbackVariant?: Variant): Variant {
     const feature = this.repository.getToggle(name);
     const variant = this.resolveVariant(feature, context, true, fallbackVariant);
     if (feature?.impressionData) {
@@ -215,9 +218,7 @@ export default class UnleashClient extends EventEmitter {
   // This function is intended to close an issue in the proxy where feature enabled
   // state gets checked twice when resolving a variant with random stickiness and
   // gradual rollout. This is not intended for general use, prefer getVariant instead
-  forceGetVariant(name: string,
-                  context: Context,
-                  fallbackVariant?: Variant): VariantWithFeatureStatus {
+  forceGetVariant(name: string, context: Context, fallbackVariant?: Variant): Variant {
     const feature = this.repository.getToggle(name);
     return this.resolveVariant(feature, context, true, fallbackVariant);
   }
@@ -227,11 +228,11 @@ export default class UnleashClient extends EventEmitter {
     context: Context,
     checkToggle: boolean,
     fallbackVariant?: Variant,
-  ): VariantWithFeatureStatus {
-    const fallback = fallbackVariant || getDefaultVariant();
+  ): Variant {
+    const fallback = fallbackVariant || defaultVariant;
 
     if (typeof feature === 'undefined') {
-      return { ...fallback, featureEnabled: false };
+      return { ...fallback, feature_enabled: false };
     }
 
     let featureEnabled = !checkToggle;
@@ -240,30 +241,28 @@ export default class UnleashClient extends EventEmitter {
       featureEnabled = result.enabled;
 
       if (result.enabled && result.variant) {
-        return { ...result.variant, featureEnabled };
+        return { ...result.variant, feature_enabled: featureEnabled };
       }
 
       if (!result.enabled) {
-        return { ...fallback, featureEnabled };
+        return { ...fallback, feature_enabled: featureEnabled };
       }
     }
 
-    if (!feature.variants ||
-      !Array.isArray(feature.variants) ||
-      feature.variants.length === 0) {
-      return { ...fallback, featureEnabled };
+    if (!feature.variants || !Array.isArray(feature.variants) || feature.variants.length === 0) {
+      return { ...fallback, feature_enabled: featureEnabled };
     }
 
     const variant: VariantDefinition | null = selectVariant(feature, context);
     if (variant === null) {
-      return { ...fallback, featureEnabled };
+      return { ...fallback, feature_enabled: featureEnabled };
     }
 
     return {
       name: variant.name,
       payload: variant.payload,
       enabled: true,
-      featureEnabled,
+      feature_enabled: featureEnabled,
     };
   }
 }
diff --git a/src/index.ts b/src/index.ts
index 0467824d..e21602b7 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -1,6 +1,6 @@
 import { once } from 'events';
 import { Unleash } from './unleash';
-import { Variant, getDefaultVariant, PayloadType } from './variant';
+import { Variant, defaultVariant, PayloadType } from './variant';
 import { Context } from './context';
 import { TagFilter } from './tags';
 import { UnleashEvents } from './events';
@@ -53,7 +53,7 @@ export function getVariant(
   context: Context = {},
   fallbackVariant?: Variant,
 ): Variant {
-  const variant = fallbackVariant || getDefaultVariant();
+  const variant = fallbackVariant || defaultVariant;
   return instance ? instance.getVariant(name, context, variant) : variant;
 }
 
@@ -62,7 +62,7 @@ export function forceGetVariant(
   context: Context = {},
   fallbackVariant?: Variant,
 ): Variant {
-  const variant = fallbackVariant || getDefaultVariant();
+  const variant = fallbackVariant || defaultVariant;
   return instance ? instance.forceGetVariant(name, context, variant) : variant;
 }
 
diff --git a/src/test/client.test.ts b/src/test/client.test.ts
index 426c44aa..0117d018 100644
--- a/src/test/client.test.ts
+++ b/src/test/client.test.ts
@@ -248,7 +248,7 @@ test('should always return defaultVariant if missing variant', (t) => {
   const defaultVariant = {
     enabled: false,
     name: 'disabled',
-    featureEnabled: true
+    feature_enabled: true
   };
   t.deepEqual(result, defaultVariant);
 
@@ -259,7 +259,7 @@ test('should always return defaultVariant if missing variant', (t) => {
       type: 'string',
       value: '',
     },
-    featureEnabled: true
+    feature_enabled: true
   };
   const result2 = client.getVariant('feature-but-no-variant', {}, fallback);
 
@@ -381,7 +381,7 @@ test('should favor strategy variant over feature variant', (t) => {
       name: 'strategyVariantName',
       payload: { type: 'string', value: 'strategyVariantValue' },
       enabled: true,
-      featureEnabled: true
+      feature_enabled: true
     },
   );
 });
@@ -411,7 +411,7 @@ test('should return disabled variant for non-matching strategy variant', (t) =>
   t.deepEqual(variant, {
       name: 'disabled',
       enabled: false,
-      featureEnabled: false,
+      feature_enabled: false,
     },
   );
 });
diff --git a/src/test/snapshots/client.test.ts.md b/src/test/snapshots/client.test.ts.md
index 15fa9ec8..67e13901 100644
--- a/src/test/snapshots/client.test.ts.md
+++ b/src/test/snapshots/client.test.ts.md
@@ -10,7 +10,7 @@ Generated by [AVA](https://avajs.dev).
 
     {
       enabled: true,
-      featureEnabled: true,
+      feature_enabled: true,
       name: 'variant3',
       payload: {
         type: 'string',
@@ -22,7 +22,7 @@ Generated by [AVA](https://avajs.dev).
 
     {
       enabled: true,
-      featureEnabled: true,
+      feature_enabled: true,
       name: 'variant3',
       payload: {
         type: 'string',
@@ -34,7 +34,7 @@ Generated by [AVA](https://avajs.dev).
 
     {
       enabled: true,
-      featureEnabled: true,
+      feature_enabled: true,
       name: 'variant3',
       payload: {
         type: 'string',
@@ -48,7 +48,7 @@ Generated by [AVA](https://avajs.dev).
 
     {
       enabled: true,
-      featureEnabled: true,
+      feature_enabled: true,
       name: 'variant3',
       payload: {
         type: 'string',
@@ -60,7 +60,7 @@ Generated by [AVA](https://avajs.dev).
 
     {
       enabled: true,
-      featureEnabled: true,
+      feature_enabled: true,
       name: 'variant1',
       payload: {
         type: 'string',
@@ -72,7 +72,7 @@ Generated by [AVA](https://avajs.dev).
 
     {
       enabled: true,
-      featureEnabled: true,
+      feature_enabled: true,
       name: 'variant3',
       payload: {
         type: 'string',
@@ -86,7 +86,7 @@ Generated by [AVA](https://avajs.dev).
 
     {
       enabled: true,
-      featureEnabled: true,
+      feature_enabled: true,
       name: 'variant3',
       payload: {
         type: 'string',
@@ -98,7 +98,7 @@ Generated by [AVA](https://avajs.dev).
 
     {
       enabled: true,
-      featureEnabled: true,
+      feature_enabled: true,
       name: 'variant3',
       payload: {
         type: 'string',
@@ -110,7 +110,7 @@ Generated by [AVA](https://avajs.dev).
 
     {
       enabled: true,
-      featureEnabled: true,
+      feature_enabled: true,
       name: 'variant2',
       payload: {
         type: 'string',
diff --git a/src/test/snapshots/client.test.ts.snap b/src/test/snapshots/client.test.ts.snap
index 8bf258394171363658de29db3b8dd16d3b9e122c..3c3968d8e54be3a8216f5344637b5f10a5eadddb 100644
GIT binary patch
literal 373
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zBm4o>S|5uD00000000B+RxwV)FckGq)3ggD6^Pjf$dEJ=LQLF%nFaLIxJ|$~A#qwd
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TrGVph2{`@&BtlhsCky}p(FCj!

literal 372
zcmV-)0gL`YRzV<BZeeh9Xm4~Nb~6eC0BFk(;rSjv{~@dke}e>N4IgLZpV4Pp-aS3O
zRfJOrnjeb@00000000B+R<TaQFc9@6P1=Pv6|nmQG9--z5)%tEGYgW_T$_M#O5(J1
z&X<&l-{60k_yVp~lOae*6$3$y?I-)>v+nuHdh%u#%5?gem#?T3E%C+6<Ft?w&rlbc
z;!BYwLTSE=QE_}Ogybts=CS6f;=W5g$(2~pA)S|-C=y!S!KKOiY};S}))mdygnL3s
zcq5#GJqG(We88y&sF#l8FgRh*V=$r|;|xp&))@MzL?|)Z#m1<yJDi~)u6XlPQcsB|
ztb)P*Rsn+{z&jDDD=oxYrXt!hH$Q0OlW-0V#>O|sMzfq=FY0o3uCqkV8!6UO$fC~a
zQ51Cgb^86Kew7CV2Y5gbxVzEWz|lTqzg_zI|4qNPy}!x^E)Mw$c%HjQ=LARV1f71r
S({Iu){U%?2Y8ycw3;+O)&aM9d

diff --git a/src/test/snapshots/index.test.ts.md b/src/test/snapshots/index.test.ts.md
index 11a74b24..680844d6 100644
--- a/src/test/snapshots/index.test.ts.md
+++ b/src/test/snapshots/index.test.ts.md
@@ -18,6 +18,7 @@ Generated by [AVA](https://avajs.dev).
 
     {
       enabled: false,
+      feature_enabled: false,
       name: 'disabled',
     }
 
diff --git a/src/test/snapshots/index.test.ts.snap b/src/test/snapshots/index.test.ts.snap
index e7521419ff49f6c8ecf303bb37c8f7412ced3ecd..50b8566647f91e6a849e0285659fb112e6cf2024 100644
GIT binary patch
literal 234
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literal 222
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Y9FCOCVz64Au0jz40KXpJA^rdW0GDx7#sB~S

diff --git a/src/unleash.ts b/src/unleash.ts
index 26d984b8..c5b6114a 100644
--- a/src/unleash.ts
+++ b/src/unleash.ts
@@ -7,7 +7,7 @@ import { Context } from './context';
 import { Strategy, defaultStrategies } from './strategy';
 
 import { FeatureInterface } from './feature';
-import { Variant, getDefaultVariant, VariantWithFeatureStatus } from './variant';
+import { Variant, defaultVariant } from './variant';
 import {
   FallbackFunction,
   createFallbackFunction,
@@ -48,30 +48,30 @@ export class Unleash extends EventEmitter {
   private ready: boolean = false;
 
   constructor({
-                appName,
-                environment = 'default',
-                projectName,
-                instanceId,
-                url,
-                refreshInterval = 15 * 1000,
-                metricsInterval = 60 * 1000,
-                metricsJitter = 0,
-                disableMetrics = false,
-                backupPath = BACKUP_PATH,
-                strategies = [],
-                repository,
-                namePrefix,
-                customHeaders,
-                customHeadersFunction,
-                timeout,
-                httpOptions,
-                tags,
-                bootstrap = {},
-                bootstrapOverride,
-                storageProvider,
-                disableAutoStart = false,
-                skipInstanceCountWarning = false,
-              }: UnleashConfig) {
+    appName,
+    environment = 'default',
+    projectName,
+    instanceId,
+    url,
+    refreshInterval = 15 * 1000,
+    metricsInterval = 60 * 1000,
+    metricsJitter = 0,
+    disableMetrics = false,
+    backupPath = BACKUP_PATH,
+    strategies = [],
+    repository,
+    namePrefix,
+    customHeaders,
+    customHeadersFunction,
+    timeout,
+    httpOptions,
+    tags,
+    bootstrap = {},
+    bootstrapOverride,
+    storageProvider,
+    disableAutoStart = false,
+    skipInstanceCountWarning = false,
+  }: UnleashConfig) {
     super();
 
     Unleash.instanceCount++;
@@ -278,47 +278,48 @@ export class Unleash extends EventEmitter {
 
   getVariant(name: string, context: Context = {}, fallbackVariant?: Variant): Variant {
     const enhancedContext = { ...this.staticContext, ...context };
-    let result: VariantWithFeatureStatus;
+    let variant: Variant;
     if (this.ready) {
-      result = this.client.getVariant(name, enhancedContext, fallbackVariant);
+      variant = this.client.getVariant(name, enhancedContext, fallbackVariant);
     } else {
-      result = typeof fallbackVariant !== 'undefined' ?
-        { ...fallbackVariant, featureEnabled: false } :
-        { ...getDefaultVariant(), featureEnabled: false };
+      variant =
+        typeof fallbackVariant !== 'undefined'
+          ? { ...fallbackVariant, feature_enabled: false }
+          : defaultVariant;
       this.emit(
         UnleashEvents.Warn,
-        `Unleash has not been initialized yet. isEnabled(${name}) defaulted to ${result}`,
+        `Unleash has not been initialized yet. isEnabled(${name}) defaulted to ${variant}`,
       );
     }
-    const { featureEnabled, ...variant } = result;
-    if (result.name) {
-      this.countVariant(name, result.name);
+
+    if (variant.name) {
+      this.countVariant(name, variant.name);
     }
 
-    this.count(name, Boolean(featureEnabled));
+    this.count(name, Boolean(variant.feature_enabled));
 
     return variant;
   }
 
   forceGetVariant(name: string, context: Context = {}, fallbackVariant?: Variant): Variant {
     const enhancedContext = { ...this.staticContext, ...context };
-    let result;
+    let variant: Variant;
     if (this.ready) {
-      result = this.client.forceGetVariant(name, enhancedContext, fallbackVariant);
+      variant = this.client.forceGetVariant(name, enhancedContext, fallbackVariant);
     } else {
-      result = typeof fallbackVariant !== 'undefined' ?
-        { ...fallbackVariant, featureEnabled: false } :
-        { ...getDefaultVariant(), featureEnabled: false };
+      variant =
+        typeof fallbackVariant !== 'undefined'
+          ? { ...fallbackVariant, feature_enabled: false }
+          : defaultVariant;
       this.emit(
         UnleashEvents.Warn,
-        `Unleash has not been initialized yet. isEnabled(${name}) defaulted to ${result}`,
+        `Unleash has not been initialized yet. isEnabled(${name}) defaulted to ${variant}`,
       );
     }
-    const { featureEnabled, ...variant } = result;
-    if (result.name) {
-      this.countVariant(name, result.name);
+    if (variant.name) {
+      this.countVariant(name, variant.name);
     }
-    this.count(name, featureEnabled);
+    this.count(name, variant.feature_enabled || false);
 
     return variant;
   }
diff --git a/src/variant.ts b/src/variant.ts
index a7292734..406ba7c0 100644
--- a/src/variant.ts
+++ b/src/variant.ts
@@ -32,18 +32,14 @@ export interface Variant {
   name: string;
   enabled: boolean;
   payload?: Payload;
+  feature_enabled?: boolean;
 }
 
-export interface VariantWithFeatureStatus extends Variant {
-  featureEnabled: boolean;
-}
-
-export function getDefaultVariant(): Variant {
-  return {
-    name: 'disabled',
-    enabled: false,
-  };
-}
+export const defaultVariant: Variant = {
+  name: 'disabled',
+  enabled: false,
+  feature_enabled: false,
+};
 
 function randomString() {
   return String(Math.round(Math.random() * 100000));
@@ -73,8 +69,10 @@ function overrideMatchesContext(context: Context): (o: Override) => boolean {
     o.values.some((value) => value === resolveContextValue(context, o.contextName));
 }
 
-function findOverride(variants: VariantDefinition[],
-                      context: Context): VariantDefinition | undefined {
+function findOverride(
+  variants: VariantDefinition[],
+  context: Context,
+): VariantDefinition | undefined {
   return variants
     .filter((variant) => variant.overrides)
     .find((variant) => variant.overrides?.some(overrideMatchesContext(context)));
diff --git a/yarn.lock b/yarn.lock
index e0420986..3b89d859 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -785,10 +785,10 @@
     "@typescript-eslint/types" "6.4.1"
     eslint-visitor-keys "^3.4.1"
 
-"@unleash/client-specification@^5.0.2":
-  version "5.0.2"
-  resolved "https://registry.yarnpkg.com/@unleash/client-specification/-/client-specification-5.0.2.tgz#810303f04baf6f547148c90cecbbe87dd5fb221e"
-  integrity sha512-KW/NEQFcjuuxoDDTyL9GcotJxntr4qQ1Kk+iHA/FrFMXpLHvulGNwPE9ojcwVRk02jNE+7hLW4q1B5JSblnTFA==
+"@unleash/client-specification@^5.1.0":
+  version "5.1.0"
+  resolved "https://registry.yarnpkg.com/@unleash/client-specification/-/client-specification-5.1.0.tgz#f95d76b085d857ab89830e5f3ba7ea5482254bd0"
+  integrity sha512-703U1Sw2hXg5MrVXXfEwAIWMinUxTfOHpbcjdjbTyxejaK0mjx4S8zBc5pffs/jlmwSct9eJuRNWnRvWGPQaxg==
 
 acorn-jsx@^5.3.2:
   version "5.3.2"