Merge pull request #2459 from bugsnag/PLAT-13690-feature-flag-delegate

Convert @bugsnag/core/src/lib/feature-flag-delegate to TypeScript

Author: gingerbenw

packages/core/package.json

@@ -13,8 +13,7 @@
     "./lib/es-utils/includes": "./src/lib/es-utils/includes.js",
     "./lib/derecursify": "./src/lib/derecursify.js",
     "./lib/callback-runner": "./src/lib/callback-runner.js",
-    "./lib/path-normalizer": "./src/lib/path-normalizer.js",
-    "./lib/feature-flag-delegate": "./src/lib/feature-flag-delegate.js"
+    "./lib/path-normalizer": "./src/lib/path-normalizer.js"
   },
   "description": "Core classes and utilities for Bugsnag notifiers",
   "homepage": "https://www.bugsnag.com/",

packages/core/src/client.ts

@@ -8,7 +8,7 @@ import runCallbacks from './lib/callback-runner'
 import metadataDelegate from './lib/metadata-delegate'
 import runSyncCallbacks from './lib/sync-callback-runner'
 import BREADCRUMB_TYPES from './lib/breadcrumb-types'
-import { add, clear, merge } from './lib/feature-flag-delegate'
+import featureFlagDelegate from './lib/feature-flag-delegate'
 import { BreadcrumbType, Config, Delivery, FeatureFlag, LoggerConfig, NotifiableError, Notifier, OnBreadcrumbCallback, OnErrorCallback, OnSessionCallback, Plugin, SessionDelegate, User } from './common'
 
 const HUB_PREFIX = '00000'
@@ -127,15 +127,15 @@ export default class Client<T extends Config = Config> {
   }
 
   addFeatureFlag (name: string, variant: string | null = null) {
-    add(this._features, this._featuresIndex, name, variant)
+    featureFlagDelegate.add(this._features, this._featuresIndex, name, variant)
   }
 
   addFeatureFlags (featureFlags: FeatureFlag[]) {
-    merge(this._features, featureFlags, this._featuresIndex)
+    featureFlagDelegate.merge(this._features, featureFlags, this._featuresIndex)
   }
 
   clearFeatureFlag (name: string) {
-    clear(this._features, this._featuresIndex, name)
+    featureFlagDelegate.clear(this._features, this._featuresIndex, name)
   }
 
   clearFeatureFlags () {
@@ -205,7 +205,7 @@ export default class Client<T extends Config = Config> {
 
     // update and elevate some options
     this._metadata = assign({}, config.metadata)
-    merge(this._features, config.featureFlags, this._featuresIndex)
+    featureFlagDelegate.merge(this._features, config.featureFlags, this._featuresIndex)
     this._user = assign({}, config.user)
     this._context = config.context
     if (config.logger) this._logger = config.logger
@@ -351,7 +351,7 @@ export default class Client<T extends Config = Config> {
     event._metadata = assign({}, event._metadata, this._metadata)
     event._user = assign({}, event._user, this._user)
     event.breadcrumbs = this._breadcrumbs.slice()
-    merge(event._features, this._features, event._featuresIndex)
+    featureFlagDelegate.merge(event._features, this._features, event._featuresIndex)
 
     // exit early if events should not be sent on the current releaseStage
     if (this._config.enabledReleaseStages !== null && !includes(this._config.enabledReleaseStages, this._config.releaseStage)) {

packages/core/src/event.ts

@@ -33,7 +33,7 @@ export default class Event {
   public threads: Thread[]
 
   public _metadata: { [key: string]: any }
-  public _features: FeatureFlag | null[]
+  public _features: (FeatureFlag | null)[]
   public _featuresIndex: { [key: string]: number }
 
   public _user: User

packages/core/src/index.ts

@@ -12,6 +12,7 @@ export { default as listOfFunctions } from './lib/validators/list-of-functions'
 export { default as stringWithLength } from './lib/validators/string-with-length'
 export { default as metadataDelegate } from './lib/metadata-delegate'
 export { default as nodeFallbackStack } from './lib/node-fallback-stack'
+export { default as featureFlagDelegate } from './lib/feature-flag-delegate'
 export { default as runSyncCallbacks } from './lib/sync-callback-runner'
 
 export * from './common'

packages/core/src/lib/feature-flag-delegate.js

@@ -0,0 +1,88 @@
+import isArray from './es-utils/is-array'
+import jsonStringify from '@bugsnag/safe-json-stringify'
+import {FeatureFlag} from "../common";
+
+type FeatureFlagEventApi = {
+  featureFlag: string
+  variant?: string
+}
+
+interface FeatureFlagDelegate{
+  add: (existingFeatures: Array<FeatureFlag | null>, existingFeatureKeys: { [key: string]: number }, name?: string | null, variant?: any ) => void
+  merge: (
+    existingFeatures: Array<{ name: string; variant?: any } | null>,
+    newFeatures: any,
+    existingFeatureKeys: { [key: string]: any }
+  ) => Array<{ name: string; variant: any }> | undefined
+  toEventApi: (featureFlags: Array<FeatureFlag | null>) => FeatureFlagEventApi[]
+  clear: (features: (FeatureFlag | null)[], featuresIndex: { [key: string]: number }, name: string) => void
+}
+
+const featureFlagDelegate: FeatureFlagDelegate = {
+  add: (existingFeatures, existingFeatureKeys, name, variant) => {
+    if (typeof name !== 'string') {
+      return
+    }
+
+    if (variant === undefined) {
+      variant = null
+    } else if (variant !== null && typeof variant !== 'string') {
+      variant = jsonStringify(variant)
+    }
+
+    const existingIndex = existingFeatureKeys[name]
+    if (typeof existingIndex === 'number') {
+      existingFeatures[existingIndex] = {name, variant}
+      return
+    }
+
+    existingFeatures.push({name, variant})
+    existingFeatureKeys[name] = existingFeatures.length - 1
+  },
+
+  merge: (existingFeatures, newFeatures, existingFeatureKeys) => {
+    if (!isArray(newFeatures)) {
+      return
+    }
+
+    for (let i = 0; i < newFeatures.length; ++i) {
+      const feature = newFeatures[i]
+
+      if (feature === null || typeof feature !== 'object') {
+        continue
+      }
+
+      // 'add' will handle if 'name' doesn't exist & 'variant' is optional
+      featureFlagDelegate.add(existingFeatures, existingFeatureKeys, feature.name, feature.variant)
+    }
+
+    // Remove any nulls from the array to match the return type
+    return existingFeatures.filter(f => f) as Array<{ name: string; variant: any }>
+  },
+
+// convert feature flags from a map of 'name -> variant' into the format required
+// by the Bugsnag Event API:
+//   [{ featureFlag: 'name', variant: 'variant' }, { featureFlag: 'name 2' }]
+  toEventApi: (featureFlags) => {
+    return (featureFlags || [])
+      .filter((flag): flag is FeatureFlag => flag !== null && typeof flag === 'object')
+      .map((flag) => {
+        const result: FeatureFlagEventApi = { featureFlag: flag.name };
+        if (typeof flag.variant === 'string') {
+          result.variant = flag.variant;
+        }
+        return result;
+      });
+  },
+  
+  clear: (features, featuresIndex, name) => {
+    const existingIndex = featuresIndex[name]
+    if (typeof existingIndex === 'number') {
+      features[existingIndex] = null
+      // eslint-disable-next-line @typescript-eslint/no-dynamic-delete
+      delete featuresIndex[name]
+    }
+  }
+}
+
+export default featureFlagDelegate

packages/core/src/lib/feature-flag-delegate.ts

@@ -1,12 +1,12 @@
-import delegate from '../../src/lib/feature-flag-delegate'
+import featureFlagDelegate from '../../src/lib/feature-flag-delegate'
 
-describe('feature flag delegate', () => {
+describe('feature flag featureFlagDelegate', () => {
   describe('#add', () => {
     it('should do nothing if name is not passed', () => {
       const existingFeatures = [{ name: 'abc', variant: 'xyz' }]
       const existingFeaturesIndex = { abc: 0 }
 
-      delegate.add(existingFeatures, existingFeaturesIndex)
+      featureFlagDelegate.add(existingFeatures, existingFeaturesIndex)
 
       expect(existingFeatures).toStrictEqual([{ name: 'abc', variant: 'xyz' }])
       expect(existingFeaturesIndex).toStrictEqual({ abc: 0 })
@@ -16,7 +16,7 @@ describe('feature flag delegate', () => {
       const existingFeatures = [{ name: 'abc', variant: 'xyz' }]
       const existingFeaturesIndex = { abc: 0 }
 
-      delegate.add(existingFeatures, existingFeaturesIndex, undefined, '???')
+      featureFlagDelegate.add(existingFeatures, existingFeaturesIndex, undefined, '???')
 
       expect(existingFeatures).toStrictEqual([{ name: 'abc', variant: 'xyz' }])
       expect(existingFeaturesIndex).toStrictEqual({ abc: 0 })
@@ -26,7 +26,7 @@ describe('feature flag delegate', () => {
       const existingFeatures = [{ name: 'abc', variant: 'xyz' }]
       const existingFeaturesIndex = { abc: 0 }
 
-      delegate.add(existingFeatures, existingFeaturesIndex, null, '???')
+      featureFlagDelegate.add(existingFeatures, existingFeaturesIndex, null, '???')
 
       expect(existingFeatures).toStrictEqual([{ name: 'abc', variant: 'xyz' }])
       expect(existingFeaturesIndex).toStrictEqual({ abc: 0 })
@@ -36,7 +36,7 @@ describe('feature flag delegate', () => {
       const existingFeatures: any[] = []
       const existingFeaturesIndex = {}
 
-      delegate.add(existingFeatures, existingFeaturesIndex, 'good_feature')
+      featureFlagDelegate.add(existingFeatures, existingFeaturesIndex, 'good_feature')
 
       expect(existingFeatures).toStrictEqual([{ name: 'good_feature', variant: null }])
       expect(existingFeaturesIndex).toStrictEqual({ good_feature: 0 })
@@ -46,7 +46,7 @@ describe('feature flag delegate', () => {
       const existingFeatures: [] = []
       const existingFeaturesIndex = {}
 
-      delegate.add(existingFeatures, existingFeaturesIndex, 'ok_feature', null)
+      featureFlagDelegate.add(existingFeatures, existingFeaturesIndex, 'ok_feature', null)
 
       expect(existingFeatures).toStrictEqual([{ name: 'ok_feature', variant: null }])
       expect(existingFeaturesIndex).toStrictEqual({ ok_feature: 0 })
@@ -56,7 +56,7 @@ describe('feature flag delegate', () => {
       const existingFeatures: any[] = []
       const existingFeaturesIndex = {}
 
-      delegate.add(existingFeatures, existingFeaturesIndex, 'cool_feature', 'very ant')
+      featureFlagDelegate.add(existingFeatures, existingFeaturesIndex, 'cool_feature', 'very ant')
 
       expect(existingFeatures).toStrictEqual([{ name: 'cool_feature', variant: 'very ant' }])
       expect(existingFeaturesIndex).toStrictEqual({ cool_feature: 0 })
@@ -75,7 +75,7 @@ describe('feature flag delegate', () => {
       const existingFeatures: any[] = []
       const existingFeaturesIndex = {}
 
-      delegate.add(existingFeatures, existingFeaturesIndex, 'some_feature', variant)
+      featureFlagDelegate.add(existingFeatures, existingFeaturesIndex, 'some_feature', variant)
 
       expect(existingFeatures).toStrictEqual([{ name: 'some_feature', variant: expected }])
       expect(existingFeaturesIndex).toStrictEqual({ some_feature: 0 })
@@ -85,9 +85,9 @@ describe('feature flag delegate', () => {
       const existingFeatures = [{ name: 'a', variant: 'a' }, { name: 'b', variant: 'b' }, { name: 'c', variant: 'c' }, { name: 'd', variant: 'd' }, { name: 'e', variant: 'e' }]
       const existingFeaturesIndex = { a: 0, b: 1, c: 2, d: 3, e: 4 }
 
-      delegate.add(existingFeatures, existingFeaturesIndex, 'b', 'x')
-      delegate.add(existingFeatures, existingFeaturesIndex, 'e', 'y')
-      delegate.add(existingFeatures, existingFeaturesIndex, 'a', 'z')
+      featureFlagDelegate.add(existingFeatures, existingFeaturesIndex, 'b', 'x')
+      featureFlagDelegate.add(existingFeatures, existingFeaturesIndex, 'e', 'y')
+      featureFlagDelegate.add(existingFeatures, existingFeaturesIndex, 'a', 'z')
 
       expect(existingFeatures).toStrictEqual([{ name: 'a', variant: 'z' }, { name: 'b', variant: 'x' }, { name: 'c', variant: 'c' }, { name: 'd', variant: 'd' }, { name: 'e', variant: 'y' }])
       expect(existingFeaturesIndex).toStrictEqual({ a: 0, b: 1, c: 2, d: 3, e: 4 })
@@ -99,7 +99,7 @@ describe('feature flag delegate', () => {
       const existingFeatures: any[] = []
       const existingFeaturesIndex = {}
 
-      delegate.merge(existingFeatures, [
+      featureFlagDelegate.merge(existingFeatures, [
         { name: 'a', variant: 'b' },
         { name: 'c', variant: 'd' }
       ], existingFeaturesIndex)
@@ -112,7 +112,7 @@ describe('feature flag delegate', () => {
       const existingFeatures = [{ name: 'a', variant: 'a' }, { name: 'b', variant: 'b' }, { name: 'c', variant: 'c' }, { name: 'd', variant: 'd' }, { name: 'e', variant: 'e' }]
       const existingFeaturesIndex = { a: 0, b: 1, c: 2, d: 3, e: 4 }
 
-      delegate.merge(existingFeatures, [
+      featureFlagDelegate.merge(existingFeatures, [
         { name: 'b', variant: 'x' },
         { name: 'e', variant: 'y' },
         { name: 'a', variant: 'z' }
@@ -143,7 +143,7 @@ describe('feature flag delegate', () => {
         { name: 'p', variant: 'p' }
       ]
 
-      delegate.merge(existingFeatures, [
+      featureFlagDelegate.merge(existingFeatures, [
         { name: 'a', variant: 12345 },
         { name: 'c', variant: 0 },
         { name: 'e', variant: true },
@@ -183,7 +183,7 @@ describe('feature flag delegate', () => {
       const existingFeatures = [{ name: 'a', variant: 'a' }, { name: 'b', variant: 'b' }, { name: 'c', variant: 'c' }, { name: 'd', variant: 'd' }, { name: 'e', variant: 'e' }]
       const existingFeaturesIndex = { a: 0, b: 1, c: 2, d: 3, e: 3 }
 
-      delegate.merge(existingFeatures, [
+      featureFlagDelegate.merge(existingFeatures, [
         { name: 'b', variant: 'x' },
         { variant: 'y' },
         { name: 'a', variant: 'z' },
@@ -200,7 +200,7 @@ describe('feature flag delegate', () => {
       const existingFeatures = [{ name: 'a', variant: 'a' }, { name: 'b', variant: 'b' }, { name: 'c', variant: 'c' }, { name: 'd', variant: 'd' }, { name: 'e', variant: 'e' }]
       const existingFeaturesIndex = { a: 'a', b: 'b', c: 'c', d: 'd', e: 'e' }
 
-      delegate.merge(existingFeatures, { a: 'a', b: 'b', c: 'c' }, existingFeaturesIndex)
+      featureFlagDelegate.merge(existingFeatures, { a: 'a', b: 'b', c: 'c' }, existingFeaturesIndex)
 
       expect(existingFeatures).toStrictEqual([{ name: 'a', variant: 'a' }, { name: 'b', variant: 'b' }, { name: 'c', variant: 'c' }, { name: 'd', variant: 'd' }, { name: 'e', variant: 'e' }])
       expect(existingFeaturesIndex).toStrictEqual({ a: 'a', b: 'b', c: 'c', d: 'd', e: 'e' })
@@ -210,7 +210,7 @@ describe('feature flag delegate', () => {
       const features = [{ name: 'a', variant: 'a' }, { name: 'b', variant: 'b' }, { name: 'c', variant: 'c' }, { name: 'd', variant: 'd' }, { name: 'e', variant: 'e' }]
       const featuresIndex = { a: 0, b: 1, c: 2, d: 3, e: 4 }
 
-      delegate.merge(features, [
+      featureFlagDelegate.merge(features, [
         { name: 'b', variant: 'x' },
         'name: yes',
         undefined,
@@ -230,16 +230,16 @@ describe('feature flag delegate', () => {
       const features: any[] = []
       const featuresIndex = {}
 
-      delegate.add(features, featuresIndex, 'a', 'b')
-      delegate.merge(features, [
+      featureFlagDelegate.add(features, featuresIndex, 'a', 'b')
+      featureFlagDelegate.merge(features, [
         { name: 'c', variant: 'd' },
         { name: 'e' },
         { name: 'f', variant: 'g' }
       ], featuresIndex)
 
       expect(features).toStrictEqual([{ name: 'a', variant: 'b' }, { name: 'c', variant: 'd' }, { name: 'e', variant: null }, { name: 'f', variant: 'g' }])
 
-      expect(delegate.toEventApi(features)).toStrictEqual([
+      expect(featureFlagDelegate.toEventApi(features)).toStrictEqual([
         { featureFlag: 'a', variant: 'b' },
         { featureFlag: 'c', variant: 'd' },
         { featureFlag: 'e' },
@@ -248,7 +248,7 @@ describe('feature flag delegate', () => {
     })
 
     it('should handle an empty array', () => {
-      expect(delegate.toEventApi([])).toStrictEqual([])
+      expect(featureFlagDelegate.toEventApi([])).toStrictEqual([])
     })
   })
 })