SDKS-5789. Add singleSync config parameter

src/types.ts

@@ -117,7 +117,8 @@ export interface ISettings {
     splitFilters: SplitIO.SplitFilter[],
     impressionsMode: SplitIO.ImpressionsMode,
     __splitFiltersValidation: ISplitFiltersValidation,
-    localhostMode?: SplitIO.LocalhostFactory
+    localhostMode?: SplitIO.LocalhostFactory,
+    singleSync: boolean
   },
   readonly runtime: {
     ip: string | false
@@ -214,6 +215,11 @@ interface ISharedSettings {
      * @default 'OPTIMIZED'
      */
     impressionsMode?: SplitIO.ImpressionsMode,
+    /**
+     * single Sync enables.
+     * @property {boolean} singleSync
+     */
+    singleSync: boolean
   }
 }
 /**

src/utils/settingsValidation/__tests__/index.spec.ts

@@ -40,6 +40,7 @@ describe('settingsValidation', () => {
       telemetry: 'https://telemetry.split.io/api',
     });
     expect(settings.sync.impressionsMode).toBe(OPTIMIZED);
+    expect(settings.sync.singleSync).toBe(false);
   });
 
   test('override with default impressionMode if provided one is invalid', () => {
@@ -163,6 +164,26 @@ describe('settingsValidation', () => {
     expect(settingsWithStreamingEnabled.streamingEnabled).toBe(true); // If streamingEnabled is not provided, it will be true.
   });
 
+  test('singleSync should be overwritable and false by default', () => {
+    const settingsWithSingleSyncDisabled = settingsValidation({
+      core: {
+        authorizationKey: 'dummy token',
+      }
+    }, minimalSettingsParams);
+    const settingsWithSingleSyncEnabled = settingsValidation({
+      core: {
+        authorizationKey: 'dummy token'
+      },
+      sync: {
+        singleSync: true
+      }
+    }, minimalSettingsParams);
+
+    expect(settingsWithSingleSyncDisabled.sync.singleSync).toBe(false); // If singleSync is not provided, it will be true.
+    expect(settingsWithSingleSyncEnabled.sync.singleSync).toBe(true); // When creating a setting instance, it will have the provided value for singleSync
+
+  });
+
   const storageMock = () => { };
   const integrationsMock = [() => { }];
 

src/utils/settingsValidation/__tests__/settings.mocks.ts

@@ -78,7 +78,8 @@ export const fullSettings: ISettings = {
       validFilters: [],
       queryString: null,
       groupedFilters: { byName: [], byPrefix: [] }
-    }
+    },
+    singleSync: false
   },
   version: 'jest',
   runtime: {

src/utils/settingsValidation/index.ts

@@ -83,7 +83,8 @@ export const base = {
     splitFilters: undefined,
     // impressions collection mode
     impressionsMode: OPTIMIZED,
-    localhostMode: undefined
+    localhostMode: undefined,
+    singleSync: false
   },
 
   // Logger
@@ -191,6 +192,11 @@ export function settingsValidation(config: unknown, validationParams: ISettingsV
     scheduler.pushRetryBackoffBase = fromSecondsToMillis(scheduler.pushRetryBackoffBase);
   }
 
+  // validate singleSync
+  if (withDefaults.sync.singleSync !== true) { // @ts-ignore, modify readonly prop
+    withDefaults.sync.singleSync = false;
+  }
+
   // validate the `splitFilters` settings and parse splits query
   const splitFiltersValidation = validateSplitFilters(log, withDefaults.sync.splitFilters, withDefaults.mode);
   withDefaults.sync.splitFilters = splitFiltersValidation.validFilters;