[vercel/flags-core] allow json flags

.changeset/bright-jars-flow.md

@@ -0,0 +1,5 @@
+---
+"@vercel/flags-core": minor
+---
+
+Support object/JSON flag values in addition to boolean, string, and number

packages/vercel-flags-core/src/black-box.test.ts

@@ -2879,6 +2879,10 @@ describe('Controller (black-box)', () => {
             environments: { production: 0 },
             variants: [42],
           },
+          jsonFlag: {
+            environments: { production: 0 },
+            variants: [{ color: 'red', size: 12 }],
+          },
         },
       });
 
@@ -2893,6 +2897,10 @@ describe('Controller (black-box)', () => {
       expect((await client.evaluate('boolFlag')).value).toBe(true);
       expect((await client.evaluate('stringFlag')).value).toBe('hello');
       expect((await client.evaluate('numberFlag')).value).toBe(42);
+      expect((await client.evaluate('jsonFlag')).value).toEqual({
+        color: 'red',
+        size: 12,
+      });
     });
 
     it('should call internalReportValue when projectId exists', async () => {

packages/vercel-flags-core/src/index.common.ts

@@ -19,8 +19,12 @@ export {
   type EvaluationParams,
   type EvaluationResult,
   type FlagsClient,
+  type JsonArray,
+  type JsonObject,
+  type JsonValue,
   type Packed,
   type PollingOptions,
   ResolutionReason as Reason,
   type StreamOptions,
+  type Value,
 } from './types';

packages/vercel-flags-core/src/types.ts

@@ -1,5 +1,3 @@
-import type { ControllerInstance } from './controller-fns';
-
 /**
  * Options for stream connection behavior
  */
@@ -249,7 +247,17 @@ export type FlagKey = string;
 export type VariantId = string;
 export type EnvironmentKey = string;
 export type SegmentId = string;
-export type Value = string | number | boolean;
+export type JsonObject = { [key: string]: JsonValue };
+export type JsonArray = JsonValue[];
+export type JsonValue =
+  | string
+  | number
+  | boolean
+  | null
+  | JsonObject
+  | JsonArray;
+
+export type Value = string | number | boolean | JsonObject | JsonArray;
 
 export enum ResolutionReason {
   PAUSED = 'paused',