fix: remove hardcoded horizon URL and dynamic URL generation (#21)

* refactor: remove hardcoded horizon URL and implement dynamic URL generation

* fix: validate organization ID format in public key extraction

* refactor: rename horizonServerUrls to horizonUrls

Author: chrisllontop

src/config.ts

@@ -1,7 +1,3 @@
-export const horizon = {
-  url: `https://horizon.hyphen.ai`,
-};
-
 export const cache = {
   ttlSeconds: process.env.CACHE_TTL_SECONDS ? parseInt(process.env.CACHE_TTL_SECONDS) : 30,
 };

src/hyphenClient.ts

@@ -1,23 +1,25 @@
 import type { EvaluationResponse, HyphenEvaluationContext, HyphenProviderOptions, TelemetryPayload } from './types';
-import { horizon } from './config';
 import type { Logger } from '@openfeature/server-sdk';
 import { CacheClient } from './cacheClient';
+import { buildDefaultHorizonUrl } from './utils';
 
 export class HyphenClient {
   private readonly publicKey: string;
-  private readonly horizonServerUrls: string[];
+  private readonly horizonUrls: string[];
+  private readonly defaultHorizonUrl: string;
   private cache: CacheClient;
 
   constructor(publicKey: string, options: HyphenProviderOptions) {
     this.publicKey = publicKey;
-    this.horizonServerUrls = [...(options.horizonServerUrls || []), horizon.url];
+    this.defaultHorizonUrl = buildDefaultHorizonUrl(publicKey);
+    this.horizonUrls = [...(options.horizonServerUrls || []), this.defaultHorizonUrl];
     this.cache = new CacheClient(options.cache);
   }
 
   private async tryUrls(urlPath: string, payload: unknown, logger?: Logger): Promise<Response> {
     let lastError: unknown;
 
-    for (let url of this.horizonServerUrls) {
+    for (let url of this.horizonUrls) {
       try {
         const baseUrl = new URL(url);
         const basePath = baseUrl.pathname.replace(/\/$/, '');

src/utils.ts

@@ -0,0 +1,16 @@
+export function getOrgIdFromPublicKey(publicKey: string) {
+  try {
+    const keyWithoutPrefix = publicKey.replace(/^public_/, '');
+    const decoded = Buffer.from(keyWithoutPrefix, 'base64').toString();
+    const [orgId] = decoded.split(':');
+    const isValidOrgId = /^[a-zA-Z0-9_-]+$/.test(orgId);
+    return isValidOrgId ? orgId : undefined;
+  } catch {
+    return undefined;
+  }
+}
+
+export function buildDefaultHorizonUrl(publicKey: string): string {
+  const orgId = getOrgIdFromPublicKey(publicKey);
+  return orgId ? `https://${orgId}.toggle.hyphen.cloud` : 'https://toggle.hyphen.cloud';
+}

tests/config.test.ts

@@ -12,14 +12,6 @@ describe('Config', () => {
     process.env = originalEnv;
   });
 
-  describe('horizon', () => {
-    it('should use production URL when NODE_ENV is production', async () => {
-      process.env.NODE_ENV = 'production';
-      const { horizon } = await import('../src/config');
-      expect(horizon.url).toBe('https://horizon.hyphen.ai');
-    });
-  });
-
   describe('cache', () => {
     it('should use default TTL when CACHE_TTL_SECONDS is not set', async () => {
       delete process.env.CACHE_TTL_SECONDS;

tests/hyphenClient.test.ts

@@ -16,8 +16,9 @@ vi.mock('../src/config', () => {
 vi.stubGlobal('fetch', vi.fn());
 
 describe('HyphenClient', () => {
-  const publicKey = 'test-public-key';
-  const mockUrl = 'https://mock-horizon-url.com';
+  const publicKey = 'public_b3JnLTEyMzpwcm9qZWN0OnJhbmRvbTEyMw==';
+  const organizationId = 'org-123';
+  const mockUrl = `https://${organizationId}.toggle.hyphen.cloud`;
   const mockEvaluateUrl = `${mockUrl}/toggle/evaluate`;
   const mockTelemetryUrl = `${mockUrl}/toggle/telemetry`;
   const mockContext: HyphenEvaluationContext = {
@@ -180,7 +181,7 @@ describe('HyphenClient', () => {
 
   it('should add horizon URL if not present in the server URLs', () => {
     const client = new HyphenClient(publicKey, options);
-    expect(client['horizonServerUrls']).toEqual([mockUrl]);
+    expect(client['horizonUrls']).toEqual([mockUrl]);
   });
 
   it('should handle non-successful responses and set the lastError', async () => {