feat(frontend): Implement runtime API URL configuration and entrypoint script

- Add docker-entrypoint.sh to dynamically set API URL at runtime
- Update API URL retrieval logic in client.ts and voice.ts to prioritize runtime configuration
- Modify Dockerfile.prod to include entrypoint script and ensure executable permissions
- Enhance flexibility for API URL configuration in production environments

Author: chandra447

frontend/Dockerfile.prod

@@ -35,6 +35,11 @@ COPY --from=builder /app/public ./public
 COPY --from=builder /app/next.config.ts ./next.config.ts
 COPY --from=builder /app/node_modules ./node_modules
 
+# Copy entrypoint script for runtime configuration
+COPY docker-entrypoint.sh /docker-entrypoint.sh
+RUN chmod +x /docker-entrypoint.sh
+
 EXPOSE 3000
+ENTRYPOINT ["/docker-entrypoint.sh"]
 CMD ["npm", "run", "start"]
 

frontend/lib/api/client.ts

@@ -7,7 +7,15 @@ import { getAccessToken, isTokenExpired, getRefreshToken, storeTokens, clearToke
 import { refreshToken as refreshTokenApi } from './auth';
 
 const getApiBaseUrl = () => {
-  // Use environment variable (baked in at build time) or fallback to localhost for dev
+  // Check for runtime config first (injected by docker-entrypoint.sh in production)
+  if (typeof window !== 'undefined' && (window as any).NEXT_PUBLIC_API_URL) {
+    const runtimeUrl = (window as any).NEXT_PUBLIC_API_URL;
+    // Don't use placeholder value
+    if (runtimeUrl !== '__PLACEHOLDER__') {
+      return runtimeUrl;
+    }
+  }
+  // Fallback to build-time environment variable or localhost for dev
   return process.env.NEXT_PUBLIC_API_URL || 'http://localhost:8000';
 };
 

frontend/lib/api/voice.ts

@@ -4,8 +4,19 @@
 
 import { getAccessToken } from '../auth/token-storage';
 
-// Use environment variable (baked in at build time) or fallback to localhost for dev
-const API_BASE_URL = process.env.NEXT_PUBLIC_API_URL || 'http://localhost:8000';
+// Get API base URL from runtime config or build-time env var
+const getApiBaseUrl = () => {
+  // Check for runtime config first (injected by docker-entrypoint.sh in production)
+  if (typeof window !== 'undefined' && (window as any).NEXT_PUBLIC_API_URL) {
+    const runtimeUrl = (window as any).NEXT_PUBLIC_API_URL;
+    // Don't use placeholder value
+    if (runtimeUrl !== '__PLACEHOLDER__') {
+      return runtimeUrl;
+    }
+  }
+  // Fallback to build-time environment variable or localhost for dev
+  return process.env.NEXT_PUBLIC_API_URL || 'http://localhost:8000';
+};
 
 export interface VoiceTranscript {
   role: 'user' | 'assistant';
@@ -41,10 +52,11 @@ export function connectVoiceAgent(
   testMode: boolean = false
 ): WebSocket {
   const accessToken = getAccessToken();
+  const apiBaseUrl = getApiBaseUrl();
 
   // WebSocket URL (ws:// for http, wss:// for https)
-  const wsProtocol = API_BASE_URL.startsWith('https') ? 'wss' : 'ws';
-  const wsBaseUrl = API_BASE_URL.replace(/^https?:\/\//, '');
+  const wsProtocol = apiBaseUrl.startsWith('https') ? 'wss' : 'ws';
+  const wsBaseUrl = apiBaseUrl.replace(/^https?:\/\//, '');
 
   // Build URL with test mode or API key
   let url = `${wsProtocol}://${wsBaseUrl}/api/v1/voice/${agentId}/${actorId}/${sessionId}`;