Implement dev mode header for API requests

src/client.ts

@@ -66,8 +66,14 @@ export function createClient(config: CreateClientConfig): Base44Client {
     options,
     functionsVersion,
     headers: optionalHeaders,
+    useStagingDb: configUseStagingDb,
   } = config;
 
+  // Config takes precedence, fallback to URL query param in browser
+  const urlHasStagingDb = typeof window !== "undefined"
+    && new URLSearchParams(window.location.search).get("use_staging_db") === "true";
+  const useStagingDb = configUseStagingDb ?? urlHasStagingDb;
+
   const socketConfig: RoomsSocketConfig = {
     serverUrl,
     mountPath: "/ws-user-apps/socket.io/",
@@ -90,6 +96,7 @@ export function createClient(config: CreateClientConfig): Base44Client {
   const headers = {
     ...optionalHeaders,
     "X-App-Id": String(appId),
+    "Base44-Use-Staging-DB": String(useStagingDb),
   };
 
   const functionHeaders = functionsVersion
@@ -346,6 +353,7 @@ export function createClientFromRequest(request: Request): Base44Client {
   const appId = request.headers.get("Base44-App-Id");
   const serverUrlHeader = request.headers.get("Base44-Api-Url");
   const functionsVersion = request.headers.get("Base44-Functions-Version");
+  const useStagingDb = request.headers.get("Base44-Use-Staging-DB") === "true";
   const stateHeader = request.headers.get("Base44-State");
 
   if (!appId) {
@@ -396,6 +404,7 @@ export function createClientFromRequest(request: Request): Base44Client {
     token: userToken,
     serviceToken: serviceRoleToken,
     functionsVersion: functionsVersion ?? undefined,
+    useStagingDb: useStagingDb ?? undefined,
     headers: additionalHeaders,
   });
 }

src/client.types.ts

@@ -62,6 +62,11 @@ export interface CreateClientConfig {
    * @internal
    */
   headers?: Record<string, string>;
+  /**
+   * Whether to use the staging database. Defaults to false.
+   * When true, API requests will use the staging database instead of production.
+   */
+  useStagingDb?: boolean;
   /**
    * Additional client options.
    */

tests/unit/client.test.js

@@ -254,7 +254,46 @@ describe('createClientFromRequest', () => {
     };
 
     const client = createClientFromRequest(mockRequest);
-
+
+    expect(client).toBeDefined();
+    const config = client.getConfig();
+    expect(config.appId).toBe('test-app-id');
+  });
+
+  test('should propagate Base44-Use-Staging-DB header when present', () => {
+    const mockRequest = {
+      headers: {
+        get: (name) => {
+          const headers = {
+            'Base44-App-Id': 'test-app-id',
+            'Base44-Use-Staging-DB': 'true'
+          };
+          return headers[name] || null;
+        }
+      }
+    };
+
+    const client = createClientFromRequest(mockRequest);
+
+    expect(client).toBeDefined();
+    const config = client.getConfig();
+    expect(config.appId).toBe('test-app-id');
+  });
+
+  test('should work without Base44-Use-Staging-DB header', () => {
+    const mockRequest = {
+      headers: {
+        get: (name) => {
+          const headers = {
+            'Base44-App-Id': 'test-app-id'
+          };
+          return headers[name] || null;
+        }
+      }
+    };
+
+    const client = createClientFromRequest(mockRequest);
+
     expect(client).toBeDefined();
     const config = client.getConfig();
     expect(config.appId).toBe('test-app-id');