fix(dev): serve an unpublished app through its preview URL with --remote

CHANGELOG.md

@@ -18,7 +18,7 @@
 - App visibility: `base44 visibility <public|private|workspace>` sets it on the server directly (accepts `--app-id` to target any app). Also configurable via `"visibility"` in `config.jsonc`, which `base44 deploy` applies. New projects scaffold `"visibility": "public"`.
 - `base44 build` runs the site's `buildCommand` with `VITE_BASE44_APP_ID` injected, so built bundles always carry the linked app's id.
 - `base44 deploy` (and `base44 site deploy`) can now build first: interactive runs ask, and `--build` / `--no-build` pre-answer the prompt.
-- `base44 dev --remote` serves the frontend against the production backend: it runs `site.serveCommand` with `VITE_BASE44_APP_ID` and `VITE_BASE44_APP_BASE_URL` pointing at the app's own published URL, without starting the local backend. Fails if the app has no published URL.
+- `base44 dev --remote` serves the frontend against the production backend: it runs `site.serveCommand` with `VITE_BASE44_APP_ID` and `VITE_BASE44_APP_BASE_URL` pointing at the app's own published URL, without starting the local backend. An app that was never published is served through its preview URL (`https://preview--<appId>.base44.app`), as `base44 exec` does.
 
 ### Changed
 

packages/cli/src/cli/commands/dev.ts

@@ -13,6 +13,7 @@ import { getDenoWrapperPath } from "@/core/assets.js";
 import { BASE44_APP_ID_ENV_VAR } from "@/core/consts.js";
 import { ConfigInvalidError } from "@/core/errors.js";
 import { getSiteUrl } from "@/core/project/api.js";
+import { resolveAppBaseUrl } from "@/core/project/app-base-url.js";
 import { readProjectConfig } from "@/core/project/config.js";
 
 interface DevOptions {
@@ -91,7 +92,7 @@ async function remoteDevAction(app: LinkedApp): Promise<RunCommandResult> {
     );
   }
 
-  const appBaseUrl = await getSiteUrl();
+  const appBaseUrl = await resolveAppBaseUrl(app.id);
   const runner = createServeCommandRunner({
     ...site,
     appId: app.id,

packages/cli/src/core/exec/run-script.ts

@@ -3,13 +3,13 @@ import { readFileSync, writeFileSync } from "node:fs";
 import { join } from "node:path";
 import { dir, file } from "tmp-promise";
 import { getExecWrapperPath } from "@/core/assets.js";
-import { ApiError } from "@/core/errors.js";
 import {
   DATA_ENV_ENV_VAR,
   EXEC_ENV_VARS,
   PRIVILEGED_ENV_VAR,
 } from "@/core/exec/env-target.js";
-import { getAppUserToken, getSiteUrl } from "@/core/project/api.js";
+import { getAppUserToken } from "@/core/project/api.js";
+import { resolveAppBaseUrl } from "@/core/project/app-base-url.js";
 import { verifyDenoInstalled } from "@/core/utils/index.js";
 
 interface RunScriptOptions {
@@ -58,19 +58,6 @@ function inheritedEnv(): NodeJS.ProcessEnv {
   return env;
 }
 
-const appPreviewUrl = (appId: string) => `https://preview--${appId}.base44.app`;
-
-async function resolveAppBaseUrl(appId: string) {
-  try {
-    return await getSiteUrl();
-  } catch (error) {
-    if (error instanceof ApiError && error.statusCode === 404) {
-      return appPreviewUrl(appId);
-    }
-    throw error;
-  }
-}
-
 interface RunScriptResult {
   exitCode: number;
 }

packages/cli/src/core/project/app-base-url.ts

@@ -0,0 +1,16 @@
+import { ApiError } from "@/core/errors.js";
+import { getSiteUrl } from "@/core/project/api.js";
+
+const appPreviewUrl = (appId: string) => `https://preview--${appId}.base44.app`;
+
+const isAppNotPublished = (error: unknown) =>
+  error instanceof ApiError && error.statusCode === 404;
+
+export async function resolveAppBaseUrl(appId: string) {
+  try {
+    return await getSiteUrl();
+  } catch (error) {
+    if (isAppNotPublished(error)) return appPreviewUrl(appId);
+    throw error;
+  }
+}

packages/cli/tests/cli/dev.spec.ts

@@ -116,10 +116,22 @@ describe("dev command", () => {
     expect(output).not.toContain("Backend running on");
   });
 
-  it("--remote fails when the app has no published URL", async () => {
+  it("--remote serves an unpublished app through its preview URL", async () => {
     await t.givenLoggedInWithProject(fixture("with-serve-command"));
     t.api.mockSiteUrlError({ status: 404, body: { detail: "App not found" } });
 
+    const handle = await t.runLive("dev", "--remote");
+    await handle.waitForOutput(/SERVE_APP=/);
+    await handle.stop();
+
+    const output = handle.stdout.join("");
+    expect(output).toContain(`URL=https://preview--${t.api.appId}.base44.app`);
+  });
+
+  it("--remote fails when the site URL lookup fails for another reason", async () => {
+    await t.givenLoggedInWithProject(fixture("with-serve-command"));
+    t.api.mockSiteUrlError({ status: 500, body: { detail: "Server error" } });
+
     const result = await t.run("dev", "--remote");
 
     t.expectResult(result).toFail();