Add validation to check if backendId exists when --only flag is used (#10170)

aalej · joehan · web-flow · commit 0e1c2595d41c · 2026-03-31T18:38:12.000Z
* add validation to check if backendId exists when --only flag is used

* add changelog entry

* add tests

* typo

---------

Co-authored-by: Joe Hanley &lt;joehanley@google.com&gt;
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -0,0 +1 @@
+- Add validation to check if backendId exists in `firebase.json` when `--only` flag is used. (#10161)
diff --git a/src/deploy/apphosting/prepare.spec.ts b/src/deploy/apphosting/prepare.spec.ts
@@ -479,6 +479,18 @@ describe("apphosting", () => {
         },
       ]);
     });
+
+    it("throws error when no backend ID in firebase.json matches the one provided in --only flag", () => {
+      expect(() =>
+        getBackendConfigs({
+          ...BASE_OPTS,
+          only: "apphosting:baz",
+          config: new Config({
+            apphosting: apphostingConfig,
+          }),
+        }),
+      ).to.throw("App Hosting backend IDs baz not detected in firebase.json");
+    });
   });
 
   describe("injectEnvVarsFromApphostingConfig", () => {
diff --git a/src/deploy/apphosting/prepare.ts b/src/deploy/apphosting/prepare.ts
@@ -309,7 +309,17 @@ export function getBackendConfigs(options: Options): AppHostingMultiple {
   if (backendIds.length === 0) {
     return [];
   }
-  return backendConfigs.filter((cfg) => backendIds.includes(cfg.backendId));
+
+  const filteredConfigs = backendConfigs.filter((cfg) => backendIds.includes(cfg.backendId));
+  const foundIds = filteredConfigs.map((cfg) => cfg.backendId);
+  const missingIds = backendIds.filter((id) => !foundIds.includes(id));
+  if (missingIds.length > 0) {
+    throw new FirebaseError(
+      `App Hosting backend IDs ${missingIds.join(",")} not detected in firebase.json`,
+    );
+  }
+
+  return filteredConfigs;
 }
 
 /**

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1 @@`
	`1`	+- Add validation to check if backendId exists in `firebase.json` when `--only` flag is used. (#10161)