headscale: read the invite list out of whatever envelope the companion sends

src/servers/sidecar/headscale/invites.ts

@@ -104,10 +104,27 @@ async function create(creds: HeadscaleServerCredentials, ctx: OfficerContext): P
   return relay(res, (body) => ({ available: true, invite: body.invite ?? body }));
 }
 
+/**
+ * Pull the invite array out of whatever envelope the companion used.
+ *
+ * §4.3 specifies the fields but not the wrapper, and the create response came back flat (no `invite` key),
+ * so the list may equally be a bare array or sit under `invites`/`items`/`data`. Taking the first
+ * array-valued property is shape-agnostic without being credulous: the body has exactly one array in it.
+ */
+function pickInvites(body: Record<string, unknown>): unknown[] {
+  if (Array.isArray(body)) return body;
+  for (const key of ['invites', 'items', 'data', 'results']) {
+    const value = body[key];
+    if (Array.isArray(value)) return value;
+  }
+  const found = Object.values(body).find(Array.isArray);
+  return Array.isArray(found) ? found : [];
+}
+
 /** `GET /_officer/enroll/invites` — the admin's audit list. Never carries a token or a key. */
 async function list(creds: HeadscaleServerCredentials): Promise<Response> {
   const res = await callCompanion(creds, { path: INVITES_PATH });
-  return relay(res, (body) => ({ available: true, invites: Array.isArray(body.invites) ? body.invites : [] }));
+  return relay(res, (body) => ({ available: true, invites: pickInvites(body) }));
 }
 
 /** `DELETE /_officer/enroll/invites/:id` — revoke an unclaimed invite. A no-op on a claimed one. */