reverse proxy info

static/js/api.js

@@ -1,6 +1,26 @@
 import { logDebug, logError, logWarn } from "./logger.js";
 
+function formatBytes(bytes) {
+  if (bytes >= 1024 * 1024) return `${(bytes / (1024 * 1024)).toFixed(bytes % (1024 * 1024) ? 1 : 0)} MB`;
+  if (bytes >= 1024) return `${Math.ceil(bytes / 1024)} KB`;
+  return `${bytes} B`;
+}
+
+function validateUploadSize(body) {
+  if (!(body instanceof FormData)) return;
+  const maxBytes = Number(window.__RUSTPAD_CONFIG__?.uploadMaxSizeBytes || 0);
+  if (!Number.isFinite(maxBytes) || maxBytes <= 0) return;
+  for (const value of body.values()) {
+    if (value instanceof File && value.size > maxBytes) {
+      const error = new Error(`The selected file is ${formatBytes(value.size)}. The upload limit is ${formatBytes(maxBytes)}.`);
+      error.status = 413;
+      throw error;
+    }
+  }
+}
+
 export async function api(path, options = {}) {
+  validateUploadSize(options.body);
   const controller = new AbortController();
   const timeout = setTimeout(() => controller.abort(), 12000);
   try {
@@ -24,6 +44,9 @@ export async function api(path, options = {}) {
   } catch (error) {
     if (error.name === "AbortError") { logWarn("api.timeout", { method: options.method || "GET", path }); throw new Error("Timed out"); }
     logError("api.network_error", error, { method: options.method || "GET", path });
+    if (options.body instanceof FormData && error instanceof TypeError) {
+      throw new Error("Upload failed before the server returned a response. The file may exceed the server or proxy upload limit.");
+    }
     throw error;
   } finally { clearTimeout(timeout); }
 }