Server Errors

async_local_storage_unavailable

The node API `AsyncLocalStorage` is not available, but is required to use async server rendering.

Some platforms require configuration flags to enable this API. Consult your platform's documentation.

await_invalid

Encountered asynchronous work while rendering synchronously.

You (or the framework you're using) called render(...) with a component containing an await expression. Either await the result of render or wrap the await (or the component containing it) in a <svelte:boundary> with a pending snippet.

dynamic_element_invalid_tag

`<svelte:element this="%tag%">` is not a valid element name — the element will not be rendered

The value passed to the this prop of <svelte:element> must be a valid HTML element, SVG element, MathML element, or custom element name. A value containing invalid characters (such as whitespace or special characters) was provided, which could be a security risk. Ensure only valid tag names are passed.

html_deprecated

The `html` property of server render results has been deprecated. Use `body` instead.

hydratable_clobbering

Attempted to set `hydratable` with key `%key%` twice with different values.

%stack%

This error occurs when using hydratable multiple times with the same key. To avoid this, you can:

• Ensure all invocations with the same key result in the same value
• Update the keys to make both instances unique

<script>
  import { hydratable } from 'svelte';

  // which one should "win" and be serialized in the rendered response?
  const one = hydratable('not-unique', () => 1);
  const two = hydratable('not-unique', () => 2);
</script>

hydratable_serialization_failed

Failed to serialize `hydratable` data for key `%key%`.

`hydratable` can serialize anything [`uneval` from `devalue`](https://npmjs.com/package/uneval) can, plus Promises.

Cause:
%stack%

invalid_csp

`csp.nonce` was set while `csp.hash` was `true`. These options cannot be used simultaneously.

lifecycle_function_unavailable

`%name%(...)` is not available on the server

Certain methods such as mount cannot be invoked while running in a server context. Avoid calling them eagerly, i.e. not during render.

server_context_required

Could not resolve `render` context.

Certain functions such as hydratable cannot be invoked outside of a render(...) call, such as at the top level of a module.