Lit UI Router

ui-router-server / prerender / prerender

Function: prerender() ​

ts
function prerender(options): Promise<PrerenderResult>;

Defined in: prerender.ts:468

Emits a static site from a mount table's verdicts: a shell verdict becomes <subpath>/index.html holding whatever render returns, or a rules line when render answers a RenderedRedirect, a response state becomes the body or rules line its respond answer carries, a redirect becomes a rules line and no page, a delegating state is listed in delegated and skipped, and the otherwise projection becomes the 404 document. A verdict kind this package doesn't know throws rather than being counted.

Rules lines follow each mount's config.trailingSlash policy. Where it spells a page or a response state 'always' or 'never', the output lands at the path listed and the other spelling gets the 308 line onto it that the server answers; list each path in its canonical spelling, as href() formats it under `applyUrlConfig`. Under 'as-requested' neither spelling gets a line. A redirect's line is written for both spellings of its path, since a static host may append the slash. Under a base, every generated line carries it.

It knows no renderer: render turns each shell verdict into the file's text, so any template engine, or a settle and a string, can fill it. lit-ui-router-ssr's prerender wraps this loop with a lit render.

Parameters ​

ParameterTypeDescription
optionsPrerenderOptionsthe mount table, the paths, the render, and the hooks

Returns ​

Promise<PrerenderResult>

what was emitted, planned or written

Throws ​

an Error when neither mounts nor resolver is supplied

Throws ​

an Error when base is relative or a full URL, or differs from the resolver's

Throws ​

an Error when a mount of a resolver that declares no base already carries base

Throws ​

an Error when the 404 document needs a default probe and only a resolver is supplied

Throws ​

an Error when a path resolves to a verdict kind this package doesn't know

Throws ​

an Error when the 404 document's render answers a redirect

Throws ​

an Error when a path matches a response state and no respond is supplied, or its answer is neither a 2xx nor a 3xx with a Location

Example ​

ts
import type { UIRouter } from '@uirouter/core';
import { mkdir, writeFile } from 'node:fs/promises';
import { dirname } from 'node:path';
import { prerender, type PrerenderOptions } from 'ui-router-server/prerender';
import { settle } from 'ui-router-server/ssr';

declare const mounts: PrerenderOptions['mounts'];
declare const router: UIRouter;
declare function page(router: UIRouter): string;

const result = await prerender({
  mounts,
  outDir: 'dist',
  write: async (file, body) => {
    await mkdir(dirname(file), { recursive: true });
    await writeFile(file, body);
  },
  paths: ['/', '/sheet/7B', '/legacy'],
  render: async (verdict, { path }) => {
    await settle(router, path);
    return page(router);
  },
});