feat: import public non-asset URL

packages/vite/src/node/plugins/asset.ts

@@ -28,7 +28,7 @@ import { FS_PREFIX } from '../constants'
 export const assetUrlRE = /__VITE_ASSET__([a-z\d]+)__(?:\$_(.*?)__)?/g
 
 const rawRE = /(?:\?|&)raw(?:&|$)/
-const urlRE = /(\?|&)url(?:&|$)/
+export const urlRE = /(\?|&)url(?:&|$)/
 const jsSourceMapRE = /\.[cm]?js\.map$/
 const unnededFinalQueryCharRE = /[?&]$/
 
@@ -146,7 +146,7 @@ export function assetPlugin(config: ResolvedConfig): Plugin {
  },
 
  resolveId(id) {
- if (!config.assetsInclude(cleanUrl(id))) {
+ if (!config.assetsInclude(cleanUrl(id)) && !urlRE.test(id)) {
  return
  }
  // imports to absolute urls pointing to files in /public

packages/vite/src/node/plugins/importAnalysis.ts

@@ -54,7 +54,7 @@ import {
  shouldExternalizeForSSR,
 } from '../ssr/ssrExternal'
 import { getDepsOptimizer, optimizedDepNeedsInterop } from '../optimizer'
-import { checkPublicFile } from './asset'
+import { checkPublicFile, urlRE } from './asset'
 import {
  ERR_OUTDATED_OPTIMIZED_DEP,
  throwOutdatedRequest,
@@ -506,14 +506,20 @@ export function importAnalysisPlugin(config: ResolvedConfig): Plugin {
  // warn imports to non-asset /public files
  if (
  specifier[0] === '/' &&
- !config.assetsInclude(cleanUrl(specifier)) &&
- !specifier.endsWith('.json') &&
+ !(
+ config.assetsInclude(cleanUrl(specifier)) ||
+ urlRE.test(specifier)
+ ) &&
  checkPublicFile(specifier, config)
  ) {
  throw new Error(
- `Cannot import non-asset file ${specifier} which is inside /public.` +
+ `Cannot import non-asset file ${specifier} which is inside /public. ` +
  `JS/CSS files inside /public are copied as-is on build and ` +
- `can only be referenced via <script src> or <link href> in html.`,
+ `can only be referenced via <script src> or <link href> in html. ` +
+ `If you want to get the URL of that file, use ${injectQuery(
+ specifier,
+ 'url',
+ )} instead.`,
  )
  }
 

packages/vite/src/node/server/middlewares/transform.ts

@@ -36,6 +36,7 @@ import {
  ERR_OUTDATED_OPTIMIZED_DEP,
 } from '../../plugins/optimizedDeps'
 import { getDepsOptimizer } from '../../optimizer'
+import { urlRE } from '../../plugins/asset'
 
 const debugCache = createDebugger('vite:cache')
 
@@ -135,14 +136,22 @@ export function transformMiddleware(
 
  if (isImportRequest(url)) {
  const rawUrl = removeImportQuery(url)
-
- warning =
- 'Assets in public cannot be imported from JavaScript.\n' +
- `Instead of ${colors.cyan(
- rawUrl,
- )}, put the file in the src directory, and use ${colors.cyan(
- rawUrl.replace(publicPath, '/src/'),
- )} instead.`
+ if (urlRE.test(url)) {
+ warning =
+ `Assets in the public directory are served at the root path.\n` +
+ `Instead of ${colors.cyan(rawUrl)}, use ${colors.cyan(
+ rawUrl.replace(publicPath, '/'),
+ )}.`
+ } else {
+ warning =
+ 'Assets in public directory cannot be imported from JavaScript.\n' +
+ `If you intend to import that asset, put the file in the src directory, and use ${colors.cyan(
+ rawUrl.replace(publicPath, '/src/'),
+ )} instead of ${colors.cyan(rawUrl)}.\n` +
+ `If you intend to use the URL of that asset, use ${colors.cyan(
+ injectQuery(rawUrl.replace(publicPath, '/'), 'url'),
+ )}.`
+ }
  } else {
  warning =
  `files in the public directory are served at the root path.\n` +

playground/assets/__tests__/assets.spec.ts

@@ -100,6 +100,19 @@ describe('asset imports from js', () => {
  test('from /public', async () => {
  expect(await page.textContent('.public-import')).toMatch(iconMatch)
  })
+
+ test('from /public (json)', async () => {
+ expect(await page.textContent('.public-json-import')).toMatch(
+ '/foo/foo.json',
+ )
+ expect(await page.textContent('.public-json-import-content'))
+ .toMatchInlineSnapshot(`
+ "{
+ \\"foo\\": \\"bar\\"
+ }
+ "
+ `)
+ })
 })
 
 describe('css url() references', () => {

playground/assets/index.html

@@ -26,6 +26,10 @@ <h2>Asset Imports from JS</h2>
  <li>Relative: <code class="asset-import-relative"></code></li>
  <li>Absolute: <code class="asset-import-absolute"></code></li>
  <li>From publicDir: <code class="public-import"></code></li>
+ <li>
+ From publicDir (json): <code class="public-json-import"></code> Content:
+ <code class="public-json-import-content"></code>
+ </li>
 </ul>
 
 <h2>CSS url references</h2>
@@ -377,6 +381,13 @@ <h3>assets in noscript</h3>
  import publicUrl from '/icon.png'
  text('.public-import', publicUrl)
 
+ import publicJsonUrl from '/foo.json?url'
+ text('.public-json-import', publicJsonUrl)
+ ;(async () => {
+ const res = await fetch(publicJsonUrl)
+ text('.public-json-import-content', await res.text())
+ })()
+
  import svgFrag from './nested/fragment.svg'
  text('.svg-frag-import-path', svgFrag)
  document.querySelector('.svg-frag-import').src = svgFrag + '#icon-heart-view'

playground/assets/static/foo.json

@@ -0,0 +1,3 @@
+{
+ "foo": "bar"
+}