fix: avoid chrome process hanging while prerendering

Author: harlan-zw

Diff for: src/runtime/core/cache/prerender.ts

@@ -1,12 +1,9 @@
 import { createStorage } from 'unstorage'
 import lruCacheDriver from 'unstorage/drivers/lru-cache'
-import type { Browser } from 'playwright-core'
 import type { OgImageOptions } from '../../types'
 
 export const prerenderOptionsCache = import.meta.prerender
   ? createStorage<OgImageOptions>({
     driver: lruCacheDriver({ max: 1000 }),
   })
   : undefined
-
-export const prerenderChromiumContext: { browser?: Browser } = { browser: undefined }

Diff for: src/runtime/core/renderers/chromium/index.ts

@@ -1,6 +1,5 @@
 import type { Browser } from 'playwright-core'
 import type { Renderer } from '../../../types'
-import { prerenderChromiumContext } from '../../cache/prerender'
 import { createScreenshot } from './screenshot'
 import { createBrowser } from '#nuxt-og-image/bindings/chromium'
 
@@ -11,16 +10,8 @@ const ChromiumRenderer: Renderer = {
     return {} // TODO
   },
   async createImage(ctx) {
-    let browser: Browser = (import.meta.prerender ? prerenderChromiumContext.browser : null) || await createBrowser()
+    const browser: Browser = await createBrowser()
     // check if browser is open
-    // lets us re-use the browser
-    if (import.meta.prerender) {
-      prerenderChromiumContext.browser = browser
-      // if not, open it
-      if (!browser.isConnected())
-        browser = await createBrowser()
-    }
-
     if (!browser.isConnected()) {
       return createError({
         statusCode: 400,
@@ -29,9 +20,8 @@ const ChromiumRenderer: Renderer = {
     }
 
     // @todo return placeholder image on failure
-    return createScreenshot(ctx, browser!).finally(async () => {
-      if (!import.meta.prerender) // closed by
-        await browser!.close()
+    return await createScreenshot(ctx, browser!).finally(async () => {
+      await browser!.close()
     })
   },
 }

Diff for: src/runtime/nitro/plugins/prerender.ts

@@ -4,7 +4,7 @@ import { createRouter as createRadixRouter, toRouteMatcher } from 'radix3'
 import { defu } from 'defu'
 import type { NitroRouteRules } from 'nitropack'
 import { extractAndNormaliseOgImageOptions } from '../../core/options/extract'
-import { prerenderChromiumContext, prerenderOptionsCache } from '../../core/cache/prerender'
+import { prerenderOptionsCache } from '../../core/cache/prerender'
 import { isInternalRoute } from '../../utils.pure'
 import { resolvePathCacheKey } from '../utils'
 import { useRuntimeConfig } from '#imports'
@@ -38,11 +38,4 @@ export default defineNitroPlugin(async (nitro) => {
     const key = resolvePathCacheKey(ctx.event)
     await prerenderOptionsCache!.setItem(key, options)
   })
-  nitro.hooks.hook('close', async () => {
-    // clean up the browser
-    if (prerenderChromiumContext.browser) {
-      await prerenderChromiumContext.browser.close()
-      prerenderChromiumContext.browser = undefined
-    }
-  })
 })