feat: use edge function layer for ipx (#1880)

Co-authored-by: Nick Taylor <nick@iamdeveloper.com>

Author: ascorbic

packages/runtime/src/helpers/edge.ts

@@ -65,6 +65,7 @@ export interface FunctionManifest {
         cache?: 'manual'
       }
   >
+  layers?: Array<{ name: `https://${string}/mod.ts`; flag: string }>
   import_map?: string
 }
 
@@ -345,6 +346,7 @@ export const writeEdgeFunctions = async ({
 }) => {
   const manifest: FunctionManifest = {
     functions: [],
+    layers: [],
     version: 1,
   }
 
@@ -473,7 +475,12 @@ export const writeEdgeFunctions = async ({
     manifest.functions.push({
       function: 'ipx',
       name: 'next/image handler',
-      path: '/_next/image*',
+      path: nextConfig.images.path || '/_next/image',
+    })
+
+    manifest.layers.push({
+      name: 'https://ipx-edge-function-layer.netlify.app/mod.ts',
+      flag: 'ipx-edge-function-layer-url',
     })
   } else {
     console.log(

packages/runtime/src/templates/edge/imageconfig.json

@@ -0,0 +1,3 @@
+{
+  "formats": ["webp"]
+}

packages/runtime/src/templates/edge/ipx.ts

@@ -1,73 +1,5 @@
-import { Accepts } from 'https://deno.land/x/accepts@2.1.1/mod.ts'
-import type { Context } from 'https://edge.netlify.com'
-// Available at build time
-import imageconfig from './imageconfig.json' assert { type: 'json' }
-
-const defaultFormat = 'webp'
-
-interface ImageConfig extends Record<string, unknown> {
-  formats?: string[]
-}
-
-// Checks if a URL param is numeric
-const isNumeric = (value: string | null) => Number(value).toString() === value
-
-/**
- * Implement content negotiation for images
- */
-
-// deno-lint-ignore require-await
-const handler = async (req: Request, context: Context) => {
-  const { searchParams } = new URL(req.url)
-  const accept = new Accepts(req.headers)
-  const { formats = [defaultFormat] } = imageconfig as ImageConfig
-  if (formats.length === 0) {
-    formats.push(defaultFormat)
-  }
-  let type = accept.types(formats) || defaultFormat
-  if (Array.isArray(type)) {
-    type = type[0]
-  }
-
-  const source = searchParams.get('url')
-  const width = searchParams.get('w')
-  const quality = searchParams.get('q') ?? '75'
+import { getHandler } from 'https://ipx-edge-function-layer.netlify.app/mod.ts'
 
-  const errors: Array<string> = []
-
-  if (!source) {
-    errors.push('Missing "url" parameter')
-  } else if (!source.startsWith('http') && !source.startsWith('/')) {
-    errors.push('The "url" parameter must be a valid URL or path')
-  }
-
-  if (!width) {
-    errors.push('Missing "w" parameter')
-  } else if (!isNumeric(width)) {
-    errors.push('Invalid "w" parameter')
-  }
-
-  if (!isNumeric(quality)) {
-    errors.push('Invalid "q" parameter')
-  }
-
-  if (!source || errors.length > 0) {
-    return new Response(`Invalid request: \n${errors.join('\n')}`, {
-      status: 400,
-    })
-  }
-
-  const modifiers = [`w_${width}`, `q_${quality}`]
-
-  if (type) {
-    if (type.includes('/')) {
-      // If this is a mimetype, strip "image/"
-      type = type.split('/')[1]
-    }
-    modifiers.push(`f_${type}`)
-  }
-  const target = `/_ipx/${modifiers.join(',')}/${encodeURIComponent(source)}`
-  return context.rewrite(target)
-}
+import imageconfig from './imageconfig.json' assert { type: 'json' }
 
-export default handler
+export default getHandler({ formats: imageconfig?.formats })