feat(@astrojs/netlify): Add on-demand builders Netlify functions (#5874)

* Add on-demand builders option

* chore: add changeset

* docs: add documentation in configuration section

* Update packages/integrations/netlify/README.md

Co-authored-by: Sarah Rainsberger <sarah@rainsberger.ca>

* Update packages/integrations/netlify/README.md

Co-authored-by: Sarah Rainsberger <sarah@rainsberger.ca>

* Update packages/integrations/netlify/README.md

Co-authored-by: Sarah Rainsberger <sarah@rainsberger.ca>

* Update .changeset/twenty-pans-agree.md

Co-authored-by: Sarah Rainsberger <sarah@rainsberger.ca>

---------

Co-authored-by: Sarah Rainsberger <sarah@rainsberger.ca>

Author: juanmiguelguerrero

packages/integrations/netlify/README.md

@@ -117,6 +117,27 @@ And then point to the dist in your `netlify.toml`:
 directory = "dist/functions"
 ```
 
+### builders
+
+[Netlify On-demand Builders](https://docs.netlify.com/configure-builds/on-demand-builders/) are serverless functions used to build and cache page content on Netlify’s Edge CDN. You can enable these functions with the `builders` option:
+
+```js
+// astro.config.mjs
+import { defineConfig } from 'astro/config';
+import netlify from '@astrojs/netlify/functions';
+
+export default defineConfig({
+  output: 'server',
+  adapter: netlify({
+    builders: true
+  }),
+});
+```
+
+On-demand Builders are only available with the `@astrojs/netlify/functions` adapter and are not compatible with Edge Functions.
+
+
+
 ### binaryMediaTypes
 
 > This option is only needed for the Functions adapter and is not needed for Edge Functions.

packages/integrations/netlify/src/integration-edge-functions.ts

@@ -163,7 +163,7 @@ export function netlifyEdgeFunctions({ dist }: NetlifyEdgeFunctionsOptions = {})
 			'astro:build:done': async ({ routes, dir }) => {
 				await bundleServerEntry(_buildConfig, _vite);
 				await createEdgeManifest(routes, entryFile, _config.root);
-				await createRedirects(_config, routes, dir, entryFile, true);
+				await createRedirects(_config, routes, dir, entryFile, 'edge-functions');
 			},
 		},
 	};

packages/integrations/netlify/src/integration-functions.ts

@@ -13,11 +13,13 @@ export function getAdapter(args: Args = {}): AstroAdapter {
 
 interface NetlifyFunctionsOptions {
 	dist?: URL;
+	builders?: boolean;
 	binaryMediaTypes?: string[];
 }
 
 function netlifyFunctions({
 	dist,
+	builders,
 	binaryMediaTypes,
 }: NetlifyFunctionsOptions = {}): AstroIntegration {
 	let _config: AstroConfig;
@@ -36,7 +38,7 @@ function netlifyFunctions({
 				});
 			},
 			'astro:config:done': ({ config, setAdapter }) => {
-				setAdapter(getAdapter({ binaryMediaTypes }));
+				setAdapter(getAdapter({ binaryMediaTypes, builders }));
 				_config = config;
 				entryFile = config.build.serverEntry.replace(/\.m?js/, '');
 
@@ -48,7 +50,8 @@ function netlifyFunctions({
 				}
 			},
 			'astro:build:done': async ({ routes, dir }) => {
-				await createRedirects(_config, routes, dir, entryFile, false);
+				const type = builders ? 'builders' : 'functions'
+				await createRedirects(_config, routes, dir, entryFile, type);
 			},
 		},
 	};

packages/integrations/netlify/src/netlify-functions.ts

@@ -1,5 +1,5 @@
 import { polyfill } from '@astrojs/webapi';
-import type { Handler } from '@netlify/functions';
+import { builder, Handler } from '@netlify/functions';
 import { SSRManifest } from 'astro';
 import { App } from 'astro/app';
 
@@ -8,6 +8,7 @@ polyfill(globalThis, {
 });
 
 export interface Args {
+	builders?: boolean;
 	binaryMediaTypes?: string[];
 }
 
@@ -20,6 +21,7 @@ const clientAddressSymbol = Symbol.for('astro.clientAddress');
 export const createExports = (manifest: SSRManifest, args: Args) => {
 	const app = new App(manifest);
 
+	const builders = args.builders ?? false;
 	const binaryMediaTypes = args.binaryMediaTypes ?? [];
 	const knownBinaryMediaTypes = new Set([
 		'audio/3gpp',
@@ -53,7 +55,7 @@ export const createExports = (manifest: SSRManifest, args: Args) => {
 		...binaryMediaTypes,
 	]);
 
-	const handler: Handler = async (event) => {
+	const myHandler: Handler = async (event) => {
 		const { httpMethod, headers, rawUrl, body: requestBody, isBase64Encoded } = event;
 		const init: RequestInit = {
 			method: httpMethod,
@@ -143,6 +145,8 @@ export const createExports = (manifest: SSRManifest, args: Args) => {
 		return fnResponse;
 	};
 
+	const handler = builders ? builder(myHandler) : myHandler
+
 	return { handler };
 };
 

packages/integrations/netlify/src/shared.ts

@@ -14,10 +14,10 @@ export async function createRedirects(
 	routes: RouteData[],
 	dir: URL,
 	entryFile: string,
-	edge: boolean
+	type: 'functions' | 'edge-functions' | 'builders'
 ) {
 	const _redirectsURL = new URL('./_redirects', dir);
-	const kind = edge ? 'edge-functions' : 'functions';
+	const kind = type ?? 'functions';
 
 	const definitions: RedirectDefinition[] = [];