1 files changed, 78 insertions, 0 deletions
diff --git a/packages/integrations/netlify/src/ssr-function.ts b/packages/integrations/netlify/src/ssr-function.ts
new file mode 100644
index 000000000..5ea2e97f1
--- /dev/null
+++ b/packages/integrations/netlify/src/ssr-function.ts
@@ -0,0 +1,78 @@
+// Keep at the top
+import './polyfill.js';
+
+import type { Context } from '@netlify/functions';
+import type { SSRManifest } from 'astro';
+import { App } from 'astro/app';
+import { setGetEnv } from 'astro/env/setup';
+
+setGetEnv((key) => process.env[key]);
+
+export interface Args {
+	middlewareSecret: string;
+}
+
+const clientAddressSymbol = Symbol.for('astro.clientAddress');
+
+export const createExports = (manifest: SSRManifest, { middlewareSecret }: Args) => {
+	const app = new App(manifest);
+
+	function createHandler(integrationConfig: {
+		cacheOnDemandPages: boolean;
+		notFoundContent?: string;
+	}) {
+		return async function handler(request: Request, context: Context) {
+			const routeData = app.match(request);
+			if (!routeData && typeof integrationConfig.notFoundContent !== 'undefined') {
+				return new Response(integrationConfig.notFoundContent, {
+					status: 404,
+					headers: { 'Content-Type': 'text/html; charset=utf-8' },
+				});
+			}
+
+			Reflect.set(request, clientAddressSymbol, context.ip);
+			let locals: Record<string, unknown> = {};
+
+			const astroLocalsHeader = request.headers.get('x-astro-locals');
+			const middlewareSecretHeader = request.headers.get('x-astro-middleware-secret');
+			if (astroLocalsHeader) {
+				if (middlewareSecretHeader !== middlewareSecret) {
+					return new Response('Forbidden', { status: 403 });
+				}
+				// hide the secret from the rest of user and library code
+				request.headers.delete('x-astro-middleware-secret');
+				locals = JSON.parse(astroLocalsHeader);
+			}
+
+			locals.netlify = { context };
+
+			const response = await app.render(request, { routeData, locals });
+
+			if (app.setCookieHeaders) {
+				for (const setCookieHeader of app.setCookieHeaders(response)) {
+					response.headers.append('Set-Cookie', setCookieHeader);
+				}
+			}
+
+			if (integrationConfig.cacheOnDemandPages) {
+				const isCacheableMethod = ['GET', 'HEAD'].includes(request.method);
+
+				// any user-provided Cache-Control headers take precedence
+				const hasCacheControl = [
+					'Cache-Control',
+					'CDN-Cache-Control',
+					'Netlify-CDN-Cache-Control',
+				].some((header) => response.headers.has(header));
+
+				if (isCacheableMethod && !hasCacheControl) {
+					// caches this page for up to a year
+					response.headers.append('CDN-Cache-Control', 'public, max-age=31536000, must-revalidate');
+				}
+			}
+
+			return response;
+		};
+	}
+
+	return { default: createHandler };
+};