Adapters v0 (#2855)

* Adapter v0

* Finalizing adapters

* Update the lockfile

* Add the default adapter after config setup is called

* Create the default adapter in config:done

* Fix lint error

* Remove unused callConfigSetup

* remove unused export

* Use a test adapter to test SSR

* Adds a changeset

* Updated based on feedback

* Updated the lockfile

* Only throw if set to a different adapter

* Clean up outdated comments

* Move the adapter to an  config option

* Make adapter optional

* Update the docs/changeset to reflect config API change

* Clarify regular Node usage

2 files changed, 68 insertions, 0 deletions

diff --git a/packages/integrations/node/src/index.ts b/packages/integrations/node/src/index.ts
new file mode 100644
index 000000000..903d5b1cc
--- /dev/null
+++ b/packages/integrations/node/src/index.ts
@@ -0,0 +1,20 @@
+import type { AstroAdapter, AstroIntegration } from 'astro';
+
+export function getAdapter(): AstroAdapter {
+	return {
+		name: '@astrojs/node',
+		serverEntrypoint: '@astrojs/node/server.js',
+		exports: ['handler'],
+	};
+}
+
+export default function createIntegration(): AstroIntegration {
+	return {
+		name: '@astrojs/node',
+		hooks: {
+			'astro:config:done': ({ setAdapter }) => {
+				setAdapter(getAdapter());
+			}
+		}
+	};
+}
diff --git a/packages/integrations/node/src/server.ts b/packages/integrations/node/src/server.ts
new file mode 100644
index 000000000..791dc58b2
--- /dev/null
+++ b/packages/integrations/node/src/server.ts
@@ -0,0 +1,48 @@
+import type { SSRManifest } from 'astro';
+import type { IncomingMessage, ServerResponse } from 'http';
+import { NodeApp } from 'astro/app/node';
+import { polyfill } from '@astrojs/webapi';
+
+polyfill(globalThis, {
+	exclude: 'window document'
+});
+
+export function createExports(manifest: SSRManifest) {
+	const app = new NodeApp(manifest, new URL(import.meta.url));
+	return {
+		async handler(req: IncomingMessage, res: ServerResponse, next?: (err?: unknown) => void) {
+			const route = app.match(req);
+
+			if(route) {
+				try {
+					const response = await app.render(req);
+					await writeWebResponse(res, response);
+				} catch(err: unknown) {
+					if(next) {
+						next(err);
+					} else {
+						throw err;
+					}
+				}
+			} else if(next) {
+				return next();
+			}
+		}
+	}
+}
+
+async function writeWebResponse(res: ServerResponse, webResponse: Response) {
+	const { status, headers, body } = webResponse;
+	res.writeHead(status, Object.fromEntries(headers.entries()));
+	if (body) {
+		const reader = body.getReader();
+		while (true) {
+			const { done, value } = await reader.read();
+			if (done) break;
+			if (value) {
+				res.write(value);
+			}
+		}
+	}
+	res.end();
+}