Merge `vercel` and `node` into main #366

1 files changed, 135 insertions, 0 deletions

diff --git a/packages/integrations/node/src/serve-static.ts b/packages/integrations/node/src/serve-static.ts
new file mode 100644
index 000000000..f4fa1fa5c
--- /dev/null
+++ b/packages/integrations/node/src/serve-static.ts
@@ -0,0 +1,135 @@
+import fs from 'node:fs';
+import type { IncomingMessage, ServerResponse } from 'node:http';
+import path from 'node:path';
+import url from 'node:url';
+import type { NodeApp } from 'astro/app/node';
+import send from 'send';
+import type { Options } from './types.js';
+
+// check for a dot followed by a extension made up of lowercase characters
+const isSubresourceRegex = /.+\.[a-z]+$/i;
+
+/**
+ * Creates a Node.js http listener for static files and prerendered pages.
+ * In standalone mode, the static handler is queried first for the static files.
+ * If one matching the request path is not found, it relegates to the SSR handler.
+ * Intended to be used only in the standalone mode.
+ */
+export function createStaticHandler(app: NodeApp, options: Options) {
+	const client = resolveClientDir(options);
+	/**
+	 * @param ssr The SSR handler to be called if the static handler does not find a matching file.
+	 */
+	return (req: IncomingMessage, res: ServerResponse, ssr: () => unknown) => {
+		if (req.url) {
+			const [urlPath, urlQuery] = req.url.split('?');
+			const filePath = path.join(client, app.removeBase(urlPath));
+
+			let pathname: string;
+			let isDirectory = false;
+			try {
+				isDirectory = fs.lstatSync(filePath).isDirectory();
+			} catch {}
+
+			const { trailingSlash = 'ignore' } = options;
+
+			const hasSlash = urlPath.endsWith('/');
+			switch (trailingSlash) {
+				case 'never':
+					// biome-ignore lint/suspicious/noDoubleEquals: <explanation>
+					if (isDirectory && urlPath != '/' && hasSlash) {
+						// biome-ignore lint/style/useTemplate: <explanation>
+						// biome-ignore lint/suspicious/noFallthroughSwitchClause: <explanation>
+						pathname = urlPath.slice(0, -1) + (urlQuery ? '?' + urlQuery : '');
+						res.statusCode = 301;
+						res.setHeader('Location', pathname);
+						return res.end();
+						// biome-ignore lint/style/noUselessElse: <explanation>
+					} else pathname = urlPath;
+				// intentionally fall through
+				case 'ignore':
+					{
+						if (isDirectory && !hasSlash) {
+							// biome-ignore lint/style/useTemplate: <explanation>
+							pathname = urlPath + '/index.html';
+						} else pathname = urlPath;
+					}
+					break;
+				case 'always':
+					// trailing slash is not added to "subresources"
+					if (!hasSlash && !isSubresourceRegex.test(urlPath)) {
+						// biome-ignore lint/style/useTemplate: <explanation>
+						pathname = urlPath + '/' + (urlQuery ? '?' + urlQuery : '');
+						res.statusCode = 301;
+						res.setHeader('Location', pathname);
+						return res.end();
+						// biome-ignore lint/style/noUselessElse: <explanation>
+					} else pathname = urlPath;
+					break;
+			}
+			// app.removeBase sometimes returns a path without a leading slash
+			pathname = prependForwardSlash(app.removeBase(pathname));
+
+			const stream = send(req, pathname, {
+				root: client,
+				dotfiles: pathname.startsWith('/.well-known/') ? 'allow' : 'deny',
+			});
+
+			let forwardError = false;
+
+			stream.on('error', (err) => {
+				if (forwardError) {
+					console.error(err.toString());
+					res.writeHead(500);
+					res.end('Internal server error');
+					return;
+				}
+				// File not found, forward to the SSR handler
+				ssr();
+			});
+			stream.on('headers', (_res: ServerResponse) => {
+				// assets in dist/_astro are hashed and should get the immutable header
+				if (pathname.startsWith(`/${options.assets}/`)) {
+					// This is the "far future" cache header, used for static files whose name includes their digest hash.
+					// 1 year (31,536,000 seconds) is convention.
+					// Taken from https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Cache-Control#immutable
+					_res.setHeader('Cache-Control', 'public, max-age=31536000, immutable');
+				}
+			});
+			stream.on('file', () => {
+				forwardError = true;
+			});
+			stream.pipe(res);
+		} else {
+			ssr();
+		}
+	};
+}
+
+function resolveClientDir(options: Options) {
+	const clientURLRaw = new URL(options.client);
+	const serverURLRaw = new URL(options.server);
+	const rel = path.relative(url.fileURLToPath(serverURLRaw), url.fileURLToPath(clientURLRaw));
+
+	// walk up the parent folders until you find the one that is the root of the server entry folder. This is how we find the client folder relatively.
+	const serverFolder = path.basename(options.server);
+	let serverEntryFolderURL = path.dirname(import.meta.url);
+	while (!serverEntryFolderURL.endsWith(serverFolder)) {
+		serverEntryFolderURL = path.dirname(serverEntryFolderURL);
+	}
+	// biome-ignore lint/style/useTemplate: <explanation>
+	const serverEntryURL = serverEntryFolderURL + '/entry.mjs';
+	const clientURL = new URL(appendForwardSlash(rel), serverEntryURL);
+	const client = url.fileURLToPath(clientURL);
+	return client;
+}
+
+function prependForwardSlash(pth: string) {
+	// biome-ignore lint/style/useTemplate: <explanation>
+	return pth.startsWith('/') ? pth : '/' + pth;
+}
+
+function appendForwardSlash(pth: string) {
+	// biome-ignore lint/style/useTemplate: <explanation>
+	return pth.endsWith('/') ? pth : pth + '/';
+}