refactor: move renderers to their own plugin (#7166)

.changeset/early-cars-kick.md

@@ -0,0 +1,5 @@
+---
+'astro': patch
+---
+
+Move generation of renderers code into their own file

packages/astro/src/core/build/plugins/index.ts

@@ -11,12 +11,14 @@ import { pluginMiddleware } from './plugin-middleware.js';
 import { pluginPages } from './plugin-pages.js';
 import { pluginPrerender } from './plugin-prerender.js';
 import { pluginSSR } from './plugin-ssr.js';
+import { pluginRenderers } from './plugin-renderers.js';
 
 export function registerAllPlugins({ internals, options, register }: AstroBuildPluginContainer) {
 	register(pluginComponentEntry(internals));
 	register(pluginAliasResolve(internals));
 	register(pluginAnalyzer(internals));
 	register(pluginInternals(internals));
+	register(pluginRenderers(options, internals));
 	register(pluginMiddleware(options, internals));
 	register(pluginPages(options, internals));
 	register(pluginCSS(options, internals));

packages/astro/src/core/build/plugins/plugin-pages.ts

@@ -5,6 +5,7 @@ import { eachPageData, type BuildInternals } from '../internal.js';
 import type { AstroBuildPlugin } from '../plugin';
 import type { StaticBuildOptions } from '../types';
 import { MIDDLEWARE_MODULE_ID } from './plugin-middleware.js';
+import { RENDERERS_MODULE_ID } from './plugin-renderers.js';
 
 function vitePluginPages(opts: StaticBuildOptions, internals: BuildInternals): VitePlugin {
 	return {
@@ -25,8 +26,12 @@ function vitePluginPages(opts: StaticBuildOptions, internals: BuildInternals): V
 		async load(id) {
 			if (id === resolvedPagesVirtualModuleId) {
 				let importMap = '';
-				let imports = [];
+				const imports: string[] = [];
+				const exports: string[] = [];
+				const content: string[] = [];
 				let i = 0;
+				imports.push(`import { renderers } from "${RENDERERS_MODULE_ID}";`);
+				exports.push(`export { renderers };`);
 				for (const pageData of eachPageData(internals)) {
 					const variable = `_page${i}`;
 					imports.push(
@@ -36,31 +41,14 @@ function vitePluginPages(opts: StaticBuildOptions, internals: BuildInternals): V
 					i++;
 				}
 
-				i = 0;
-				let rendererItems = '';
-				for (const renderer of opts.settings.renderers) {
-					const variable = `_renderer${i}`;
-					// Use unshift so that renderers are imported before user code, in case they set globals
-					// that user code depends on.
-					imports.unshift(`import ${variable} from '${renderer.serverEntrypoint}';`);
-					rendererItems += `Object.assign(${JSON.stringify(renderer)}, { ssr: ${variable} }),`;
-					i++;
+				if (opts.settings.config.experimental.middleware) {
+					imports.push(`import * as _middleware from "${MIDDLEWARE_MODULE_ID}";`);
+					exports.push(`export const middleware = _middleware;`);
 				}
 
-				const def = `${imports.join('\n')}
-
-${
-	opts.settings.config.experimental.middleware
-		? `import * as _middleware from "${MIDDLEWARE_MODULE_ID}";`
-		: ''
-}
-
-export const pageMap = new Map([${importMap}]);
-export const renderers = [${rendererItems}];
-${opts.settings.config.experimental.middleware ? `export const middleware = _middleware;` : ''}
-`;
+				content.push(`export const pageMap = new Map([${importMap}]);`);
 
-				return def;
+				return `${imports.join('\n')}${content.join('\n')}${exports.join('\n')}`;
 			}
 		},
 	};

packages/astro/src/core/build/plugins/plugin-renderers.ts

@@ -0,0 +1,66 @@
+import type { Plugin as VitePlugin } from 'vite';
+import { addRollupInput } from '../add-rollup-input.js';
+import type { BuildInternals } from '../internal.js';
+import type { AstroBuildPlugin } from '../plugin';
+import type { StaticBuildOptions } from '../types';
+
+export const RENDERERS_MODULE_ID = '@astro-renderers';
+export const RESOLVED_RENDERERS_MODULE_ID = `\0${RENDERERS_MODULE_ID}`;
+
+let inputs: Set<string> = new Set();
+export function vitePluginRenderers(
+	opts: StaticBuildOptions,
+	_internals: BuildInternals
+): VitePlugin {
+	return {
+		name: '@astro/plugin-renderers',
+
+		options(options) {
+			return addRollupInput(options, [RENDERERS_MODULE_ID]);
+		},
+
+		resolveId(id) {
+			if (id === RENDERERS_MODULE_ID) {
+				return RESOLVED_RENDERERS_MODULE_ID;
+			}
+		},
+
+		async load(id) {
+			if (id === RESOLVED_RENDERERS_MODULE_ID) {
+				if (opts.settings.renderers.length > 0) {
+					const imports: string[] = [];
+					const exports: string[] = [];
+					let i = 0;
+					let rendererItems = '';
+
+					for (const renderer of opts.settings.renderers) {
+						const variable = `_renderer${i}`;
+						imports.push(`import ${variable} from '${renderer.serverEntrypoint}';`);
+						rendererItems += `Object.assign(${JSON.stringify(renderer)}, { ssr: ${variable} }),`;
+						i++;
+					}
+
+					exports.push(`export const renderers = [${rendererItems}];`);
+
+					return `${imports.join('\n')}\n${exports.join('\n')}`;
+				}
+			}
+		},
+	};
+}
+
+export function pluginRenderers(
+	opts: StaticBuildOptions,
+	internals: BuildInternals
+): AstroBuildPlugin {
+	return {
+		build: 'ssr',
+		hooks: {
+			'build:before': () => {
+				return {
+					vitePlugin: vitePluginRenderers(opts, internals),
+				};
+			},
+		},
+	};
+}

packages/astro/src/core/build/plugins/plugin-ssr.ts

@@ -15,6 +15,7 @@ import { addRollupInput } from '../add-rollup-input.js';
 import { getOutFile, getOutFolder } from '../common.js';
 import { cssOrder, mergeInlineCss, type BuildInternals } from '../internal.js';
 import type { AstroBuildPlugin } from '../plugin';
+import { RENDERERS_MODULE_ID } from './plugin-renderers.js';
 
 export const virtualModuleId = '@astrojs-ssr-virtual-entry';
 const resolvedVirtualModuleId = '\0' + virtualModuleId;
@@ -44,6 +45,7 @@ function vitePluginSSR(
 					middleware = 'middleware: _main.middleware';
 				}
 				return `import * as adapter from '${adapter.serverEntrypoint}';
+import { renderers } from '${RENDERERS_MODULE_ID}'; 
 import * as _main from '${pagesVirtualModuleId}';
 import { deserializeManifest as _deserializeManifest } from 'astro/app';
 import { _privateSetManifestDontUseThis } from 'astro:ssr-manifest';

packages/astro/src/core/build/static-build.ts

@@ -28,6 +28,7 @@ import { registerAllPlugins } from './plugins/index.js';
 import { RESOLVED_MIDDLEWARE_MODULE_ID } from './plugins/plugin-middleware.js';
 import type { PageBuildData, StaticBuildOptions } from './types';
 import { getTimeStat } from './util.js';
+import { RESOLVED_RENDERERS_MODULE_ID } from './plugins/plugin-renderers.js';
 
 export async function viteBuild(opts: StaticBuildOptions) {
 	const { allPages, settings } = opts;
@@ -175,6 +176,8 @@ async function ssrBuild(
 							return opts.buildConfig.serverEntry;
 						} else if (chunkInfo.facadeModuleId === RESOLVED_MIDDLEWARE_MODULE_ID) {
 							return 'middleware.mjs';
+						} else if (chunkInfo.facadeModuleId === RESOLVED_RENDERERS_MODULE_ID) {
+							return 'renderers.mjs';
 						} else {
 							return '[name].mjs';
 						}

packages/astro/test/sourcemap.test.js

@@ -16,7 +16,7 @@ describe('Sourcemap', async () => {
 	});
 
 	it('Builds non-empty sourcemap', async () => {
-		const map = await fixture.readFile('entry.mjs.map');
+		const map = await fixture.readFile('renderers.mjs.map');
 		expect(map).to.not.include('"sources":[]');
 	});
 });