feat: add support for other markdown file extensions

.changeset/many-rockets-admire.md

@@ -0,0 +1,11 @@
+---
+'astro': minor
+'@astrojs/rss': patch
+---
+
+Add support for markdown files with the following extensions:
+- `.markdown`
+- `.mdown`
+- `.mkdn`
+- `.mkd`
+- `.mdwn`

packages/astro-rss/src/index.ts

@@ -17,7 +17,7 @@ type RSSOptions = {
 	/**
 	 * List of RSS feed items to render. Accepts either:
 	 * a) list of RSSFeedItems
-	 * b) import.meta.glob result. You can only glob ".md" files within src/pages/ when using this method!
+	 * b) import.meta.glob result. You can only glob ".md" (or alternative extensions for markdown files like ".markdown") files within src/pages/ when using this method!
 	 */
 	items: RSSFeedItem[] | GlobResult;
 	/** Specify arbitrary metadata on opening <xml> tag */
@@ -58,7 +58,7 @@ function mapGlobResult(items: GlobResult): Promise<RSSFeedItem[]> {
 			const { url, frontmatter } = await getInfo();
 			if (url === undefined || url === null) {
 				throw new Error(
-					`[RSS] When passing an import.meta.glob result directly, you can only glob ".md" files within /pages! Consider mapping the result to an array of RSSFeedItems. See the RSS docs for usage examples: https://docs.astro.build/en/guides/rss/#2-list-of-rss-feed-objects`
+					`[RSS] When passing an import.meta.glob result directly, you can only glob ".md" (or alternative extensions for markdown files like ".markdown") files within /pages! Consider mapping the result to an array of RSSFeedItems. See the RSS docs for usage examples: https://docs.astro.build/en/guides/rss/#2-list-of-rss-feed-objects`
 				);
 			}
 			if (!Boolean(frontmatter.title) || !Boolean(frontmatter.pubDate)) {

packages/astro-rss/test/rss.test.js

@@ -198,7 +198,11 @@ describe('rss', () => {
 				});
 				chai.expect(false).to.equal(true, 'Should have errored');
 			} catch (err) {
-				chai.expect(err.message).to.contain('you can only glob ".md" files within /pages');
+				chai
+					.expect(err.message)
+					.to.contain(
+						'you can only glob ".md" (or alternative extensions for markdown files like ".markdown") files within /pages'
+					);
 			}
 		});
 	});

packages/astro/client-base.d.ts

@@ -1,19 +1,106 @@
 /// <reference path="./import-meta.d.ts" />
 
+type MD = import('./dist/@types/astro').MarkdownInstance<Record<string, any>>;
+interface ExportedMarkdownModuleEntities {
+	frontmatter: MD['frontmatter'];
+	file: MD['file'];
+	url: MD['url'];
+	getHeadings: MD['getHeadings'];
+	/** @deprecated Renamed to `getHeadings()` */
+	getHeaders: () => void;
+	Content: MD['Content'];
+	rawContent: MD['rawContent'];
+	compiledContent: MD['compiledContent'];
+	load: MD['default'];
+}
+
 declare module '*.md' {
-	type MD = import('./dist/@types/astro').MarkdownInstance<Record<string, any>>;
+	const { load }: ExportedMarkdownModuleEntities;
+	export const {
+		frontmatter,
+		file,
+		url,
+		getHeadings,
+		getHeaders,
+		Content,
+		rawContent,
+		compiledContent,
+	}: ExportedMarkdownModuleEntities;
+	export default load;
+}
 
-	export const frontmatter: MD['frontmatter'];
-	export const file: MD['file'];
-	export const url: MD['url'];
-	export const getHeadings: MD['getHeadings'];
-	/** @deprecated Renamed to `getHeadings()` */
-	export const getHeaders: () => void;
-	export const Content: MD['Content'];
-	export const rawContent: MD['rawContent'];
-	export const compiledContent: MD['compiledContent'];
+declare module '*.markdown' {
+	const { load }: ExportedMarkdownModuleEntities;
+	export const {
+		frontmatter,
+		file,
+		url,
+		getHeadings,
+		getHeaders,
+		Content,
+		rawContent,
+		compiledContent,
+	}: ExportedMarkdownModuleEntities;
+	export default load;
+}
+
+declare module '*.mkdn' {
+	const { load }: ExportedMarkdownModuleEntities;
+	export const {
+		frontmatter,
+		file,
+		url,
+		getHeadings,
+		getHeaders,
+		Content,
+		rawContent,
+		compiledContent,
+	}: ExportedMarkdownModuleEntities;
+	export default load;
+}
+
+declare module '*.mkd' {
+	const { load }: ExportedMarkdownModuleEntities;
+	export const {
+		frontmatter,
+		file,
+		url,
+		getHeadings,
+		getHeaders,
+		Content,
+		rawContent,
+		compiledContent,
+	}: ExportedMarkdownModuleEntities;
+	export default load;
+}
+
+declare module '*.mdwn' {
+	const { load }: ExportedMarkdownModuleEntities;
+	export const {
+		frontmatter,
+		file,
+		url,
+		getHeadings,
+		getHeaders,
+		Content,
+		rawContent,
+		compiledContent,
+	}: ExportedMarkdownModuleEntities;
+	export default load;
+}
 
-	const load: MD['default'];
+declare module '*.mdown' {
+	const { load }: ExportedMarkdownModuleEntities;
+	export const {
+		frontmatter,
+		file,
+		url,
+		getHeadings,
+		getHeaders,
+		Content,
+		rawContent,
+		compiledContent,
+	}: ExportedMarkdownModuleEntities;
 	export default load;
 }
 

packages/astro/src/@types/astro.ts

@@ -1,3 +1,4 @@
+import { SUPPORTED_MARKDOWN_FILE_EXTENSIONS } from './../core/constants.js';
 import type {
 	MarkdownHeading,
 	MarkdownMetadata,
@@ -246,6 +247,9 @@ export interface AstroGlobal<Props extends Record<string, any> = Record<string,
 	};
 }
 
+/** Union type of supported markdown file extensions */
+type MarkdowFileExtension = typeof SUPPORTED_MARKDOWN_FILE_EXTENSIONS[number];
+
 export interface AstroGlobalPartial {
 	/**
 	 * @deprecated since version 0.24. See the {@link https://astro.build/deprecated/resolve upgrade guide} for more details.
@@ -264,7 +268,9 @@ export interface AstroGlobalPartial {
 	 * [Astro reference](https://docs.astro.build/en/reference/api-reference/#astroglob)
 	 */
 	glob(globStr: `${any}.astro`): Promise<AstroInstance[]>;
-	glob<T extends Record<string, any>>(globStr: `${any}.md`): Promise<MarkdownInstance<T>[]>;
+	glob<T extends Record<string, any>>(
+		globStr: `${any}${MarkdowFileExtension}`
+	): Promise<MarkdownInstance<T>[]>;
 	glob<T extends Record<string, any>>(globStr: `${any}.mdx`): Promise<MDXInstance<T>[]>;
 	glob<T extends Record<string, any>>(globStr: string): Promise<T[]>;
 	/**
@@ -868,7 +874,7 @@ export interface AstroUserConfig {
 		 * @default `false`
 		 * @version 1.0.0-rc.1
 		 * @description
-		 * Enable Astro's pre-v1.0 support for components and JSX expressions in `.md` Markdown files.
+		 * Enable Astro's pre-v1.0 support for components and JSX expressions in `.md` (and alternative extensions for markdown files like ".markdown") Markdown files.
 		 * In Astro `1.0.0-rc`, this original behavior was removed as the default, in favor of our new [MDX integration](/en/guides/integrations-guide/mdx/).
 		 *
 		 * To enable this behavior, set `legacy.astroFlavoredMarkdown` to `true` in your [`astro.config.mjs` configuration file](/en/guides/configuring-astro/#the-astro-config-file).

packages/astro/src/core/build/graph.ts

@@ -32,7 +32,7 @@ export function moduleIsTopLevelPage(info: ModuleInfo): boolean {
 }
 
 // This function walks the dependency graph, going up until it finds a page component.
-// This could be a .astro page or a .md page.
+// This could be a .astro page, a .markdown or a .md (or really any file extension for markdown files) page.
 export function* getTopLevelPages(
 	id: string,
 	ctx: { getModuleInfo: GetModuleInfo }

packages/astro/src/core/config/settings.ts

@@ -1,3 +1,4 @@
+import { SUPPORTED_MARKDOWN_FILE_EXTENSIONS } from './../constants.js';
 import type { AstroConfig, AstroSettings } from '../../@types/astro';
 
 import jsxRenderer from '../../jsx/renderer.js';
@@ -13,7 +14,7 @@ export function createSettings(config: AstroConfig, cwd?: string): AstroSettings
 
 		adapter: undefined,
 		injectedRoutes: [],
-		pageExtensions: ['.astro', '.md', '.html'],
+		pageExtensions: ['.astro', '.html', ...SUPPORTED_MARKDOWN_FILE_EXTENSIONS],
 		renderers: [jsxRenderer],
 		scripts: [],
 		watchFiles: tsconfig?.exists ? [tsconfig.path, ...tsconfig.extendedPaths] : [],

packages/astro/src/core/constants.ts

@@ -1,2 +1,12 @@
 // process.env.PACKAGE_VERSION is injected when we build and publish the astro package.
 export const ASTRO_VERSION = process.env.PACKAGE_VERSION ?? 'development';
+
+// possible extensions for markdown files
+export const SUPPORTED_MARKDOWN_FILE_EXTENSIONS = [
+	'.markdown',
+	'.mdown',
+	'.mkdn',
+	'.mkd',
+	'.mdwn',
+	'.md',
+] as const;

packages/astro/src/core/render/dev/vite.ts

@@ -1,13 +1,14 @@
 import npath from 'path';
 import vite from 'vite';
+import { SUPPORTED_MARKDOWN_FILE_EXTENSIONS } from '../../constants.js';
 import { unwrapId } from '../../util.js';
 import { STYLE_EXTENSIONS } from '../util.js';
 
 /**
  * List of file extensions signalling we can (and should) SSR ahead-of-time
  * See usage below
  */
-const fileExtensionsToSSR = new Set(['.astro', '.md']);
+const fileExtensionsToSSR = new Set(['.astro', ...SUPPORTED_MARKDOWN_FILE_EXTENSIONS]);
 
 const STRIP_QUERY_PARAMS_REGEX = /\?.*$/;
 

packages/astro/src/core/routing/manifest/create.ts

@@ -17,6 +17,7 @@ import { warn } from '../../logger/core.js';
 import { removeLeadingForwardSlash } from '../../path.js';
 import { resolvePages } from '../../util.js';
 import { getRouteGenerator } from './generator.js';
+import { SUPPORTED_MARKDOWN_FILE_EXTENSIONS } from '../../constants.js';
 const require = createRequire(import.meta.url);
 
 interface Item {
@@ -206,7 +207,11 @@ export function createRouteManifest(
 ): ManifestData {
 	const components: string[] = [];
 	const routes: RouteData[] = [];
-	const validPageExtensions: Set<string> = new Set(['.astro', '.md', ...settings.pageExtensions]);
+	const validPageExtensions: Set<string> = new Set([
+		'.astro',
+		...SUPPORTED_MARKDOWN_FILE_EXTENSIONS,
+		...settings.pageExtensions,
+	]);
 	const validEndpointExtensions: Set<string> = new Set(['.js', '.ts']);
 
 	function walk(dir: string, parentSegments: RoutePart[][], parentParams: string[]) {

packages/astro/src/core/util.ts

@@ -7,6 +7,7 @@ import { fileURLToPath, pathToFileURL } from 'url';
 import { ErrorPayload, normalizePath, ViteDevServer } from 'vite';
 import type { AstroConfig, AstroSettings, RouteType } from '../@types/astro';
 import { prependForwardSlash, removeTrailingForwardSlash } from './path.js';
+import { SUPPORTED_MARKDOWN_FILE_EXTENSIONS } from './constants.js';
 
 /** Returns true if argument is an object of any prototype/class (but not null). */
 export function isObject(value: unknown): value is Record<string, any> {
@@ -17,6 +18,23 @@ export function isObject(value: unknown): value is Record<string, any> {
 export function isURL(value: unknown): value is URL {
 	return Object.prototype.toString.call(value) === '[object URL]';
 }
+/** Check if a file is a markdown file based on its extension */
+export function isMarkdownFile(
+	fileId: string,
+	option: { criteria: 'endsWith' | 'includes'; suffix?: string }
+): boolean {
+	const _suffix = option.suffix ?? '';
+	if (option.criteria === 'endsWith') {
+		for (let markdownFileExtension of SUPPORTED_MARKDOWN_FILE_EXTENSIONS) {
+			if (fileId.endsWith(`${markdownFileExtension}${_suffix}`)) return true;
+		}
+		return false;
+	}
+	for (let markdownFileExtension of SUPPORTED_MARKDOWN_FILE_EXTENSIONS) {
+		if (fileId.includes(`${markdownFileExtension}${_suffix}`)) return true;
+	}
+	return false;
+}
 
 /** Wraps an object in an array. If an array is passed, ignore it. */
 export function arraify<T>(target: T | T[]): T[] {

packages/astro/src/vite-plugin-astro-postprocess/index.ts

@@ -4,6 +4,7 @@ import type { NodePath } from 'ast-types/lib/node-path';
 import { parse, print, types, visit } from 'recast';
 import type { Plugin } from 'vite';
 import type { AstroSettings } from '../@types/astro';
+import { isMarkdownFile } from '../core/util.js';
 
 // Check for `Astro.glob()`. Be very forgiving of whitespace. False positives are okay.
 const ASTRO_GLOB_REGEX = /Astro2?\s*\.\s*glob\s*\(/;
@@ -16,8 +17,8 @@ export default function astro(_opts: AstroPluginOptions): Plugin {
 	return {
 		name: 'astro:postprocess',
 		async transform(code, id) {
-			// Currently only supported in ".astro" & ".md" files
-			if (!id.endsWith('.astro') && !id.endsWith('.md')) {
+			// Currently only supported in ".astro" and ".md" (or any alternative markdown file extension like `.markdown`) files
+			if (!id.endsWith('.astro') && !isMarkdownFile(id, { criteria: 'endsWith' })) {
 				return null;
 			}
 

packages/astro/src/vite-plugin-jsx/index.ts

@@ -11,7 +11,7 @@ import esbuild from 'esbuild';
 import * as colors from 'kleur/colors';
 import path from 'path';
 import { error } from '../core/logger/core.js';
-import { parseNpmName } from '../core/util.js';
+import { isMarkdownFile, parseNpmName } from '../core/util.js';
 import tagExportsPlugin from './tag.js';
 
 type FixedCompilerOptions = TsConfigJson.CompilerOptions & {
@@ -193,7 +193,7 @@ export default function jsx({ settings, logging }: AstroPluginJSXOptions): Plugi
 
 			const { mode } = viteConfig;
 			// Shortcut: only use Astro renderer for MD and MDX files
-			if (id.includes('.mdx') || id.includes('.md')) {
+			if (id.includes('.mdx') || isMarkdownFile(id, { criteria: 'includes' })) {
 				const { code: jsxCode } = await esbuild.transform(code, {
 					loader: getEsbuildLoader(path.extname(id)) as esbuild.Loader,
 					jsx: 'preserve',

packages/astro/src/vite-plugin-markdown-legacy/index.ts

@@ -10,6 +10,7 @@ import { pagesVirtualModuleId } from '../core/app/index.js';
 import { cachedCompilation, CompileProps } from '../core/compile/index.js';
 import { collectErrorMetadata } from '../core/errors.js';
 import type { LogOptions } from '../core/logger/core.js';
+import { isMarkdownFile } from '../core/util.js';
 import type { PluginMetadata as AstroPluginMetadata } from '../vite-plugin-astro/types';
 import { getFileInfo } from '../vite-plugin-utils/index.js';
 import {
@@ -79,18 +80,18 @@ export default function markdown({ settings }: AstroPluginOptions): Plugin {
 			styleTransformer.viteDevServer = server;
 		},
 		async resolveId(id, importer, options) {
-			// Resolve any .md files with the `?content` cache buster. This should only come from
+			// Resolve any .md (or alternative extensions of markdown files like .markdown) files with the `?content` cache buster. This should only come from
 			// an already-resolved JS module wrapper. Needed to prevent infinite loops in Vite.
 			// Unclear if this is expected or if cache busting is just working around a Vite bug.
-			if (id.endsWith(`.md${MARKDOWN_CONTENT_FLAG}`)) {
+			if (isMarkdownFile(id, { criteria: 'endsWith', suffix: MARKDOWN_CONTENT_FLAG })) {
 				const resolvedId = await this.resolve(id, importer, { skipSelf: true, ...options });
 				return resolvedId?.id.replace(MARKDOWN_CONTENT_FLAG, '');
 			}
 			// If the markdown file is imported from another file via ESM, resolve a JS representation
 			// that defers the markdown -> HTML rendering until it is needed. This is especially useful
 			// when fetching and then filtering many markdown files, like with import.meta.glob() or Astro.glob().
 			// Otherwise, resolve directly to the actual component.
-			if (id.endsWith('.md') && !isRootImport(importer)) {
+			if (isMarkdownFile(id, { criteria: 'endsWith' }) && !isRootImport(importer)) {
 				const resolvedId = await this.resolve(id, importer, { skipSelf: true, ...options });
 				if (resolvedId) {
 					return resolvedId.id + MARKDOWN_IMPORT_FLAG;
@@ -103,7 +104,7 @@ export default function markdown({ settings }: AstroPluginOptions): Plugin {
 			// A markdown file has been imported via ESM!
 			// Return the file's JS representation, including all Markdown
 			// frontmatter and a deferred `import() of the compiled markdown content.
-			if (id.endsWith(`.md${MARKDOWN_IMPORT_FLAG}`)) {
+			if (isMarkdownFile(id, { criteria: 'endsWith', suffix: MARKDOWN_IMPORT_FLAG })) {
 				const { fileId, fileUrl } = getFileInfo(id, config);
 
 				const source = await fs.promises.readFile(fileId, 'utf8');
@@ -143,7 +144,7 @@ export default function markdown({ settings }: AstroPluginOptions): Plugin {
 			// A markdown file is being rendered! This markdown file was either imported
 			// directly as a page in Vite, or it was a deferred render from a JS module.
 			// This returns the compiled markdown -> astro component that renders to HTML.
-			if (id.endsWith('.md')) {
+			if (isMarkdownFile(id, { criteria: 'endsWith' })) {
 				const filename = normalizeFilename(id);
 				const source = await fs.promises.readFile(filename, 'utf8');
 				const renderOpts = config.markdown;