wip: allow integrations to refresh contel layer

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

@@ -3298,6 +3298,11 @@ export interface SSRLoadedRenderer extends Pick<AstroRenderer, 'name' | 'clientE
 	ssr: SSRLoadedRendererValue;
 }
 
+export interface RefreshContentOptions {
+	loaders?: Array<string>;
+	context?: Record<string, any>;
+}
+
 export type HookParameters<
 	Hook extends keyof AstroIntegration['hooks'],
 	Fn = AstroIntegration['hooks'][Hook],
@@ -3341,6 +3346,7 @@ declare global {
 				server: vite.ViteDevServer;
 				logger: AstroIntegrationLogger;
 				toolbar: ReturnType<typeof getToolbarServerCommunicationHelpers>;
+				refreshContent?: (options: RefreshContentOptions) => Promise<void>;
 			}) => void | Promise<void>;
 			'astro:server:start': (options: {
 				address: AddressInfo;

packages/astro/src/content/content-layer.ts

@@ -3,7 +3,7 @@ import { isAbsolute } from 'node:path';
 import { fileURLToPath } from 'node:url';
 import type { FSWatcher } from 'vite';
 import xxhash from 'xxhash-wasm';
-import type { AstroSettings } from '../@types/astro.js';
+import type { AstroSettings, RefreshContentOptions } from '../@types/astro.js';
 import { AstroUserError } from '../core/errors/errors.js';
 import type { Logger } from '../core/logger/core.js';
 import {
@@ -44,12 +44,6 @@ export class ContentLayer {
 		this.#watcher = watcher;
 	}
 
-	/**
-	 * Whether the content layer is currently loading content
-	 */
-	get loading() {
-		return this.#loading;
-	}
 
 	/**
 	 * Watch for changes to the content config and trigger a sync when it changes.
@@ -71,22 +65,6 @@ export class ContentLayer {
 		this.#unsubscribe?.();
 	}
 
-	/**
-	 * Run the `load()` method of each collection's loader, which will load the data and save it in the data store.
-	 * The loader itself is responsible for deciding whether this will clear and reload the full collection, or
-	 * perform an incremental update. After the data is loaded, the data store is written to disk.
-	 */
-	async sync() {
-		if (this.#loading) {
-			return;
-		}
-		this.#loading = true;
-		try {
-			await this.#doSync();
-		} finally {
-			this.#loading = false;
-		}
-	}
 
 	async #getGenerateDigest() {
 		if (this.#generateDigest) {
@@ -108,10 +86,12 @@ export class ContentLayer {
 		collectionName,
 		loaderName = 'content',
 		parseData,
+		refreshContextData,
 	}: {
 		collectionName: string;
 		loaderName: string;
 		parseData: LoaderContext['parseData'];
+		refreshContextData?: Record<string, unknown>;
 	}): Promise<LoaderContext> {
 		return {
 			collection: collectionName,
@@ -122,10 +102,17 @@ export class ContentLayer {
 			parseData,
 			generateDigest: await this.#getGenerateDigest(),
 			watcher: this.#watcher,
+			refreshContextData
 		};
 	}
 
-	async #doSync() {
+	/**
+	 * Run the `load()` method of each collection's loader, which will load the data and save it in the data store.
+	 * The loader itself is responsible for deciding whether this will clear and reload the full collection, or
+	 * perform an incremental update. After the data is loaded, the data store is written to disk.
+	 */
+	async sync(options?: RefreshContentOptions) {
+		
 		const contentConfig = globalContentConfigObserver.get();
 		const logger = this.#logger.forkIntegrationLogger('content');
 		if (contentConfig?.status !== 'loaded') {
@@ -171,6 +158,14 @@ export class ContentLayer {
 					}
 				}
 
+				// If loaders are specified, only sync the specified loaders
+				if (
+					options?.loaders &&
+					(typeof collection.loader !== 'object' || !options.loaders.includes(collection.loader.name))
+				) {
+					return;
+				}
+
 				const collectionWithResolvedSchema = { ...collection, schema };
 
 				const parseData: LoaderContext['parseData'] = async ({ id, data, filePath = '' }) => {
@@ -204,6 +199,7 @@ export class ContentLayer {
 					collectionName: name,
 					parseData,
 					loaderName: collection.loader.name,
+					refreshContextData: options?.context
 				});
 
 				if (typeof collection.loader === 'function') {

packages/astro/src/content/loaders/types.ts

@@ -31,6 +31,9 @@ export interface LoaderContext {
 
 	/** When running in dev, this is a filesystem watcher that can be used to trigger updates */
 	watcher?: FSWatcher;
+
+	/** If the loader has been triggered by an integration, this may optionally contain extra data set by that integration */
+	refreshContextData?: Record<string, unknown>;
 }
 
 export interface Loader {

packages/astro/src/integrations/hooks.ts

@@ -12,6 +12,7 @@ import type {
 	ContentEntryType,
 	DataEntryType,
 	HookParameters,
+	RefreshContentOptions,
 	RouteData,
 	RouteOptions,
 } from '../@types/astro.js';
@@ -22,6 +23,7 @@ import { mergeConfig } from '../core/config/index.js';
 import type { AstroIntegrationLogger, Logger } from '../core/logger/core.js';
 import { isServerLikeOutput } from '../core/util.js';
 import { validateSupportedFeatures } from './features-validation.js';
+import { globalContentLayer } from '../content/content-layer.js';
 
 async function withTakingALongTimeMsg<T>({
 	name,
@@ -370,6 +372,14 @@ export async function runHookServerSetup({
 	server: ViteDevServer;
 	logger: Logger;
 }) {
+	let refreshContent: undefined | ((options: RefreshContentOptions) => Promise<void>);
+	if (config.experimental?.contentLayer) {
+		refreshContent = async (options: RefreshContentOptions) => {
+			const contentLayer = await globalContentLayer.get();
+			await contentLayer.sync(options);
+		};
+	}
+
 	for (const integration of config.integrations) {
 		if (integration?.hooks?.['astro:server:setup']) {
 			await withTakingALongTimeMsg({
@@ -379,6 +389,7 @@ export async function runHookServerSetup({
 					server,
 					logger: getLogger(integration, logger),
 					toolbar: getToolbarServerCommunicationHelpers(server),
+					refreshContent,
 				}),
 				logger,
 			});

packages/astro/test/fixtures/content-layer/astro.config.mjs

@@ -3,7 +3,38 @@ import { defineConfig } from 'astro/config';
 import { fileURLToPath } from 'node:url';
 
 export default defineConfig({
-  integrations: [mdx()],
+  integrations: [mdx(), {
+		name: '@astrojs/my-integration',
+		hooks: {
+				'astro:server:setup': async ({ server, refreshContent }) => {
+						server.middlewares.use('/_refresh', async (req, res) => {
+								if(req.method !== 'POST') {
+									res.statusCode = 405
+									res.end('Method Not Allowed');
+									return
+								}
+								let body = '';
+								req.on('data', chunk => {
+										body += chunk.toString();
+								});
+								req.on('end', async () => {
+										try {
+												const webhookBody = JSON.parse(body);
+												await refreshContent({
+													context: { webhookBody },
+													loaders: ['increment-loader']
+												});
+												res.writeHead(200, { 'Content-Type': 'application/json' });
+												res.end(JSON.stringify({ message: 'Content refreshed successfully' }));
+										} catch (error) {
+												res.writeHead(500, { 'Content-Type': 'application/json' });
+												res.end(JSON.stringify({ error: 'Failed to refresh content' }));
+										}
+								});
+						});
+				}
+		}
+}],
 	vite: {
 		resolve: {
 			alias: {