Use status 308 for non-GET redirects (#7186)

packages/astro/src/core/app/index.ts

@@ -28,6 +28,7 @@ import {
 	createStylesheetElementSet,
 } from '../render/ssr-element.js';
 import { matchRoute } from '../routing/match.js';
+import { RedirectComponentInstance } from '../redirects/index.js';
 export { deserializeManifest } from './common.js';
 
 const clientLocalsSymbol = Symbol.for('astro.locals');
@@ -139,20 +140,20 @@ export class App {
 			defaultStatus = 404;
 		}
 
-		let mod = await this.#manifest.pageMap.get(routeData.component)!();
+		let mod = await this.#getModuleForRoute(routeData);
 
-		if (routeData.type === 'page') {
+		if (routeData.type === 'page' || routeData.type === 'redirect') {
 			let response = await this.#renderPage(request, routeData, mod, defaultStatus);
 
 			// If there was a known error code, try sending the according page (e.g. 404.astro / 500.astro).
 			if (response.status === 500 || response.status === 404) {
-				const errorPageData = matchRoute('/' + response.status, this.#manifestData);
-				if (errorPageData && errorPageData.route !== routeData.route) {
-					mod = await this.#manifest.pageMap.get(errorPageData.component)!();
+				const errorRouteData = matchRoute('/' + response.status, this.#manifestData);
+				if (errorRouteData && errorRouteData.route !== routeData.route) {
+					mod = await this.#getModuleForRoute(errorRouteData);
 					try {
 						let errorResponse = await this.#renderPage(
 							request,
-							errorPageData,
+							errorRouteData,
 							mod,
 							response.status
 						);
@@ -172,6 +173,14 @@ export class App {
 		return getSetCookiesFromResponse(response);
 	}
 
+	async #getModuleForRoute(route: RouteData): Promise<ComponentInstance> {
+		if(route.type === 'redirect') {
+			return RedirectComponentInstance;
+		} else {
+			return  await this.#manifest.pageMap.get(route.component)!();
+		}
+	}
+
 	async #renderPage(
 		request: Request,
 		routeData: RouteData,

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

@@ -35,7 +35,7 @@ import { debug, info } from '../logger/core.js';
 import { callMiddleware } from '../middleware/callMiddleware.js';
 import { createEnvironment, createRenderContext, renderPage } from '../render/index.js';
 import { callGetStaticPaths } from '../render/route-cache.js';
-import { getRedirectLocationOrThrow, routeIsRedirect } from '../redirects/index.js';
+import { getRedirectLocationOrThrow, routeIsRedirect, RedirectComponentInstance } from '../redirects/index.js';
 import {	
 	createAssetLink,
 	createModuleScriptsSet,
@@ -177,7 +177,7 @@ async function generatePage(
 		if(pageData.route.redirectRoute) {
 			pageModulePromise = ssrEntry.pageMap?.get(pageData.route.redirectRoute!.component);
 		} else {
-			pageModulePromise = () => Promise.resolve<any>({ default: () => {} });
+			pageModulePromise = () => Promise.resolve(RedirectComponentInstance);
 		}
 	}
 	if (!pageModulePromise) {

packages/astro/src/core/redirects/component.ts

@@ -0,0 +1,10 @@
+import type { ComponentInstance } from '../../@types/astro';
+
+// A stub of a component instance for a given route
+export const RedirectComponentInstance: ComponentInstance = {
+	default() {
+		return new Response(null, {
+			status: 301
+		});
+	}
+};

packages/astro/src/core/redirects/helpers.ts

@@ -18,10 +18,12 @@ export function redirectRouteGenerate(redirectRoute: RouteData, data: Params): s
 	return route.destination;
 }
 
-export function redirectRouteStatus(redirectRoute: RouteData): ValidRedirectStatus {
+export function redirectRouteStatus(redirectRoute: RouteData, method = 'GET'): ValidRedirectStatus {
 	const routeData = redirectRoute.redirectRoute;
 	if(typeof routeData?.redirect === 'object') {
 		return routeData.redirect.status;
+	} else if(method !== 'GET') {
+		return 308;
 	}
 	return 301;
 }

packages/astro/src/core/redirects/index.ts

@@ -1,2 +1,3 @@
 export { getRedirectLocationOrThrow } from './validate.js';
 export { routeIsRedirect, redirectRouteGenerate, redirectRouteStatus } from './helpers.js';
+export { RedirectComponentInstance } from './component.js';

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

@@ -114,7 +114,7 @@ export type RenderPage = {
 export async function renderPage({ mod, renderContext, env, apiContext }: RenderPage) {
 	if(routeIsRedirect(renderContext.route)) {
 		return new Response(null, {
-			status: redirectRouteStatus(renderContext.route),
+			status: redirectRouteStatus(renderContext.route, renderContext.request.method),
 			headers: {
 				location: redirectRouteGenerate(renderContext.route, renderContext.params)
 			}

packages/astro/test/redirects.test.js

@@ -12,6 +12,9 @@ describe('Astro.redirect', () => {
 				root: './fixtures/ssr-redirect/',
 				output: 'server',
 				adapter: testAdapter(),
+				redirects: {
+					'/api/redirect': '/'
+				}
 			});
 			await fixture.build();
 		});
@@ -37,6 +40,25 @@ describe('Astro.redirect', () => {
 				);
 			}
 		});
+
+		describe('Redirects config', () => {
+			it('Returns the redirect', async () => {
+				const app = await fixture.loadTestAdapterApp();
+				const request = new Request('http://example.com/api/redirect');
+				const response = await app.render(request);
+				expect(response.status).to.equal(301);
+				expect(response.headers.get('Location')).to.equal('/');
+			});
+
+			it('Uses 308 for non-GET methods', async () => {
+				const app = await fixture.loadTestAdapterApp();
+				const request = new Request('http://example.com/api/redirect', {
+					method: 'POST'
+				});
+				const response = await app.render(request);
+				expect(response.status).to.equal(308);
+			});
+		});
 	});
 
 	describe('output: "static"', () => {