render() — astro Function Reference

Source Code

packages/astro/src/core/render-context.ts lines 183–349

	async render(
		componentInstance: ComponentInstance | undefined,
		slots: Record<string, any> = {},
	): Promise<Response> {
		const { middleware, pipeline } = this;
		const { logger, streaming, manifest } = pipeline;
		const props =
			Object.keys(this.props).length > 0
				? this.props
				: await getProps({
						mod: componentInstance,
						routeData: this.routeData,
						routeCache: this.pipeline.routeCache,
						pathname: this.pathname,
						logger,
						serverLike: manifest.serverLike,
						base: manifest.base,
						trailingSlash: manifest.trailingSlash,
					});
		const actionApiContext = this.createActionAPIContext();
		const apiContext = this.createAPIContext(props, actionApiContext);

		this.counter++;
		if (this.counter === 4) {
			return new Response('Loop Detected', {
				// https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/508
				status: 508,
				statusText:
					'Astro detected a loop where you tried to call the rewriting logic more than four times.',
			});
		}
		const lastNext = async (ctx: APIContext, payload?: RewritePayload) => {
			if (payload) {
				const oldPathname = this.pathname;
				pipeline.logger.debug('router', 'Called rewriting to:', payload);
				// we intentionally let the error bubble up
				const {
					routeData,
					componentInstance: newComponent,
					pathname,
					newUrl,
				} = await pipeline.tryRewrite(payload, this.request);

				// This is a case where the user tries to rewrite from a SSR route to a prerendered route (SSG).
				// This case isn't valid because when building for SSR, the prerendered route disappears from the server output because it becomes an HTML file,
				// so Astro can't retrieve it from the emitted manifest.
				if (
					this.pipeline.manifest.serverLike === true &&
					this.routeData.prerender === false &&
					routeData.prerender === true
				) {
					throw new AstroError({
						...ForbiddenRewrite,
						message: ForbiddenRewrite.message(this.pathname, pathname, routeData.component),
						hint: ForbiddenRewrite.hint(routeData.component),
					});
				}

				this.routeData = routeData;
				componentInstance = newComponent;
				if (payload instanceof Request) {
					this.request = payload;
				} else {
					this.request = copyRequest(
						newUrl,
						this.request,
						// need to send the flag of the previous routeData
						routeData.prerender,
						this.pipeline.logger,
						this.routeData.route,
					);
				}
				this.isRewriting = true;
				this.url = RenderContext.#createNormalizedUrl(this.request.url);
				this.params = getParams(routeData, pathname);
				this.pathname = pathname;
				this.status = 200;
				setOriginPathname(
					this.request,
					oldPathname,
					this.pipeline.manifest.trailingSlash,