Merge pull request #620 from cudr/error_page_hooks

Error page lifecycle

runtime/src/app/app.ts

@@ -10,6 +10,7 @@ import {
 	ComponentLoader,
 	ComponentConstructor,
 	Route,
+	Query,
 	Page
 } from './types';
 import goto from './goto';
@@ -80,6 +81,20 @@ export { _history as history };
 
 export const scroll_history: Record<string, ScrollPosition> = {};
 
+export function extract_query(search: string) {
+	const query = Object.create(null);
+	if (search.length > 0) {
+		search.slice(1).split('&').forEach(searchParam => {
+			let [, key, value] = /([^=]*)(?:=(.*))?/.exec(decodeURIComponent(searchParam));
+			value = (value || '').replace(/\+/g, ' ');
+			if (typeof query[key] === 'string') query[key] = [<string>query[key]];
+			if (typeof query[key] === 'object') (query[key] as string[]).push(value);
+			else query[key] = value;
+		});
+	}
+	return query;
+}
+
 export function select_target(url: URL): Target {
 	if (url.origin !== location.origin) return null;
 	if (!url.pathname.startsWith(initial_data.baseUrl)) return null;
@@ -93,18 +108,9 @@ export function select_target(url: URL): Target {
 		const route = routes[i];
 
 		const match = route.pattern.exec(path);
-		if (match) {
-			const query: Record<string, string | string[]> = Object.create(null);
-			if (url.search.length > 0) {
-				url.search.slice(1).split('&').forEach(searchParam => {
-					let [, key, value] = /([^=]*)(?:=(.*))?/.exec(decodeURIComponent(searchParam));
-					value = (value || '').replace(/\+/g, ' ');
-					if (typeof query[key] === 'string') query[key] = [<string>query[key]];
-					if (typeof query[key] === 'object') (query[key] as string[]).push(value);
-					else query[key] = value;
-				});
-			}
 
+		if (match) {
+			const query: Query = extract_query(url.search);
 			const part = route.parts[route.parts.length - 1];
 			const params = part.params ? part.params(match) : {};
 
@@ -115,6 +121,35 @@ export function select_target(url: URL): Target {
 	}
 }
 
+export function handle_error(url: URL) {
+	const { pathname, search } = location;
+	const { session, preloaded, status, error } = initial_data;
+
+	if (!root_preloaded) {
+		root_preloaded = preloaded && preloaded[0]
+	}
+
+	const props = {
+		error,
+		status,
+		session,
+		level0: {
+			props: root_preloaded
+		},
+		level1: {
+			props: {
+				status,
+				error
+			},
+			component: ErrorComponent
+		},
+		segments: preloaded
+
+	}
+	const query = extract_query(search);
+	render(null, [], props, { path: pathname, query, params: {} });
+}
+
 export function scroll_state() {
 	return {
 		x: pageXOffset,

runtime/src/app/start/index.ts

@@ -6,6 +6,7 @@ import {
 	scroll_history,
 	scroll_state,
 	select_target,
+	handle_error,
 	set_target,
 	uid,
 	set_uid,
@@ -34,10 +35,12 @@ export default function start(opts: {
 
 		history.replaceState({ id: uid }, '', href);
 
-		if (!initial_data.error) {
-			const target = select_target(new URL(location.href));
-			if (target) return navigate(target, uid, false, hash);
-		}
+		const url = new URL(location.href);
+
+		if (initial_data.error) return handle_error(url);
+
+		const target = select_target(url);
+		if (target) return navigate(target, uid, false, hash);
 	});
 }
 
@@ -127,4 +130,4 @@ function handle_popstate(event: PopStateEvent) {
 		set_cid(uid);
 		history.replaceState({ id: cid }, '', location.href);
 	}
-}
+}

runtime/src/server/middleware/get_page_handler.ts

@@ -243,11 +243,12 @@ export function get_page_handler(
 				preloaded: `[${preloaded.map(data => try_serialize(data)).join(',')}]`,
 				session: session && try_serialize(session, err => {
 					throw new Error(`Failed to serialize session data: ${err.message}`);
-				})
+				}),
+				error: error && try_serialize(props.error)
 			};
 
 			let script = `__SAPPER__={${[
-				error && `error:1`,
+				error && `error:${serialized.error},status:${status}`,
 				`baseUrl:"${req.baseUrl}"`,
 				serialized.preloaded && `preloaded:${serialized.preloaded}`,
 				serialized.session && `session:${serialized.session}`