-> v0.13.0

[WIP] expose dev, build, export APIs

CHANGELOG.md

@@ -1,5 +1,14 @@
 # sapper changelog
 
+## 0.13.0
+
+* Expose `dev`, `build`, `export` and `find_page` APIs ([#272](https://github.com/sveltejs/sapper/issues/272))
+
+## 0.12.0
+
+* Each app has a single `<App>` component. See the [migration guide](https://sapper.svelte.technology/guide#0-11-to-0-12) for more information ([#157](https://github.com/sveltejs/sapper/issues/157))
+* Process exits with error code 1 if build/export fails ([#208](https://github.com/sveltejs/sapper/issues/208))
+
 ## 0.11.1
 
 * Limit routes with leading dots to `.well-known` URIs ([#252](https://github.com/sveltejs/sapper/issues/252))

api.js

@@ -0,0 +1 @@
+module.exports = require('./dist/api.ts.js');

package.json

@@ -1,6 +1,6 @@
 {
   "name": "sapper",
-  "version": "0.11.1",
+  "version": "0.13.0",
   "description": "Military-grade apps, engineered by Svelte",
   "main": "dist/middleware.ts.js",
   "bin": {
@@ -18,26 +18,26 @@
     "test": "test"
   },
   "dependencies": {
+    "ansi-colors": "^2.0.1",
     "cheerio": "^1.0.0-rc.2",
     "chokidar": "^2.0.3",
-    "clorox": "^1.0.3",
     "cookie": "^0.3.1",
     "devalue": "^1.0.1",
     "glob": "^7.1.2",
-    "html-minifier": "^3.5.11",
+    "html-minifier": "^3.5.16",
     "mkdirp": "^0.5.1",
     "node-fetch": "^2.1.1",
     "port-authority": "^1.0.2",
-    "pretty-bytes": "^4.0.2",
+    "pretty-bytes": "^5.0.0",
     "pretty-ms": "^3.1.0",
     "require-relative": "^0.8.7",
     "rimraf": "^2.6.2",
-    "sade": "^1.4.0",
+    "sade": "^1.4.1",
     "sander": "^0.6.0",
-    "source-map-support": "^0.5.5",
-    "tslib": "^1.9.0",
+    "source-map-support": "^0.5.6",
+    "tslib": "^1.9.1",
     "url-parse": "^1.2.0",
-    "webpack-format-messages": "^1.0.2"
+    "webpack-format-messages": "^2.0.1"
   },
   "devDependencies": {
     "@types/glob": "^5.0.34",
@@ -45,23 +45,23 @@
     "@types/rimraf": "^2.0.2",
     "compression": "^1.7.1",
     "eslint": "^4.13.1",
-    "eslint-plugin-import": "^2.8.0",
+    "eslint-plugin-import": "^2.12.0",
     "express": "^4.16.3",
-    "mocha": "^5.0.4",
+    "mocha": "^5.2.0",
     "nightmare": "^3.0.0",
-    "npm-run-all": "^4.1.2",
-    "polka": "^0.3.4",
-    "rollup": "^0.58.2",
+    "npm-run-all": "^4.1.3",
+    "polka": "^0.4.0",
+    "rollup": "^0.59.2",
     "rollup-plugin-commonjs": "^9.1.3",
-    "rollup-plugin-json": "^2.3.0",
+    "rollup-plugin-json": "^3.0.0",
     "rollup-plugin-string": "^2.0.2",
     "rollup-plugin-typescript": "^0.8.1",
     "serve-static": "^1.13.2",
-    "svelte": "^2.4.4",
+    "svelte": "^2.6.3",
     "svelte-loader": "^2.9.0",
     "typescript": "^2.8.3",
     "walk-sync": "^0.3.2",
-    "webpack": "^4.1.0"
+    "webpack": "^4.8.3"
   },
   "scripts": {
     "cy:open": "cypress open",

rollup.config.js

@@ -25,7 +25,13 @@ export default [
 	},
 
 	{
-		input: [`src/cli.ts`, `src/core.ts`, `src/middleware.ts`, `src/webpack.ts`],
+		input: [
+			`src/api.ts`,
+			`src/cli.ts`,
+			`src/core.ts`,
+			`src/middleware.ts`,
+			`src/webpack.ts`
+		],
 		output: {
 			dir: 'dist',
 			format: 'cjs',

src/api.ts

@@ -0,0 +1,6 @@
+import { dev } from './api/dev';
+import { build } from './api/build';
+import { exporter } from './api/export';
+import { find_page } from './api/find_page';
+
+export { dev, build, exporter, find_page };

src/api/build.ts

@@ -0,0 +1,111 @@
+import * as fs from 'fs';
+import * as path from 'path';
+import mkdirp from 'mkdirp';
+import rimraf from 'rimraf';
+import { EventEmitter } from 'events';
+import { minify_html } from './utils/minify_html';
+import { create_compilers, create_main_manifests, create_routes, create_serviceworker_manifest } from '../core'
+import { locations } from '../config';
+import * as events from './interfaces';
+
+export function build(opts: {}) {
+	const emitter = new EventEmitter();
+
+	execute(emitter, opts).then(
+		() => {
+			emitter.emit('done', <events.DoneEvent>{}); // TODO do we need to pass back any info?
+		},
+		error => {
+			emitter.emit('error', <events.ErrorEvent>{
+				error
+			});
+		}
+	);
+
+	return emitter;
+}
+
+async function execute(emitter: EventEmitter, {
+	dest = 'build',
+	app = 'app',
+	webpack = 'webpack',
+	routes = 'routes'
+} = {}) {
+	mkdirp.sync(dest);
+	rimraf.sync(path.join(dest, '**/*'));
+
+	// minify app/template.html
+	// TODO compile this to a function? could be quicker than str.replace(...).replace(...).replace(...)
+	const template = fs.readFileSync(`${app}/template.html`, 'utf-8');
+
+	// remove this in a future version
+	if (template.indexOf('%sapper.base%') === -1) {
+		const error = new Error(`As of Sapper v0.10, your template.html file must include %sapper.base% in the <head>`);
+		error.code = `missing-sapper-base`;
+		throw error;
+	}
+
+	fs.writeFileSync(`${dest}/template.html`, minify_html(template));
+
+	const route_objects = create_routes();
+
+	// create app/manifest/client.js and app/manifest/server.js
+	create_main_manifests({ routes: route_objects });
+
+	const { client, server, serviceworker } = create_compilers({ webpack });
+
+	const client_stats = await compile(client);
+	emitter.emit('build', <events.BuildEvent>{
+		type: 'client',
+		// TODO duration/warnings
+		webpack_stats: client_stats
+	});
+
+	const client_info = client_stats.toJson();
+	fs.writeFileSync(path.join(dest, 'client_info.json'), JSON.stringify(client_info));
+	fs.writeFileSync(path.join(dest, 'client_assets.json'), JSON.stringify(client_info.assetsByChunkName));
+
+	const server_stats = await compile(server);
+	emitter.emit('build', <events.BuildEvent>{
+		type: 'server',
+		// TODO duration/warnings
+		webpack_stats: server_stats
+	});
+
+	let serviceworker_stats;
+
+	if (serviceworker) {
+		create_serviceworker_manifest({
+			routes: route_objects,
+			client_files: client_stats.toJson().assets.map((chunk: { name: string }) => `client/${chunk.name}`)
+		});
+
+		serviceworker_stats = await compile(serviceworker);
+
+		emitter.emit('build', <events.BuildEvent>{
+			type: 'serviceworker',
+			// TODO duration/warnings
+			webpack_stats: serviceworker_stats
+		});
+	}
+}
+
+function compile(compiler: any) {
+	return new Promise((fulfil, reject) => {
+		compiler.run((err: Error, stats: any) => {
+			if (err) {
+				reject(err);
+				process.exit(1);
+			}
+
+			if (stats.hasErrors()) {
+				console.error(stats.toString({ colors: true }));
+				reject(new Error(`Encountered errors while building app`));
+			}
+
+			else {
+				fulfil(stats);
+			}
+		});
+	});
+}

src/api/dev.ts

@@ -0,0 +1,422 @@
+import * as path from 'path';
+import * as fs from 'fs';
+import * as http from 'http';
+import * as child_process from 'child_process';
+import * as ports from 'port-authority';
+import mkdirp from 'mkdirp';
+import rimraf from 'rimraf';
+import format_messages from 'webpack-format-messages';
+import prettyMs from 'pretty-ms';
+import { locations } from '../config';
+import { EventEmitter } from 'events';
+import { create_routes, create_main_manifests, create_compilers, create_serviceworker_manifest } from '../core';
+import * as events from './interfaces';
+
+export function dev(opts) {
+	return new Watcher(opts);
+}
+
+class Watcher extends EventEmitter {
+	dirs: {
+		app: string;
+		dest: string;
+		routes: string;
+		webpack: string;
+	}
+	port: number;
+	closed: boolean;
+
+	dev_server: DevServer;
+	proc: child_process.ChildProcess;
+	filewatchers: Array<{ close: () => void }>;
+	deferreds: {
+		client: Deferred;
+		server: Deferred;
+	};
+
+	restarting: boolean;
+	current_build: {
+		changed: Set<string>;
+		rebuilding: Set<string>;
+		unique_warnings: Set<string>;
+		unique_errors: Set<string>;
+	}
+
+	constructor({
+		app = locations.app(),
+		dest = locations.dest(),
+		routes = locations.routes(),
+		webpack = 'webpack',
+		port = +process.env.PORT
+	}: {
+		app: string,
+		dest: string,
+		routes: string,
+		webpack: string,
+		port: number
+	}) {
+		super();
+
+		this.dirs = { app, dest, routes, webpack };
+		this.port = port;
+		this.closed = false;
+
+		this.filewatchers = [];
+
+		this.current_build = {
+			changed: new Set(),
+			rebuilding: new Set(),
+			unique_errors: new Set(),
+			unique_warnings: new Set()
+		};
+
+		// remove this in a future version
+		const template = fs.readFileSync(path.join(app, 'template.html'), 'utf-8');
+		if (template.indexOf('%sapper.base%') === -1) {
+			const error = new Error(`As of Sapper v0.10, your template.html file must include %sapper.base% in the <head>`);
+			error.code = `missing-sapper-base`;
+			throw error;
+		}
+
+		process.env.NODE_ENV = 'development';
+
+		process.on('exit', () => {
+			this.close();
+		});
+
+		this.init();
+	}
+
+	async init() {
+		if (this.port) {
+			if (!await ports.check(this.port)) {
+				this.emit('fatal', <events.FatalEvent>{
+					error: new Error(`Port ${this.port} is unavailable`)
+				});
+				return;
+			}
+		} else {
+			this.port = await ports.find(3000);
+		}
+
+		const { dest } = this.dirs;
+		rimraf.sync(dest);
+		mkdirp.sync(dest);
+
+		const dev_port = await ports.find(10000);
+
+		const routes = create_routes();
+		create_main_manifests({ routes, dev_port });
+
+		this.dev_server = new DevServer(dev_port);
+
+		this.filewatchers.push(
+			watch_files(locations.routes(), ['add', 'unlink'], () => {
+				const routes = create_routes();
+				create_main_manifests({ routes, dev_port });
+			}),
+
+			watch_files(`${locations.app()}/template.html`, ['change'], () => {
+				this.dev_server.send({
+					action: 'reload'
+				});
+			})
+		);
+
+		this.deferreds = {
+			server: new Deferred(),
+			client: new Deferred()
+		};
+
+		// TODO watch the configs themselves?
+		const compilers = create_compilers({ webpack: this.dirs.webpack });
+
+		this.watch(compilers.server, {
+			name: 'server',
+
+			invalid: filename => {
+				this.restart(filename, 'server');
+				this.deferreds.server = new Deferred();
+			},
+
+			result: info => {
+				fs.writeFileSync(path.join(dest, 'server_info.json'), JSON.stringify(info, null, '  '));
+
+				this.deferreds.client.promise.then(() => {
+					this.dev_server.send({
+						status: 'completed'
+					});
+
+					const restart = () => {
+						ports.wait(this.port).then((() => {
+							this.emit('ready', <events.ReadyEvent>{
+								port: this.port,
+								process: this.proc
+							});
+
+							this.deferreds.server.fulfil();
+						}));
+					};
+
+					if (this.proc) {
+						this.proc.kill();
+						this.proc.on('exit', restart);
+					} else {
+						restart();
+					}
+
+					this.proc = child_process.fork(`${dest}/server.js`, [], {
+						cwd: process.cwd(),
+						env: Object.assign({
+							PORT: this.port
+						}, process.env),
+						stdio: ['ipc']
+					});
+				});
+			}
+		});
+
+		let first = true;
+
+		this.watch(compilers.client, {
+			name: 'client',
+
+			invalid: filename => {
+				this.restart(filename, 'client');
+				this.deferreds.client = new Deferred();
+
+				// TODO we should delete old assets. due to a webpack bug
+				// i don't even begin to comprehend, this is apparently
+				// quite difficult
+			},
+
+			result: info => {
+				fs.writeFileSync(path.join(dest, 'client_info.json'), JSON.stringify(info));
+				fs.writeFileSync(path.join(dest, 'client_assets.json'), JSON.stringify(info.assetsByChunkName, null, '  '));
+				this.deferreds.client.fulfil();
+
+				const client_files = info.assets.map((chunk: { name: string }) => `client/${chunk.name}`);
+
+				create_serviceworker_manifest({
+					routes: create_routes(),
+					client_files
+				});
+
+				// we need to wait a beat before watching the service
+				// worker, because of some webpack nonsense
+				setTimeout(watch_serviceworker, 100);
+			}
+		});
+
+		let watch_serviceworker = compilers.serviceworker
+			? () => {
+				watch_serviceworker = noop;
+
+				this.watch(compilers.serviceworker, {
+					name: 'service worker',
+
+					result: info => {
+						fs.writeFileSync(path.join(dest, 'serviceworker_info.json'), JSON.stringify(info, null, '  '));
+					}
+				});
+			}
+			: noop;
+	}
+
+	close() {
+		if (this.closed) return;
+		this.closed = true;
+
+		this.dev_server.close();
+
+		if (this.proc) this.proc.kill();
+		this.filewatchers.forEach(watcher => {
+			watcher.close();
+		});
+	}
+
+	restart(filename: string, type: string) {
+		if (this.restarting) {
+			this.current_build.changed.add(filename);
+			this.current_build.rebuilding.add(type);
+		} else {
+			this.restarting = true;
+
+			this.current_build = {
+				changed: new Set(),
+				rebuilding: new Set(),
+				unique_warnings: new Set(),
+				unique_errors: new Set()
+			};
+
+			process.nextTick(() => {
+				this.emit('invalid', <events.InvalidEvent>{
+					changed: Array.from(this.current_build.changed),
+					invalid: {
+						server: this.current_build.rebuilding.has('server'),
+						client: this.current_build.rebuilding.has('client'),
+						serviceworker: this.current_build.rebuilding.has('serviceworker'),
+					}
+				});
+
+				this.restarting = false;
+			});
+		}
+	}
+
+	watch(compiler: any, { name, invalid = noop, result }: {
+		name: string,
+		invalid?: (filename: string) => void;
+		result: (stats: any) => void;
+	}) {
+		compiler.hooks.invalid.tap('sapper', (filename: string) => {
+			invalid(filename);
+		});
+
+		compiler.watch({}, (err: Error, stats: any) => {
+			if (err) {
+				this.emit('error', <events.ErrorEvent>{
+					type: name,
+					error: err
+				});
+			} else {
+				const messages = format_messages(stats);
+				const info = stats.toJson();
+
+				this.emit('build', {
+					type: name,
+
+					duration: info.time,
+
+					errors: messages.errors.map((message: string) => {
+						const duplicate = this.current_build.unique_errors.has(message);
+						this.current_build.unique_errors.add(message);
+
+						return mungeWebpackError(message, duplicate);
+					}),
+
+					warnings: messages.warnings.map((message: string) => {
+						const duplicate = this.current_build.unique_warnings.has(message);
+						this.current_build.unique_warnings.add(message);
+
+						return mungeWebpackError(message, duplicate);
+					}),
+				});
+
+				result(info);
+			}
+		});
+	}
+}
+
+const locPattern = /\((\d+):(\d+)\)$/;
+
+function mungeWebpackError(message: string, duplicate: boolean) {
+	// TODO this is all a bit rube goldberg...
+	const lines = message.split('\n');
+
+	const file = lines.shift()
+		.replace('', '') // careful — there is a special character at the beginning of this string
+		.replace('', '')
+		.replace('./', '');
+
+	let line = null;
+	let column = null;
+
+	const match = locPattern.exec(lines[0]);
+	if (match) {
+		lines[0] = lines[0].replace(locPattern, '');
+		line = +match[1];
+		column = +match[2];
+	}
+
+	return {
+		file,
+		line,
+		column,
+		message: lines.join('\n'),
+		originalMessage: message,
+		duplicate
+	};
+}
+
+class Deferred {
+	promise: Promise<any>;
+	fulfil: (value?: any) => void;
+	reject: (error: Error) => void;
+
+	constructor() {
+		this.promise = new Promise((fulfil, reject) => {
+			this.fulfil = fulfil;
+			this.reject = reject;
+		});
+	}
+}
+
+class DevServer {
+	clients: Set<http.ServerResponse>;
+	_: http.Server;
+
+	constructor(port: number, interval = 10000) {
+		this.clients = new Set();
+
+		this._ = http.createServer((req, res) => {
+			if (req.url !== '/__sapper__') return;
+
+			req.socket.setKeepAlive(true);
+			res.writeHead(200, {
+				'Access-Control-Allow-Origin': '*',
+				'Access-Control-Allow-Headers': 'Cache-Control',
+				'Content-Type': 'text/event-stream;charset=utf-8',
+				'Cache-Control': 'no-cache, no-transform',
+				'Connection': 'keep-alive',
+				// While behind nginx, event stream should not be buffered:
+				// http://nginx.org/docs/http/ngx_http_proxy_module.html#proxy_buffering
+				'X-Accel-Buffering': 'no'
+			});
+
+			res.write('\n');
+
+			this.clients.add(res);
+			req.on('close', () => {
+				this.clients.delete(res);
+			});
+		});
+
+		this._.listen(port);
+
+		setInterval(() => {
+			this.send(null);
+		});
+	}
+
+	close() {
+		this._.close();
+	}
+
+	send(data: any) {
+		this.clients.forEach(client => {
+			client.write(`data: ${JSON.stringify(data)}\n\n`);
+		});
+	}
+}
+
+function noop() {}
+
+function watch_files(pattern: string, events: string[], callback: () => void) {
+	const chokidar = require('chokidar');
+
+	const watcher = chokidar.watch(pattern, {
+		persistent: true,
+		ignoreInitial: true,
+		disableGlobbing: true
+	});
+
+	events.forEach(event => {
+		watcher.on(event, callback);
+	});
+
+	return {
+		close: () => watcher.close()
+	};
+}

src/api/export.ts

@@ -0,0 +1,131 @@
+import * as child_process from 'child_process';
+import * as path from 'path';
+import * as sander from 'sander';
+import cheerio from 'cheerio';
+import URL from 'url-parse';
+import fetch from 'node-fetch';
+import * as ports from 'port-authority';
+import { EventEmitter } from 'events';
+import { minify_html } from './utils/minify_html';
+import { locations } from '../config';
+import * as events from './interfaces';
+
+export function exporter(opts: {}) {
+	const emitter = new EventEmitter();
+
+	execute(emitter, opts).then(
+		() => {
+			emitter.emit('done', <events.DoneEvent>{}); // TODO do we need to pass back any info?
+		},
+		error => {
+			emitter.emit('error', <events.ErrorEvent>{
+				error
+			});
+		}
+	);
+
+	return emitter;
+}
+
+async function execute(emitter: EventEmitter, {
+	build = 'build',
+	dest = 'export',
+	basepath = ''
+} = {}) {
+	const export_dir = path.join(dest, basepath);
+
+	// Prep output directory
+	sander.rimrafSync(export_dir);
+
+	sander.copydirSync('assets').to(export_dir);
+	sander.copydirSync(build, 'client').to(export_dir, 'client');
+
+	if (sander.existsSync(build, 'service-worker.js')) {
+		sander.copyFileSync(build, 'service-worker.js').to(export_dir, 'service-worker.js');
+	}
+
+	if (sander.existsSync(build, 'service-worker.js.map')) {
+		sander.copyFileSync(build, 'service-worker.js.map').to(export_dir, 'service-worker.js.map');
+	}
+
+	const port = await ports.find(3000);
+
+	const origin = `http://localhost:${port}`;
+
+	const proc = child_process.fork(path.resolve(`${build}/server.js`), [], {
+		cwd: process.cwd(),
+		env: Object.assign({
+			PORT: port,
+			NODE_ENV: 'production',
+			SAPPER_DEST: build,
+			SAPPER_EXPORT: 'true'
+		}, process.env)
+	});
+
+	const seen = new Set();
+	const saved = new Set();
+
+	proc.on('message', message => {
+		if (!message.__sapper__) return;
+
+		let file = new URL(message.url, origin).pathname.slice(1);
+		let { body } = message;
+
+		if (saved.has(file)) return;
+		saved.add(file);
+
+		const is_html = message.type === 'text/html';
+
+		if (is_html) {
+			file = file === '' ? 'index.html' : `${file}/index.html`;
+			body = minify_html(body);
+		}
+
+		emitter.emit('file', <events.FileEvent>{
+			file,
+			size: body.length
+		});
+
+		sander.writeFileSync(export_dir, file, body);
+	});
+
+	async function handle(url: URL) {
+		const r = await fetch(url.href);
+		const range = ~~(r.status / 100);
+
+		if (range >= 4) {
+			emitter.emit('failure', <events.FailureEvent>{
+				status: r.status,
+				pathname: url.pathname
+			});
+			return;
+		}
+
+		if (range === 2) {
+			if (r.headers.get('Content-Type') === 'text/html') {
+				const body = await r.text();
+				const $ = cheerio.load(body);
+				const urls: URL[] = [];
+
+				const base = new URL($('base').attr('href') || '/', url.href);
+
+				$('a[href]').each((i: number, $a) => {
+					const url = new URL($a.attribs.href, base.href);
+
+					if (url.origin === origin && !seen.has(url.pathname)) {
+						seen.add(url.pathname);
+						urls.push(url);
+					}
+				});
+
+				for (const url of urls) {
+					await handle(url);
+				}
+			}
+		}
+	}
+
+	return ports.wait(port)
+		.then(() => handle(new URL(`/${basepath}`, origin))) // TODO all static routes
+		.then(() => proc.kill());
+}

src/api/find_page.ts

@@ -0,0 +1,16 @@
+import * as glob from 'glob';
+import { locations } from '../config';
+import { create_routes } from '../core';
+
+export function find_page(pathname: string, files: string[] = glob.sync('**/*.*', { cwd: locations.routes(), dot: true, nodir: true })) {
+	const routes = create_routes({ files });
+
+	for (let i = 0; i < routes.length; i += 1) {
+		const route = routes[i];
+
+		if (route.pattern.test(pathname)) {
+			const page = route.handlers.find(handler => handler.type === 'page');
+			if (page) return page.file;
+		}
+	}
+}

src/api/interfaces.ts

@@ -0,0 +1,43 @@
+import * as child_process from 'child_process';
+
+export type ReadyEvent = {
+	port: number;
+	process: child_process.ChildProcess;
+};
+
+export type ErrorEvent = {
+	type: string;
+	error: Error;
+};
+
+export type FatalEvent = {
+	error: Error;
+};
+
+export type InvalidEvent = {
+	changed: string[];
+	invalid: {
+		client: boolean;
+		server: boolean;
+		serviceworker: boolean;
+	}
+};
+
+export type BuildEvent = {
+	type: string;
+	errors: Array<{ message: string, duplicate: boolean }>;
+	warnings: Array<{ message: string, duplicate: boolean }>;
+	duration: number;
+	webpack_stats: any;
+}
+
+export type FileEvent = {
+	file: string;
+	size: number;
+}
+
+export type FailureEvent = {
+
+}
+
+export type DoneEvent = {}

src/cli.ts

@@ -2,7 +2,7 @@ import * as fs from 'fs';
 import * as path from 'path';
 import * as child_process from 'child_process';
 import sade from 'sade';
-import * as clorox from 'clorox';
+import * as colors from 'ansi-colors';
 import prettyMs from 'pretty-ms';
 // import upgrade from './cli/upgrade';
 import * as ports from 'port-authority';
@@ -47,9 +47,10 @@ prog.command('build [dest]')
 				require('./server.js');
 			`.replace(/^\t+/gm, '').trim());
 
-			console.error(`\n> Finished in ${elapsed(start)}. Type ${clorox.bold.cyan(`node ${dest}`)} to run the app.`);
+			console.error(`\n> Finished in ${elapsed(start)}. Type ${colors.bold.cyan(`node ${dest}`)} to run the app.`);
 		} catch (err) {
 			console.error(err ? err.details || err.stack || err.message || err : 'Unknown error');
+			process.exit(1);
 		}
 	});
 
@@ -80,9 +81,10 @@ prog.command('export [dest]')
 
 			const { exporter } = await import('./cli/export');
 			await exporter(dest, opts);
-			console.error(`\n> Finished in ${elapsed(start)}. Type ${clorox.bold.cyan(`npx serve ${dest}`)} to run the app.`);
+			console.error(`\n> Finished in ${elapsed(start)}. Type ${colors.bold.cyan(`npx serve ${dest}`)} to run the app.`);
 		} catch (err) {
 			console.error(err ? err.details || err.stack || err.message || err : 'Unknown error');
+			process.exit(1);
 		}
 	});
 
@@ -92,4 +94,4 @@ prog.parse(process.argv);
 
 function elapsed(start: number) {
 	return prettyMs(Date.now() - start);
-}
+}

src/cli/build.ts

@@ -1,78 +1,32 @@
-import * as fs from 'fs';
-import * as path from 'path';
-import * as clorox from 'clorox';
-import mkdirp from 'mkdirp';
-import rimraf from 'rimraf';
-import { minify_html } from './utils/minify_html';
-import { create_compilers, create_main_manifests, create_routes, create_serviceworker_manifest } from '../core'
+import { build as _build } from '../api/build';
+import * as colors from 'ansi-colors';
 import { locations } from '../config';
 
-export async function build() {
-	const output = locations.dest();
-
-	mkdirp.sync(output);
-	rimraf.sync(path.join(output, '**/*'));
-
-	// minify app/template.html
-	// TODO compile this to a function? could be quicker than str.replace(...).replace(...).replace(...)
-	const template = fs.readFileSync(`${locations.app()}/template.html`, 'utf-8');
-
-	// remove this in a future version
-	if (template.indexOf('%sapper.base%') === -1) {
-		console.log(`${clorox.bold.red(`> As of Sapper v0.10, your template.html file must include %sapper.base% in the <head>`)}`);
-		process.exit(1);
-	}
-
-	fs.writeFileSync(`${output}/template.html`, minify_html(template));
-
-	const routes = create_routes();
-
-	// create app/manifest/client.js and app/manifest/server.js
-	create_main_manifests({ routes });
-
-	const { client, server, serviceworker } = create_compilers();
-
-	const client_stats = await compile(client);
-	console.log(`${clorox.inverse(`\nbuilt client`)}`);
-	console.log(client_stats.toString({ colors: true }));
-	fs.writeFileSync(path.join(output, 'client_info.json'), JSON.stringify({
-		assets: client_stats.toJson().assetsByChunkName
-	}));
-
-	const server_stats = await compile(server);
-	console.log(`${clorox.inverse(`\nbuilt server`)}`);
-	console.log(server_stats.toString({ colors: true }));
-
-	let serviceworker_stats;
-
-	if (serviceworker) {
-		create_serviceworker_manifest({
-			routes,
-			client_files: client_stats.toJson().assets.map((chunk: { name: string }) => `client/${chunk.name}`)
-		});
-
-		serviceworker_stats = await compile(serviceworker);
-		console.log(`${clorox.inverse(`\nbuilt service worker`)}`);
-		console.log(serviceworker_stats.toString({ colors: true }));
-	}
-}
-
-function compile(compiler: any) {
+export function build() {
 	return new Promise((fulfil, reject) => {
-		compiler.run((err: Error, stats: any) => {
-			if (err) {
-				reject(err);
-				process.exit(1);
-			}
+		try {
+			const emitter = _build({
+				dest: locations.dest(),
+				app: locations.app(),
+				routes: locations.routes(),
+				webpack: 'webpack'
+			});
 
-			if (stats.hasErrors()) {
-				console.error(stats.toString({ colors: true }));
-				reject(new Error(`Encountered errors while building app`));
-			}
+			emitter.on('build', event => {
+				console.log(colors.inverse(`\nbuilt ${event.type}`));
+				console.log(event.webpack_stats.toString({ colors: true }));
+			});
 
-			else {
-				fulfil(stats);
-			}
-		});
+			emitter.on('error', event => {
+				reject(event.error);
+			});
+
+			emitter.on('done', event => {
+				fulfil();
+			});
+		} catch (err) {
+			console.log(`${colors.bold.red(`> ${err.message}`)}`);
+			process.exit(1);
+		}
 	});
-}
+}

src/cli/dev.ts

@@ -1,323 +1,77 @@
-import * as fs from 'fs';
 import * as path from 'path';
-import * as net from 'net';
-import * as clorox from 'clorox';
+import * as colors from 'ansi-colors';
 import * as child_process from 'child_process';
-import * as http from 'http';
-import mkdirp from 'mkdirp';
-import rimraf from 'rimraf';
-import format_messages from 'webpack-format-messages';
 import prettyMs from 'pretty-ms';
-import * as ports from 'port-authority';
-import { locations } from '../config';
-import { create_compilers, create_main_manifests, create_routes, create_serviceworker_manifest } from '../core';
+import { dev as _dev } from '../api/dev';
+import * as events from '../api/interfaces';
 
-type Deferred = {
-	promise?: Promise<any>;
-	fulfil?: (value?: any) => void;
-	reject?: (err: Error) => void;
-}
+export function dev(opts: { port: number, open: boolean }) {
+	try {
+		const watcher = _dev(opts);
 
-function deferred() {
-	const d: Deferred = {};
+		let first = true;
 
-	d.promise = new Promise((fulfil, reject) => {
-		d.fulfil = fulfil;
-		d.reject = reject;
-	});
+		watcher.on('ready', (event: events.ReadyEvent) => {
+			if (first) {
+				console.log(`${colors.bold.cyan(`> Listening on http://localhost:${event.port}`)}`);
+				if (opts.open) child_process.exec(`open http://localhost:${event.port}`);
+				first = false;
+			}
 
-	return d;
-}
+			// TODO clear screen?
 
-function create_hot_update_server(port: number, interval = 10000) {
-	const clients = new Set();
+			event.process.stdout.on('data', data => {
+				process.stdout.write(data);
+			});
 
-	const server = http.createServer((req, res) => {
-		if (req.url !== '/__sapper__') return;
-
-		req.socket.setKeepAlive(true);
-		res.writeHead(200, {
-			'Access-Control-Allow-Origin': '*',
-			'Access-Control-Allow-Headers': 'Cache-Control',
-			'Content-Type': 'text/event-stream;charset=utf-8',
-			'Cache-Control': 'no-cache, no-transform',
-			'Connection': 'keep-alive',
-			// While behind nginx, event stream should not be buffered:
-			// http://nginx.org/docs/http/ngx_http_proxy_module.html#proxy_buffering
-			'X-Accel-Buffering': 'no'
+			event.process.stderr.on('data', data => {
+				process.stderr.write(data);
+			});
 		});
 
-		res.write('\n');
-
-		clients.add(res);
-		req.on('close', () => {
-			clients.delete(res);
-		});
-	});
-
-	server.listen(port);
-
-	function send(data: any) {
-		clients.forEach(client => {
-			client.write(`data: ${JSON.stringify(data)}\n\n`);
-		});
-	}
-
-	setInterval(() => {
-		send(null)
-	}, interval);
-
-	return { send };
-}
-
-export async function dev(opts: { port: number, open: boolean }) {
-	// remove this in a future version
-	const template = fs.readFileSync(path.join(locations.app(), 'template.html'), 'utf-8');
-	if (template.indexOf('%sapper.base%') === -1) {
-		console.log(`${clorox.bold.red(`> As of Sapper v0.10, your template.html file must include %sapper.base% in the <head>`)}`);
-		process.exit(1);
-	}
-
-	process.env.NODE_ENV = 'development';
-
-	let port = opts.port || +process.env.PORT;
-
-	if (port) {
-		if (!await ports.check(port)) {
-			console.log(`${clorox.bold.red(`> Port ${port} is unavailable`)}`);
-			return;
-		}
-	} else {
-		port = await ports.find(3000);
-	}
-
-	const dir = locations.dest();
-	rimraf.sync(dir);
-	mkdirp.sync(dir);
-
-	const dev_port = await ports.find(10000);
-
-	const routes = create_routes();
-	create_main_manifests({ routes, dev_port });
-
-	const hot_update_server = create_hot_update_server(dev_port);
-
-	watch_files(locations.routes(), ['add', 'unlink'], () => {
-		const routes = create_routes();
-		create_main_manifests({ routes, dev_port });
-	});
-
-	watch_files(`${locations.app()}/template.html`, ['change'], () => {
-		hot_update_server.send({
-			action: 'reload'
-		});
-	});
-
-	let proc: child_process.ChildProcess;
-
-	process.on('exit', () => {
-		// sometimes webpack crashes, so we need to kill our children
-		if (proc) proc.kill();
-	});
-
-	const deferreds = {
-		server: deferred(),
-		client: deferred()
-	};
-
-	let restarting = false;
-	let build = {
-		unique_warnings: new Set(),
-		unique_errors: new Set()
-	};
-
-	function restart_build(filename: string) {
-		if (restarting) return;
-
-		restarting = true;
-		build = {
-			unique_warnings: new Set(),
-			unique_errors: new Set()
-		};
-
-		process.nextTick(() => {
-			restarting = false;
+		watcher.on('invalid', (event: events.InvalidEvent) => {
+			const changed = event.changed.map(filename => path.relative(process.cwd(), filename)).join(', ');
+			console.log(`\n${colors.bold.cyan(changed)} changed. rebuilding...`);
 		});
 
-		console.log(`\n${clorox.bold.cyan(path.relative(process.cwd(), filename))} changed. rebuilding...`);
-	}
-
-	// TODO watch the configs themselves?
-	const compilers = create_compilers();
-
-	function watch(compiler: any, { name, invalid = noop, error = noop, result }: {
-		name: string,
-		invalid?: (filename: string) => void;
-		error?: (error: Error) => void;
-		result: (stats: any) => void;
-	}) {
-		compiler.hooks.invalid.tap('sapper', (filename: string) => {
-			invalid(filename);
+		watcher.on('error', (event: events.ErrorEvent) => {
+			console.log(`${colors.red(`✗ ${event.type}`)}`);
+			console.log(`${colors.red(event.error.message)}`);
 		});
 
-		compiler.watch({}, (err: Error, stats: any) => {
-			if (err) {
-				console.log(`${clorox.red(`✗ ${name}`)}`);
-				console.log(`${clorox.red(err.message)}`);
-				error(err);
-			} else {
-				const messages = format_messages(stats);
-				const info = stats.toJson();
+		watcher.on('fatal', (event: events.FatalEvent) => {
+			console.log(`${colors.bold.red(`> ${event.error.message}`)}`);
+		});
 
-				if (messages.errors.length > 0) {
-					console.log(`${clorox.bold.red(`✗ ${name}`)}`);
+		watcher.on('build', (event: events.BuildEvent) => {
+			if (event.errors.length) {
+				console.log(`${colors.bold.red(`✗ ${event.type}`)}`);
 
-					const filtered = messages.errors.filter((message: string) => {
-						return !build.unique_errors.has(message);
-					});
+				event.errors.filter(e => !e.duplicate).forEach(error => {
+					console.log(error.message);
+				});
 
-					filtered.forEach((message: string) => {
-						build.unique_errors.add(message);
-						console.log(message);
-					});
-
-					const hidden = messages.errors.length - filtered.length;
-					if (hidden > 0) {
-						console.log(`${hidden} duplicate ${hidden === 1 ? 'error' : 'errors'} hidden\n`);
-					}
-				} else {
-					if (messages.warnings.length > 0) {
-						console.log(`${clorox.bold.yellow(`• ${name}`)}`);
-
-						const filtered = messages.warnings.filter((message: string) => {
-							return !build.unique_warnings.has(message);
-						});
-
-						filtered.forEach((message: string) => {
-							build.unique_warnings.add(message);
-							console.log(`${message}\n`);
-						});
-
-						const hidden = messages.warnings.length - filtered.length;
-						if (hidden > 0) {
-							console.log(`${hidden} duplicate ${hidden === 1 ? 'warning' : 'warnings'} hidden\n`);
-						}
-					} else {
-						console.log(`${clorox.bold.green(`✔ ${name}`)} ${clorox.gray(`(${prettyMs(info.time)})`)}`);
-					}
-
-					result(info);
+				const hidden = event.errors.filter(e => e.duplicate).length;
+				if (hidden > 0) {
+					console.log(`${hidden} duplicate ${hidden === 1 ? 'error' : 'errors'} hidden\n`);
 				}
+			} else if (event.warnings.length) {
+				console.log(`${colors.bold.yellow(`• ${event.type}`)}`);
+
+				event.warnings.filter(e => !e.duplicate).forEach(warning => {
+					console.log(warning.message);
+				});
+
+				const hidden = event.warnings.filter(e => e.duplicate).length;
+				if (hidden > 0) {
+					console.log(`${hidden} duplicate ${hidden === 1 ? 'warning' : 'warnings'} hidden\n`);
+				}
+			} else {
+				console.log(`${colors.bold.green(`✔ ${event.type}`)} ${colors.gray(`(${prettyMs(event.duration)})`)}`);
 			}
 		});
+	} catch (err) {
+		console.log(`${colors.bold.red(`> ${err.message}`)}`);
+		process.exit(1);
 	}
-
-	watch(compilers.server, {
-		name: 'server',
-
-		invalid: filename => {
-			restart_build(filename);
-			// TODO print message
-			deferreds.server = deferred();
-		},
-
-		result: info => {
-			// TODO log compile errors/warnings
-
-			fs.writeFileSync(path.join(dir, 'server_info.json'), JSON.stringify(info, null, '  '));
-
-			deferreds.client.promise.then(() => {
-				function restart() {
-					ports.wait(port).then(deferreds.server.fulfil);
-				}
-
-				if (proc) {
-					proc.kill();
-					proc.on('exit', restart);
-				} else {
-					restart();
-				}
-
-				proc = child_process.fork(`${dir}/server.js`, [], {
-					cwd: process.cwd(),
-					env: Object.assign({
-						PORT: port
-					}, process.env)
-				});
-			});
-		}
-	});
-
-	let first = true;
-
-	watch(compilers.client, {
-		name: 'client',
-
-		invalid: filename => {
-			restart_build(filename);
-			deferreds.client = deferred();
-
-			// TODO we should delete old assets. due to a webpack bug
-			// i don't even begin to comprehend, this is apparently
-			// quite difficult
-		},
-
-		result: info => {
-			fs.writeFileSync(path.join(dir, 'client_info.json'), JSON.stringify({
-				assets: info.assetsByChunkName
-			}, null, '  '));
-			deferreds.client.fulfil();
-
-			const client_files = info.assets.map((chunk: { name: string }) => `client/${chunk.name}`);
-
-			deferreds.server.promise.then(() => {
-				hot_update_server.send({
-					status: 'completed'
-				});
-
-				if (first) {
-					first = false;
-					console.log(`${clorox.bold.cyan(`> Listening on http://localhost:${port}`)}`);
-					if (opts.open) child_process.exec(`open http://localhost:${port}`);
-				}
-			});
-
-			create_serviceworker_manifest({
-				routes: create_routes(),
-				client_files
-			});
-
-			watch_serviceworker();
-		}
-	});
-
-	let watch_serviceworker = compilers.serviceworker
-		? function() {
-			watch_serviceworker = noop;
-
-			watch(compilers.serviceworker, {
-				name: 'service worker',
-
-				result: info => {
-					fs.writeFileSync(path.join(dir, 'serviceworker_info.json'), JSON.stringify(info, null, '  '));
-				}
-			});
-		}
-		: noop;
-}
-
-function noop() {}
-
-function watch_files(pattern: string, events: string[], callback: () => void) {
-	const chokidar = require('chokidar');
-
-	const watcher = chokidar.watch(pattern, {
-		persistent: true,
-		ignoreInitial: true,
-		disableGlobbing: true
-	});
-
-	events.forEach(event => {
-		watcher.on(event, callback);
-	});
-}
+}

src/cli/export.ts

@@ -1,106 +1,35 @@
-import * as child_process from 'child_process';
-import * as path from 'path';
-import * as sander from 'sander';
-import * as clorox from 'clorox';
-import cheerio from 'cheerio';
-import URL from 'url-parse';
-import fetch from 'node-fetch';
-import * as ports from 'port-authority';
+import { exporter as _exporter } from '../api/export';
+import * as colors from 'ansi-colors';
 import prettyBytes from 'pretty-bytes';
-import { minify_html } from './utils/minify_html';
 import { locations } from '../config';
 
-export async function exporter(export_dir: string, { basepath = '' }) {
-	const build_dir = locations.dest();
+export function exporter(export_dir: string, { basepath = '' }) {
+	return new Promise((fulfil, reject) => {
+		try {
+			const emitter = _exporter({
+				build: locations.dest(),
+				dest: export_dir,
+				basepath
+			});
 
-	export_dir = path.join(export_dir, basepath);
+			emitter.on('file', event => {
+				console.log(`${colors.bold.cyan(event.file)} ${colors.gray(`(${prettyBytes(event.size)})`)}`);
+			});
 
-	// Prep output directory
-	sander.rimrafSync(export_dir);
+			emitter.on('failure', event => {
+				console.log(`${colors.red(`> Received ${event.status} response when fetching ${event.pathname}`)}`);
+			});
 
-	sander.copydirSync('assets').to(export_dir);
-	sander.copydirSync(build_dir, 'client').to(export_dir, 'client');
+			emitter.on('error', event => {
+				reject(event.error);
+			});
 
-	if (sander.existsSync(build_dir, 'service-worker.js')) {
-		sander.copyFileSync(build_dir, 'service-worker.js').to(export_dir, 'service-worker.js');
-	}
-
-	if (sander.existsSync(build_dir, 'service-worker.js.map')) {
-		sander.copyFileSync(build_dir, 'service-worker.js.map').to(export_dir, 'service-worker.js.map');
-	}
-
-	const port = await ports.find(3000);
-
-	const origin = `http://localhost:${port}`;
-
-	const proc = child_process.fork(path.resolve(`${build_dir}/server.js`), [], {
-		cwd: process.cwd(),
-		env: Object.assign({
-			PORT: port,
-			NODE_ENV: 'production',
-			SAPPER_DEST: build_dir,
-			SAPPER_EXPORT: 'true'
-		}, process.env)
+			emitter.on('done', event => {
+				fulfil();
+			});
+		} catch (err) {
+			console.log(`${colors.bold.red(`> ${err.message}`)}`);
+			process.exit(1);
+		}
 	});
-
-	const seen = new Set();
-	const saved = new Set();
-
-	proc.on('message', message => {
-		if (!message.__sapper__) return;
-
-		let file = new URL(message.url, origin).pathname.slice(1);
-		let { body } = message;
-
-		if (saved.has(file)) return;
-		saved.add(file);
-
-		const is_html = message.type === 'text/html';
-
-		if (is_html) {
-			file = file === '' ? 'index.html' : `${file}/index.html`;
-			body = minify_html(body);
-		}
-
-		console.log(`${clorox.bold.cyan(file)} ${clorox.gray(`(${prettyBytes(body.length)})`)}`);
-
-		sander.writeFileSync(export_dir, file, body);
-	});
-
-	async function handle(url: URL) {
-		const r = await fetch(url.href);
-		const range = ~~(r.status / 100);
-
-		if (range >= 4) {
-			console.log(`${clorox.red(`> Received ${r.status} response when fetching ${url.pathname}`)}`);
-			return;
-		}
-
-		if (range === 2) {
-			if (r.headers.get('Content-Type') === 'text/html') {
-				const body = await r.text();
-				const $ = cheerio.load(body);
-				const urls: URL[] = [];
-
-				const base = new URL($('base').attr('href') || '/', url.href);
-
-				$('a[href]').each((i: number, $a) => {
-					const url = new URL($a.attribs.href, base.href);
-
-					if (url.origin === origin && !seen.has(url.pathname)) {
-						seen.add(url.pathname);
-						urls.push(url);
-					}
-				});
-
-				for (const url of urls) {
-					await handle(url);
-				}
-			}
-		}
-	}
-
-	return ports.wait(port)
-		.then(() => handle(new URL(`/${basepath}`, origin))) // TODO all static routes
-		.then(() => proc.kill());
-}
+}

src/cli/start.ts

@@ -1,7 +1,7 @@
 import * as fs from 'fs';
 import * as path from 'path';
 import * as child_process from 'child_process';
-import * as clorox from 'clorox';
+import * as colors from 'ansi-colors';
 import * as ports from 'port-authority';
 
 export async function start(dir: string, opts: { port: number, open: boolean }) {
@@ -11,13 +11,13 @@ export async function start(dir: string, opts: { port: number, open: boolean })
 	const server = path.resolve(dir, 'server.js');
 
 	if (!fs.existsSync(server)) {
-		console.log(`${clorox.bold.red(`> ${dir}/server.js does not exist — type ${clorox.bold.cyan(dir === 'build' ? `npx sapper build` : `npx sapper build ${dir}`)} to create it`)}`);
+		console.log(`${colors.bold.red(`> ${dir}/server.js does not exist — type ${colors.bold.cyan(dir === 'build' ? `npx sapper build` : `npx sapper build ${dir}`)} to create it`)}`);
 		return;
 	}
 
 	if (port) {
 		if (!await ports.check(port)) {
-			console.log(`${clorox.bold.red(`> Port ${port} is unavailable`)}`);
+			console.log(`${colors.bold.red(`> Port ${port} is unavailable`)}`);
 			return;
 		}
 	} else {
@@ -34,6 +34,6 @@ export async function start(dir: string, opts: { port: number, open: boolean })
 	});
 
 	await ports.wait(port);
-	console.log(`${clorox.bold.cyan(`> Listening on http://localhost:${port}`)}`);
+	console.log(`${colors.bold.cyan(`> Listening on http://localhost:${port}`)}`);
 	if (opts.open) child_process.exec(`open http://localhost:${port}`);
-}
+}

src/cli/upgrade.ts

@@ -1,5 +1,5 @@
 import * as fs from 'fs';
-import * as clorox from 'clorox';
+import * as colors from 'ansi-colors';
 
 export default async function upgrade() {
 	const upgraded = [
@@ -27,10 +27,10 @@ async function upgrade_sapper_main() {
 
 		if (/\%sapper\.main\%/.test(template)) {
 			if (!pattern.test(template)) {
-				console.log(`${clorox.red(`Could not replace %sapper.main% in ${file}`)}`);
+				console.log(`${colors.red(`Could not replace %sapper.main% in ${file}`)}`);
 			} else {
 				write(file, template.replace(pattern, `%sapper.scripts%`));
-				console.log(`${clorox.green(`Replaced %sapper.main% in ${file}`)}`);
+				console.log(`${colors.green(`Replaced %sapper.main% in ${file}`)}`);
 				replaced = true;
 			}
 		}

src/core/create_compilers.ts

@@ -1,21 +1,21 @@
 import * as path from 'path';
 import relative from 'require-relative';
 
-export default function create_compilers() {
-	const webpack = relative('webpack', process.cwd());
+export default function create_compilers({ webpack }: { webpack: string }) {
+	const wp = relative('webpack', process.cwd());
 
-	const serviceworker_config = try_require(path.resolve('webpack/service-worker.config.js'));
+	const serviceworker_config = try_require(path.resolve(`${webpack}/service-worker.config.js`));
 
 	return {
-		client: webpack(
-			require(path.resolve('webpack/client.config.js'))
+		client: wp(
+			require(path.resolve(`${webpack}/client.config.js`))
 		),
 
-		server: webpack(
-			require(path.resolve('webpack/server.config.js'))
+		server: wp(
+			require(path.resolve(`${webpack}/server.config.js`))
 		),
 
-		serviceworker: serviceworker_config && webpack(serviceworker_config)
+		serviceworker: serviceworker_config && wp(serviceworker_config)
 	};
 }
 

src/core/create_manifests.ts

@@ -1,7 +1,6 @@
 import * as fs from 'fs';
 import * as path from 'path';
 import * as glob from 'glob';
-import create_routes from './create_routes';
 import { posixify, write_if_changed } from './utils';
 import { dev, locations } from '../config';
 import { Route } from '../interfaces';

src/core/create_routes.ts

@@ -30,12 +30,10 @@ export default function create_routes({ files } = { files: glob.sync('**/*.*', {
 			return !found;
 		})
 		.sort((a, b) => {
-			const max = Math.max(a.parts.length, b.parts.length);
+			if (a.parts[0] === '4xx' || a.parts[0] === '5xx') return -1;
+			if (b.parts[0] === '4xx' || b.parts[0] === '5xx') return 1;
 
-			if (max === 1) {
-				if (a.parts[0] === '4xx' || a.parts[0] === '5xx') return -1;
-				if (b.parts[0] === '4xx' || b.parts[0] === '5xx') return 1;
-			}
+			const max = Math.max(a.parts.length, b.parts.length);
 
 			for (let i = 0; i < max; i += 1) {
 				const a_part = a.parts[i];

src/middleware.ts

@@ -8,7 +8,6 @@ import rimraf from 'rimraf';
 import devalue from 'devalue';
 import fetch from 'node-fetch';
 import { lookup } from './middleware/mime';
-import { create_routes, create_compilers } from './core';
 import { locations, dev } from './config';
 import { Route, Template } from './interfaces';
 import sourceMapSupport from 'source-map-support';
@@ -20,14 +19,7 @@ type RouteObject = {
 	type: 'page' | 'route';
 	pattern: RegExp;
 	params: (match: RegExpMatchArray) => Record<string, string>;
-	module: {
-		render: (data: any, opts: { store: Store }) => {
-			head: string;
-			css: { code: string, map: any };
-			html: string
-		},
-		preload: (data: any) => any | Promise<any>
-	};
+	module: Component;
 	error?: string;
 }
 
@@ -47,13 +39,27 @@ interface Req extends ClientRequest {
 	headers: Record<string, string>;
 }
 
-export default function middleware({ routes, store }: {
+interface Component {
+	render: (data: any, opts: { store: Store }) => {
+		head: string;
+		css: { code: string, map: any };
+		html: string
+	},
+	preload: (data: any) => any | Promise<any>
+}
+
+export default function middleware({ App, routes, store }: {
+	App: Component,
 	routes: RouteObject[],
 	store: (req: Req) => Store
 }) {
+	if (!App) {
+		throw new Error(`As of 0.12, you must supply an App component to Sapper — see https://sapper.svelte.technology/guide#0-11-to-0-12 for more information`);
+	}
+
 	const output = locations.dest();
 
-	const client_info = JSON.parse(fs.readFileSync(path.join(output, 'client_info.json'), 'utf-8'));
+	const client_assets = JSON.parse(fs.readFileSync(path.join(output, 'client_assets.json'), 'utf-8'));
 
 	const middleware = compose_handlers([
 		(req: Req, res: ServerResponse, next: () => void) => {
@@ -90,7 +96,7 @@ export default function middleware({ routes, store }: {
 			cache_control: 'max-age=31536000'
 		}),
 
-		get_route_handler(client_info.assets, routes, store)
+		get_route_handler(client_assets, App, routes, store)
 	].filter(Boolean));
 
 	return middleware;
@@ -135,7 +141,7 @@ function serve({ prefix, pathname, cache_control }: {
 
 const resolved = Promise.resolve();
 
-function get_route_handler(chunks: Record<string, string>, routes: RouteObject[], store_getter: (req: Req) => Store) {
+function get_route_handler(chunks: Record<string, string>, App: Component, routes: RouteObject[], store_getter: (req: Req) => Store) {
 	const template = dev()
 		? () => fs.readFileSync(`${locations.app()}/template.html`, 'utf-8')
 		: (str => () => str)(fs.readFileSync(`${locations.dest()}/template.html`, 'utf-8'));
@@ -170,7 +176,7 @@ function get_route_handler(chunks: Record<string, string>, routes: RouteObject[]
 					res.setHeader('Link', link);
 
 					const store = store_getter ? store_getter(req) : null;
-					const data = { params: req.params, query: req.query };
+					const props = { params: req.params, query: req.query, path: req.path };
 
 					let redirect: { statusCode: number, location: string };
 					let error: { statusCode: number, message: Error | string };
@@ -240,9 +246,9 @@ function get_route_handler(chunks: Record<string, string>, routes: RouteObject[]
 							preloaded: mod.preload && try_serialize(preloaded),
 							store: store && try_serialize(store.get())
 						};
-						Object.assign(data, preloaded);
+						Object.assign(props, preloaded);
 
-						const { html, head, css } = mod.render(data, {
+						const { html, head, css } = App.render({ Page: mod, props }, {
 							store
 						});
 

src/runtime/index.ts

@@ -3,6 +3,7 @@ import { Component, ComponentConstructor, Params, Query, Route, RouteData, Scrol
 
 const manifest = typeof window !== 'undefined' && window.__SAPPER__;
 
+export let App: ComponentConstructor;
 export let component: Component;
 let target: Node;
 let store: Store;
@@ -27,10 +28,10 @@ function select_route(url: URL): Target {
 	if (url.origin !== window.location.origin) return null;
 	if (!url.pathname.startsWith(manifest.baseUrl)) return null;
 
-	const pathname = url.pathname.slice(manifest.baseUrl.length);
+	const path = url.pathname.slice(manifest.baseUrl.length);
 
 	for (const route of routes) {
-		const match = route.pattern.exec(pathname);
+		const match = route.pattern.exec(path);
 		if (match) {
 			if (route.ignore) return null;
 
@@ -43,18 +44,24 @@ function select_route(url: URL): Target {
 					query[key] = value || true;
 				})
 			}
-			return { url, route, data: { params, query } };
+			return { url, route, props: { params, query, path } };
 		}
 	}
 }
 
 let current_token: {};
 
-function render(Component: ComponentConstructor, data: any, scroll: ScrollPosition, token: {}) {
+function render(Page: ComponentConstructor, props: any, scroll: ScrollPosition, token: {}) {
 	if (current_token !== token) return;
 
+	const data = {
+		Page,
+		props,
+		preloading: false
+	};
+
 	if (component) {
-		component.destroy();
+		component.set(data);
 	} else {
 		// first load — remove SSR'd <head> contents
 		const start = document.querySelector('#sapper-head-start');
@@ -65,33 +72,39 @@ function render(Component: ComponentConstructor, data: any, scroll: ScrollPositi
 			detach(start);
 			detach(end);
 		}
-	}
 
-	component = new Component({
-		target,
-		data,
-		store,
-		hydrate: !component
-	});
+		component = new App({
+			target,
+			data,
+			store,
+			hydrate: true
+		});
+	}
 
 	if (scroll) {
 		window.scrollTo(scroll.x, scroll.y);
 	}
 }
 
-function prepare_route(Component: ComponentConstructor, data: RouteData) {
+function prepare_route(Page: ComponentConstructor, props: RouteData) {
 	let redirect: { statusCode: number, location: string } = null;
 	let error: { statusCode: number, message: Error | string } = null;
 
-	if (!Component.preload) {
-		return { Component, data, redirect, error };
+	if (!Page.preload) {
+		return { Page, props, redirect, error };
 	}
 
 	if (!component && manifest.preloaded) {
-		return { Component, data: Object.assign(data, manifest.preloaded), redirect, error };
+		return { Page, props: Object.assign(props, manifest.preloaded), redirect, error };
 	}
 
-	return Promise.resolve(Component.preload.call({
+	if (component) {
+		component.set({
+			preloading: true
+		});
+	}
+
+	return Promise.resolve(Page.preload.call({
 		store,
 		fetch: (url: string, opts?: any) => window.fetch(url, opts),
 		redirect: (statusCode: number, location: string) => {
@@ -100,7 +113,7 @@ function prepare_route(Component: ComponentConstructor, data: RouteData) {
 		error: (statusCode: number, message: Error | string) => {
 			error = { statusCode, message };
 		}
-	}, data)).catch(err => {
+	}, props)).catch(err => {
 		error = { statusCode: 500, message: err };
 	}).then(preloaded => {
 		if (error) {
@@ -108,15 +121,15 @@ function prepare_route(Component: ComponentConstructor, data: RouteData) {
 				? errors['4xx']
 				: errors['5xx'];
 
-			return route.load().then(({ default: Component }: { default: ComponentConstructor }) => {
+			return route.load().then(({ default: Page }: { default: ComponentConstructor }) => {
 				const err = error.message instanceof Error ? error.message : new Error(error.message);
-				Object.assign(data, { status: error.statusCode, error: err });
-				return { Component, data, redirect: null };
+				Object.assign(props, { status: error.statusCode, error: err });
+				return { Page, props, redirect: null };
 			});
 		}
 
-		Object.assign(data, preloaded)
-		return { Component, data, redirect };
+		Object.assign(props, preloaded)
+		return { Page, props, redirect };
 	});
 }
 
@@ -136,18 +149,18 @@ function navigate(target: Target, id: number) {
 
 	const loaded = prefetching && prefetching.href === target.url.href ?
 		prefetching.promise :
-		target.route.load().then(mod => prepare_route(mod.default, target.data));
+		target.route.load().then(mod => prepare_route(mod.default, target.props));
 
 	prefetching = null;
 
 	const token = current_token = {};
 
-	return loaded.then(({ Component, data, redirect }) => {
+	return loaded.then(({ Page, props, redirect }) => {
 		if (redirect) {
 			return goto(redirect.location, { replaceState: true });
 		}
 
-		render(Component, data, scroll_history[id], token);
+		render(Page, props, scroll_history[id], token);
 	});
 }
 
@@ -208,7 +221,7 @@ function handle_popstate(event: PopStateEvent) {
 
 let prefetching: {
 	href: string;
-	promise: Promise<{ Component: ComponentConstructor, data: any }>;
+	promise: Promise<{ Page: ComponentConstructor, props: any }>;
 } = null;
 
 export function prefetch(href: string) {
@@ -217,7 +230,7 @@ export function prefetch(href: string) {
 	if (selected && (!prefetching || href !== prefetching.href)) {
 		prefetching = {
 			href,
-			promise: selected.route.load().then(mod => prepare_route(mod.default, selected.data))
+			promise: selected.route.load().then(mod => prepare_route(mod.default, selected.props))
 		};
 	}
 }
@@ -240,12 +253,17 @@ function trigger_prefetch(event: MouseEvent | TouchEvent) {
 
 let inited: boolean;
 
-export function init(_target: Node, _routes: Route[], opts?: { store?: (data: any) => Store }) {
-	target = _target;
-	routes = _routes.filter(r => !r.error);
+export function init(opts: { App: ComponentConstructor, target: Node, routes: Route[], store?: (data: any) => Store }) {
+	if (opts instanceof HTMLElement) {
+		throw new Error(`The signature of init(...) has changed — see https://sapper.svelte.technology/guide#0-11-to-0-12 for more information`);
+	}
+
+	App = opts.App;
+	target = opts.target;
+	routes = opts.routes.filter(r => !r.error);
 	errors = {
-		'4xx': _routes.find(r => r.error === '4xx'),
-		'5xx': _routes.find(r => r.error === '5xx')
+		'4xx': opts.routes.find(r => r.error === '4xx'),
+		'5xx': opts.routes.find(r => r.error === '5xx')
 	};
 
 	if (opts && opts.store) {

src/runtime/interfaces.ts

@@ -3,11 +3,11 @@ import { Store } from '../interfaces';
 export { Store };
 export type Params = Record<string, string>;
 export type Query = Record<string, string | true>;
-export type RouteData = { params: Params, query: Query };
+export type RouteData = { params: Params, query: Query, path: string };
 
 export interface ComponentConstructor {
 	new (options: { target: Node, data: any, store: Store, hydrate: boolean }): Component;
-	preload: (data: { params: Params, query: Query }) => Promise<any>;
+	preload: (props: { params: Params, query: Query }) => Promise<any>;
 };
 
 export interface Component {
@@ -30,5 +30,5 @@ export type ScrollPosition = {
 export type Target = {
 	url: URL;
 	route: Route;
-	data: RouteData;
+	props: RouteData;
 };

test/app/app/App.html

@@ -0,0 +1,6 @@
+{#if preloading}
+	<progress class='preloading-progress' value=0.5/>
+{/if}
+
+<svelte:component this={Page} {...props}/>
+

test/app/app/client.js

@@ -1,9 +1,13 @@
 import { init, prefetchRoutes } from '../../../runtime.js';
 import { Store } from 'svelte/store.js';
 import { routes } from './manifest/client.js';
+import App from './App.html';
 
 window.init = () => {
-	return init(document.querySelector('#sapper'), routes, {
+	return init({
+		target: document.querySelector('#sapper'),
+		App,
+		routes,
 		store: data => new Store(data)
 	});
 };

test/app/app/server.js

@@ -5,6 +5,7 @@ import serve from 'serve-static';
 import sapper from '../../../dist/middleware.ts.js';
 import { Store } from 'svelte/store.js';
 import { routes } from './manifest/server.js';
+import App from './App.html'
 
 let pending;
 let ended;
@@ -86,6 +87,7 @@ const middlewares = [
 	},
 
 	sapper({
+		App,
 		routes,
 		store: () => {
 			return new Store({

test/common/test.js

@@ -574,6 +574,29 @@ function run({ mode, basepath = '' }) {
 					assert.ok(html.indexOf('service-worker.js') !== -1);
 				});
 			});
+
+			it('sets preloading true when appropriate', () => {
+				return nightmare
+					.goto(base)
+					.init()
+					.click('a[href="slow-preload"]')
+					.wait(100)
+					.evaluate(() => {
+						const progress = document.querySelector('progress');
+						return !!progress;
+					})
+					.then(hasProgressIndicator => {
+						assert.ok(hasProgressIndicator);
+					})
+					.then(() => nightmare.evaluate(() => window.fulfil()))
+					.then(() => nightmare.evaluate(() => {
+						const progress = document.querySelector('progress');
+						return !!progress;
+					}))
+					.then(hasProgressIndicator => {
+						assert.ok(!hasProgressIndicator);
+					});
+			});
 		});
 
 		describe('headers', () => {