[feat] adapter module

documentation/docs/80-adapter-api.md

@@ -23,15 +23,17 @@ export default function (options) {
 
 The types for `Adapter` and its parameters are available in [types/config.d.ts](https://github.com/sveltejs/kit/blob/master/packages/kit/types/config.d.ts).
 
-Within the `adapt` method, there are a number of things that an adapter should do:
+Within the `adapt` method, an adapter should
 
 - Clear out the build directory
-- Output code that:
- - Calls `init`
- - Converts from the platform's request to a [SvelteKit request](#hooks-handle), calls `render`, and converts from a [SvelteKit response](#hooks-handle) to the platform's
- - Globally shims `fetch` to work on the target platform. SvelteKit provides a `@sveltejs/kit/install-fetch` helper for platforms that can use `node-fetch`
+- Import `{ appResolver }` from `@sveltejs/kit/adapter`
+- Pass in `appResolver()` to esbuild plugins for build options
+- Import `app` from `@sveltejs/kit/app`
+- Calls `app.init()`
+- Converts from the platform's request to a [SvelteKit request](#hooks-handle), calls `app.render()`, and converts from a [SvelteKit response](#hooks-handle) to the platform's
+- Globally shims `fetch` to work on the target platform. SvelteKit provides a `@sveltejs/kit/install-fetch` helper for platforms that can use `node-fetch`
 - Bundle the output to avoid needing to install dependencies on the target platform, if desired
-- Call `utils.prerender`
+- Call `utils.prerender()`
 - Put the user's static files and the generated JS/CSS in the correct location for the target platform
 
 If possible, we recommend putting the adapter output under the `build/` directory with any intermediate output placed under `'.svelte-kit/' + adapterName`.

packages/adapter-cloudflare-workers/files/entry.js

@@ -1,5 +1,4 @@
-// TODO hardcoding the relative location makes this brittle
-import { init, render } from '../output/server/app.js';
+import { init, render } from '@sveltejs/kit/app';
 import { getAssetFromKV, NotFoundError } from '@cloudflare/kv-asset-handler';
 
 init();

packages/adapter-cloudflare-workers/index.js

@@ -1,9 +1,11 @@
-import fs from 'fs';
 import { execSync } from 'child_process';
-import esbuild from 'esbuild';
-import toml from '@iarna/toml';
+import fs from 'fs';
 import { fileURLToPath } from 'url';
 
+import toml from '@iarna/toml';
+import { appResolver } from '@sveltejs/kit/adapter';
+import esbuild from 'esbuild';
+
 /**
  * @typedef {import('esbuild').BuildOptions} BuildOptions
  */
@@ -40,7 +42,8 @@ export default function (options) {
  outfile: `${entrypoint}/index.js`,
  bundle: true,
  target: 'es2020',
- platform: 'browser'
+ platform: 'browser',
+ plugins: [appResolver()]
  };
 
  const build_options =

packages/adapter-netlify/files/entry.js

@@ -1,5 +1,4 @@
-// TODO hardcoding the relative location makes this brittle
-import { init, render } from '../output/server/app.js';
+import { init, render } from '@sveltejs/kit/app';
 
 init();
 

packages/adapter-netlify/index.js

@@ -1,8 +1,10 @@
-import { appendFileSync, existsSync, readFileSync, writeFileSync } from 'fs';
+import fs from 'fs';
 import { join, resolve } from 'path';
 import { fileURLToPath } from 'url';
-import esbuild from 'esbuild';
+
 import toml from '@iarna/toml';
+import { appResolver } from '@sveltejs/kit/adapter';
+import esbuild from 'esbuild';
 
 /**
  * @typedef {import('esbuild').BuildOptions} BuildOptions
@@ -34,6 +36,7 @@ export default function (options) {
  outfile: '.netlify/functions-internal/__render.js',
  bundle: true,
  inject: [join(files, 'shims.js')],
+ plugins: [appResolver()],
  platform: 'node'
  };
 
@@ -42,7 +45,7 @@ export default function (options) {
 
  await esbuild.build(build_options);
 
- writeFileSync(join('.netlify', 'package.json'), JSON.stringify({ type: 'commonjs' }));
+ fs.writeFileSync(join('.netlify', 'package.json'), JSON.stringify({ type: 'commonjs' }));
 
  utils.log.minor('Prerendering static pages...');
  await utils.prerender({
@@ -57,20 +60,20 @@ export default function (options) {
 
  const redirectPath = join(publish, '_redirects');
  utils.copy('_redirects', redirectPath);
- appendFileSync(redirectPath, '\n\n/* /.netlify/functions/__render 200');
+ fs.appendFileSync(redirectPath, '\n\n/* /.netlify/functions/__render 200');
  }
  };
 }
 /**
  * @param {import('@sveltejs/kit').AdapterUtils} utils
  **/
 function get_publish_directory(utils) {
- if (existsSync('netlify.toml')) {
+ if (fs.existsSync('netlify.toml')) {
  /** @type {{ build?: { publish?: string }} & toml.JsonMap } */
  let netlify_config;
 
  try {
- netlify_config = toml.parse(readFileSync('netlify.toml', 'utf-8'));
+ netlify_config = toml.parse(fs.readFileSync('netlify.toml', 'utf-8'));
  } catch (err) {
  err.message = `Error parsing netlify.toml: ${err.message}`;
  throw err;

packages/adapter-node/index.js

@@ -1,17 +1,12 @@
-import esbuild from 'esbuild';
-import {
- createReadStream,
- createWriteStream,
- existsSync,
- readFileSync,
- statSync,
- writeFileSync
-} from 'fs';
+import fs from 'fs';
 import { join } from 'path';
 import { pipeline } from 'stream';
-import glob from 'tiny-glob';
 import { fileURLToPath } from 'url';
 import { promisify } from 'util';
+
+import { appResolver } from '@sveltejs/kit/adapter';
+import esbuild from 'esbuild';
+import glob from 'tiny-glob';
 import zlib from 'zlib';
 
 const pipe = promisify(pipeline);
@@ -25,7 +20,7 @@ export default function ({
  out = 'build',
  precompress,
  env: { path: path_env = 'SOCKET_PATH', host: host_env = 'HOST', port: port_env = 'PORT' } = {},
- esbuild: esbuildConfig
+ esbuild: esbuild_config
 } = {}) {
  return {
  name: '@sveltejs/adapter-node',
@@ -44,8 +39,8 @@ export default function ({
  utils.log.minor('Building SvelteKit middleware');
  const files = fileURLToPath(new URL('./files', import.meta.url));
  utils.copy(files, '.svelte-kit/node');
- writeFileSync(
- '.svelte-kit/node/env.js',
+ fs.writeFileSync(
+ '.svelte-kit/node/env.js', // types pointed in src/env.d.ts
  `export const path = process.env[${JSON.stringify(
  path_env
  )}] || false;\nexport const host = process.env[${JSON.stringify(
@@ -56,25 +51,27 @@ export default function ({
  );
 
  /** @type {BuildOptions} */
- const defaultOptions = {
+ const default_options = {
  entryPoints: ['.svelte-kit/node/middlewares.js'],
  outfile: join(out, 'middlewares.js'),
  bundle: true,
- external: Object.keys(JSON.parse(readFileSync('package.json', 'utf8')).dependencies || {}),
+ external: Object.keys(
+ JSON.parse(fs.readFileSync('package.json', 'utf8')).dependencies || {}
+ ),
  format: 'esm',
  platform: 'node',
  target: 'node12',
  inject: [join(files, 'shims.js')],
+ plugins: [appResolver()],
  define: {
  APP_DIR: `"/${config.kit.appDir}/"`
  }
  };
- const buildOptions = esbuildConfig ? await esbuildConfig(defaultOptions) : defaultOptions;
- await esbuild.build(buildOptions);
+ await esbuild.build(esbuild_config ? await esbuild_config(default_options) : default_options);
 
  utils.log.minor('Building SvelteKit reference server');
  /** @type {BuildOptions} */
- const defaultOptionsRefServer = {
+ const ref_server_options = {
  entryPoints: ['.svelte-kit/node/index.js'],
  outfile: join(out, 'index.js'),
  bundle: true,
@@ -93,16 +90,15 @@ export default function ({
  }
  ]
  };
- const buildOptionsRefServer = esbuildConfig
- ? await esbuildConfig(defaultOptionsRefServer)
- : defaultOptionsRefServer;
- await esbuild.build(buildOptionsRefServer);
+ await esbuild.build(
+ esbuild_config ? await esbuild_config(ref_server_options) : ref_server_options
+ );
 
  utils.log.minor('Prerendering static pages');
  await utils.prerender({
  dest: `${out}/prerendered`
  });
- if (precompress && existsSync(`${out}/prerendered`)) {
+ if (precompress && fs.existsSync(`${out}/prerendered`)) {
  utils.log.minor('Compressing prerendered pages');
  await compress(`${out}/prerendered`);
  }
@@ -137,13 +133,13 @@ async function compress_file(file, format = 'gz') {
  params: {
  [zlib.constants.BROTLI_PARAM_MODE]: zlib.constants.BROTLI_MODE_TEXT,
  [zlib.constants.BROTLI_PARAM_QUALITY]: zlib.constants.BROTLI_MAX_QUALITY,
- [zlib.constants.BROTLI_PARAM_SIZE_HINT]: statSync(file).size
+ [zlib.constants.BROTLI_PARAM_SIZE_HINT]: fs.statSync(file).size
  }
  })
  : zlib.createGzip({ level: zlib.constants.Z_BEST_COMPRESSION });
 
- const source = createReadStream(file);
- const destination = createWriteStream(`${file}.${format}`);
+ const source = fs.createReadStream(file);
+ const destination = fs.createWriteStream(`${file}.${format}`);
 
  await pipe(source, compress, destination);
 }

packages/adapter-node/rollup.config.js

@@ -21,7 +21,12 @@ export default [
  sourcemap: true
  },
  plugins: [nodeResolve(), commonjs(), json()],
- external: ['./middlewares.js', './env.js', ...require('module').builtinModules]
+ external: [
+ '@sveltejs/kit/app',
+ './middlewares.js',
+ './env.js',
+ ...require('module').builtinModules
+ ]
  },
  {
  input: 'src/shims.js',

packages/adapter-node/src/env.d.ts

@@ -0,0 +1,3 @@
+export const host: string;
+export const path: string;
+export const port: number;

packages/adapter-node/src/index.js

@@ -1,4 +1,3 @@
-// @ts-ignore
 import { path, host, port } from './env.js';
 import { assetsMiddleware, kitMiddleware, prerenderedMiddleware } from './middlewares.js';
 import compression from 'compression';

packages/adapter-node/src/kit-middleware.js

@@ -1,10 +1,9 @@
 import { getRawBody } from '@sveltejs/kit/node';
 
 /**
+ * @param {import('@sveltejs/kit').App} app
  * @return {import('polka').Middleware}
  */
-// TODO: type render function from @sveltejs/kit/adapter
-// @ts-ignore
 export function create_kit_middleware({ render }) {
  return async (req, res) => {
  const parsed = new URL(req.url || '', 'http://localhost');
@@ -20,7 +19,8 @@ export function create_kit_middleware({ render }) {
 
  const rendered = await render({
  method: req.method,
- headers: req.headers, // TODO: what about repeated headers, i.e. string[]
+ // @ts-expect-error - TODO: what about repeated headers, i.e. string[]
+ headers: req.headers,
  path: parsed.pathname,
  query: parsed.searchParams,
  rawBody: body

packages/adapter-node/src/middlewares.js

@@ -1,16 +1,12 @@
-// TODO hardcoding the relative location makes this brittle
-// Also, we need most of the logic in another file for testing because
-// ../output/server/app.js doesn't exist when we run the tests
-// @ts-ignore
-import { init, render } from '../output/server/app.js';
-import { create_kit_middleware } from './kit-middleware.js';
-
 import fs from 'fs';
 import { dirname, join } from 'path';
-import sirv from 'sirv';
 import { fileURLToPath } from 'url';
 
-// App is a dynamic file built from the application layer.
+import app from '@sveltejs/kit/app';
+import sirv from 'sirv';
+import { create_kit_middleware } from './kit-middleware.js';
+
+app.init();
 
 const __dirname = dirname(fileURLToPath(import.meta.url));
 /** @type {import('polka').Middleware} */
@@ -42,7 +38,4 @@ export const assetsMiddleware = fs.existsSync(paths.assets)
  })
  : noop_handler;
 
-export const kitMiddleware = (function () {
- init();
- return create_kit_middleware({ render });
-})();
+export const kitMiddleware = create_kit_middleware(app);

packages/adapter-vercel/files/entry.js

@@ -1,8 +1,6 @@
+import { init, render } from '@sveltejs/kit/app';
 import { getRawBody } from '@sveltejs/kit/node';
 
-// TODO hardcoding the relative location makes this brittle
-import { init, render } from '../output/server/app.js';
-
 init();
 
 export default async (req, res) => {

packages/adapter-vercel/index.js

@@ -1,6 +1,8 @@
 import { writeFileSync } from 'fs';
 import { join } from 'path';
 import { fileURLToPath } from 'url';
+
+import { appResolver } from '@sveltejs/kit/adapter';
 import esbuild from 'esbuild';
 
 /**
@@ -37,6 +39,7 @@ export default function (options) {
  outfile: join(dirs.lambda, 'index.js'),
  bundle: true,
  inject: [join(files, 'shims.js')],
+ plugins: [appResolver()],
  platform: 'node'
  };
 

packages/kit/package.json

@@ -21,6 +21,7 @@
  "amphtml-validator": "^1.0.34",
  "cookie": "^0.4.1",
  "devalue": "^2.0.1",
+ "esbuild": "^0.12.5",
  "eslint": "^7.25.0",
  "kleur": "^4.1.4",
  "locate-character": "^2.0.5",
@@ -66,6 +67,9 @@
  },
  "exports": {
  "./package.json": "./package.json",
+ "./adapter": {
+ "import": "./dist/adapter.js"
+ },
  "./ssr": {
  "import": "./dist/ssr.js"
  },

packages/kit/rollup.config.js

@@ -46,6 +46,7 @@ export default [
  {
  input: {
  cli: 'src/cli.js',
+ adapter: 'src/core/adapt/plugins.js',
  ssr: 'src/runtime/server/index.js',
  node: 'src/core/node/index.js',
  hooks: 'src/runtime/hooks.js',

packages/kit/src/core/adapt/plugins.js

@@ -0,0 +1,13 @@
+import { join } from 'path';
+
+/** @type {import('@sveltejs/kit/adapter').AppResolver} */
+export function appResolver() {
+ return {
+ name: '@sveltejs/esbuild-plugin-app-resolver',
+ setup(build) {
+ build.onResolve({ filter: /@sveltejs\/kit\/app/ }, (args) => ({
+ path: join(args.resolveDir, '../output/server/app.js')
+ }));
+ }
+ };
+}

packages/kit/src/core/adapt/prerender.js

@@ -1,11 +1,13 @@
 import { readFileSync, writeFileSync } from 'fs';
 import { dirname, join, resolve as resolve_path } from 'path';
 import { pathToFileURL, resolve, URL } from 'url';
-import { mkdirp } from '../../utils/filesystem.js';
+
 import { __fetch_polyfill } from '../../install-fetch.js';
-import { SVELTE_KIT } from '../constants.js';
+import { mkdirp } from '../../utils/filesystem.js';
 import { get_single_valued_header } from '../../utils/http.js';
 
+import { SVELTE_KIT } from '../constants.js';
+
 /**
  * @typedef {import('types/config').PrerenderErrorHandler} PrerenderErrorHandler
  * @typedef {import('types/config').PrerenderOnErrorValue} OnError