-
-
Notifications
You must be signed in to change notification settings - Fork 1.9k
/
prerender.js
478 lines (391 loc) · 13.8 KB
/
prerender.js
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
import { existsSync, readFileSync, statSync, writeFileSync } from 'node:fs';
import { dirname, join } from 'node:path';
import { pathToFileURL } from 'node:url';
import { installPolyfills } from '../../exports/node/polyfills.js';
import { mkdirp, posixify, walk } from '../../utils/filesystem.js';
import { should_polyfill } from '../../utils/platform.js';
import { decode_uri, is_root_relative, resolve } from '../../utils/url.js';
import { escape_html_attr } from '../../utils/escape.js';
import { logger } from '../utils.js';
import { load_config } from '../config/index.js';
import { get_route_segments } from '../../utils/routing.js';
import { queue } from './queue.js';
import { crawl } from './crawl.js';
import { forked } from '../../utils/fork.js';
export default forked(import.meta.url, prerender);
/**
* @param {{
* out: string;
* manifest_path: string;
* metadata: import('types').ServerMetadata;
* verbose: boolean;
* env: Record<string, string>
* }} opts
*/
async function prerender({ out, manifest_path, metadata, verbose, env }) {
/** @type {import('types').SSRManifest} */
const manifest = (await import(pathToFileURL(manifest_path).href)).manifest;
/** @type {import('types').ServerInternalModule} */
const internal = await import(pathToFileURL(`${out}/server/internal.js`).href);
/** @type {import('types').ServerModule} */
const { Server } = await import(pathToFileURL(`${out}/server/index.js`).href);
// configure `import { building } from '$app/environment'` —
// essential we do this before analysing the code
internal.set_building(true);
/**
* @template {{message: string}} T
* @template {Omit<T, 'message'>} K
* @param {import('types').Logger} log
* @param {'fail' | 'warn' | 'ignore' | ((details: T) => void)} input
* @param {(details: K) => string} format
* @returns {(details: K) => void}
*/
function normalise_error_handler(log, input, format) {
switch (input) {
case 'fail':
return (details) => {
throw new Error(format(details));
};
case 'warn':
return (details) => {
log.error(format(details));
};
case 'ignore':
return () => {};
default:
// @ts-expect-error TS thinks T might be of a different kind, but it's not
return (details) => input({ ...details, message: format(details) });
}
}
const OK = 2;
const REDIRECT = 3;
/** @type {import('types').Prerendered} */
const prerendered = {
pages: new Map(),
assets: new Map(),
redirects: new Map(),
paths: []
};
/** @type {import('types').PrerenderMap} */
const prerender_map = new Map();
for (const [id, { prerender }] of metadata.routes) {
if (prerender !== undefined) {
prerender_map.set(id, prerender);
}
}
/** @type {Set<string>} */
const prerendered_routes = new Set();
/** @type {import('types').ValidatedKitConfig} */
const config = (await load_config()).kit;
/** @type {import('types').Logger} */
const log = logger({ verbose });
if (should_polyfill) {
installPolyfills();
}
/** @type {Map<string, string>} */
const saved = new Map();
const server = new Server(manifest);
await server.init({ env });
const handle_http_error = normalise_error_handler(
log,
config.prerender.handleHttpError,
({ status, path, referrer, referenceType }) => {
const message =
status === 404 && !path.startsWith(config.paths.base)
? `${path} does not begin with \`base\`, which is configured in \`paths.base\` and can be imported from \`$app/paths\` - see https://kit.svelte.dev/docs/configuration#paths for more info`
: path;
return `${status} ${message}${referrer ? ` (${referenceType} from ${referrer})` : ''}`;
}
);
const handle_missing_id = normalise_error_handler(
log,
config.prerender.handleMissingId,
({ path, id, referrers }) => {
return (
`The following pages contain links to ${path}#${id}, but no element with id="${id}" exists on ${path} - see the \`handleMissingId\` option in https://kit.svelte.dev/docs/configuration#prerender for more info:` +
referrers.map((l) => `\n - ${l}`).join('')
);
}
);
const handle_entry_generator_mismatch = normalise_error_handler(
log,
config.prerender.handleEntryGeneratorMismatch,
({ generatedFromId, entry, matchedId }) => {
return `The entries export from ${generatedFromId} generated entry ${entry}, which was matched by ${matchedId} - see the \`handleEntryGeneratorMismatch\` option in https://kit.svelte.dev/docs/configuration#prerender for more info.`;
}
);
const q = queue(config.prerender.concurrency);
/**
* @param {string} path
* @param {boolean} is_html
*/
function output_filename(path, is_html) {
const file = path.slice(config.paths.base.length + 1) || 'index.html';
if (is_html && !file.endsWith('.html')) {
return file + (file.endsWith('/') ? 'index.html' : '.html');
}
return file;
}
const files = new Set(walk(`${out}/client`).map(posixify));
const immutable = `${config.appDir}/immutable`;
if (existsSync(`${out}/server/${immutable}`)) {
for (const file of walk(`${out}/server/${immutable}`)) {
files.add(posixify(`${config.appDir}/immutable/${file}`));
}
}
const seen = new Set();
const written = new Set();
/** @type {Map<string, Set<string>>} */
const expected_hashlinks = new Map();
/** @type {Map<string, string[]>} */
const actual_hashlinks = new Map();
/**
* @param {string | null} referrer
* @param {string} decoded
* @param {string} [encoded]
* @param {string} [generated_from_id]
*/
function enqueue(referrer, decoded, encoded, generated_from_id) {
if (seen.has(decoded)) return;
seen.add(decoded);
const file = decoded.slice(config.paths.base.length + 1);
if (files.has(file)) return;
return q.add(() => visit(decoded, encoded || encodeURI(decoded), referrer, generated_from_id));
}
/**
* @param {string} decoded
* @param {string} encoded
* @param {string?} referrer
* @param {string} [generated_from_id]
*/
async function visit(decoded, encoded, referrer, generated_from_id) {
if (!decoded.startsWith(config.paths.base)) {
handle_http_error({ status: 404, path: decoded, referrer, referenceType: 'linked' });
return;
}
/** @type {Map<string, import('types').PrerenderDependency>} */
const dependencies = new Map();
const response = await server.respond(new Request(config.prerender.origin + encoded), {
getClientAddress() {
throw new Error('Cannot read clientAddress during prerendering');
},
prerendering: {
dependencies
},
read: (file) => {
// stuff we just wrote
const filepath = saved.get(file);
if (filepath) return readFileSync(filepath);
// stuff in `static`
return readFileSync(join(config.files.assets, file));
}
});
const encoded_id = response.headers.get('x-sveltekit-routeid');
const decoded_id = encoded_id && decode_uri(encoded_id);
if (
decoded_id !== null &&
generated_from_id !== undefined &&
decoded_id !== generated_from_id
) {
handle_entry_generator_mismatch({
generatedFromId: generated_from_id,
entry: decoded,
matchedId: decoded_id
});
}
const body = Buffer.from(await response.arrayBuffer());
save('pages', response, body, decoded, encoded, referrer, 'linked');
for (const [dependency_path, result] of dependencies) {
// this seems circuitous, but using new URL allows us to not care
// whether dependency_path is encoded or not
const encoded_dependency_path = new URL(dependency_path, 'http://localhost').pathname;
const decoded_dependency_path = decode_uri(encoded_dependency_path);
const headers = Object.fromEntries(result.response.headers);
const prerender = headers['x-sveltekit-prerender'];
if (prerender) {
const encoded_route_id = headers['x-sveltekit-routeid'];
if (encoded_route_id != null) {
const route_id = decode_uri(encoded_route_id);
const existing_value = prerender_map.get(route_id);
if (existing_value !== 'auto') {
prerender_map.set(route_id, prerender === 'true' ? true : 'auto');
}
}
}
const body = result.body ?? new Uint8Array(await result.response.arrayBuffer());
save(
'dependencies',
result.response,
body,
decoded_dependency_path,
encoded_dependency_path,
decoded,
'fetched'
);
}
// avoid triggering `filterSerializeResponseHeaders` guard
const headers = Object.fromEntries(response.headers);
if (config.prerender.crawl && headers['content-type'] === 'text/html') {
const { ids, hrefs } = crawl(body.toString(), decoded);
actual_hashlinks.set(decoded, ids);
for (const href of hrefs) {
if (!is_root_relative(href)) continue;
const { pathname, search, hash } = new URL(href, 'http://localhost');
if (search) {
// TODO warn that query strings have no effect on statically-exported pages
}
if (hash) {
const key = decode_uri(pathname + hash);
if (!expected_hashlinks.has(key)) {
expected_hashlinks.set(key, new Set());
}
/** @type {Set<string>} */ (expected_hashlinks.get(key)).add(decoded);
}
enqueue(decoded, decode_uri(pathname), pathname);
}
}
}
/**
* @param {'pages' | 'dependencies'} category
* @param {Response} response
* @param {string | Uint8Array} body
* @param {string} decoded
* @param {string} encoded
* @param {string | null} referrer
* @param {'linked' | 'fetched'} referenceType
*/
function save(category, response, body, decoded, encoded, referrer, referenceType) {
const response_type = Math.floor(response.status / 100);
const headers = Object.fromEntries(response.headers);
const type = headers['content-type'];
const is_html = response_type === REDIRECT || type === 'text/html';
const file = output_filename(decoded, is_html);
const dest = `${config.outDir}/output/prerendered/${category}/${file}`;
if (written.has(file)) return;
const encoded_route_id = response.headers.get('x-sveltekit-routeid');
const route_id = encoded_route_id != null ? decode_uri(encoded_route_id) : null;
if (route_id !== null) prerendered_routes.add(route_id);
if (response_type === REDIRECT) {
const location = headers['location'];
if (location) {
const resolved = resolve(encoded, location);
if (is_root_relative(resolved)) {
enqueue(decoded, decode_uri(resolved), resolved);
}
if (!headers['x-sveltekit-normalize']) {
mkdirp(dirname(dest));
log.warn(`${response.status} ${decoded} -> ${location}`);
writeFileSync(
dest,
`<meta http-equiv="refresh" content=${escape_html_attr(`0;url=${location}`)}>`
);
written.add(file);
if (!prerendered.redirects.has(decoded)) {
prerendered.redirects.set(decoded, {
status: response.status,
location: resolved
});
prerendered.paths.push(decoded);
}
}
} else {
log.warn(`location header missing on redirect received from ${decoded}`);
}
return;
}
if (response.status === 200) {
if (existsSync(dest) && statSync(dest).isDirectory()) {
throw new Error(
`Cannot save ${decoded} as it is already a directory. See https://kit.svelte.dev/docs/page-options#prerender-route-conflicts for more information`
);
}
const dir = dirname(dest);
if (existsSync(dir) && !statSync(dir).isDirectory()) {
const parent = decoded.split('/').slice(0, -1).join('/');
throw new Error(
`Cannot save ${decoded} as ${parent} is already a file. See https://kit.svelte.dev/docs/page-options#prerender-route-conflicts for more information`
);
}
mkdirp(dir);
log.info(`${response.status} ${decoded}`);
writeFileSync(dest, body);
written.add(file);
if (is_html) {
prerendered.pages.set(decoded, {
file
});
} else {
prerendered.assets.set(decoded, {
type
});
}
prerendered.paths.push(decoded);
} else if (response_type !== OK) {
handle_http_error({ status: response.status, path: decoded, referrer, referenceType });
}
manifest.assets.add(file);
saved.set(file, dest);
}
/** @type {Array<{ id: string, entries: Array<string>}>} */
const route_level_entries = [];
for (const [id, { entries }] of metadata.routes.entries()) {
if (entries) {
route_level_entries.push({ id, entries });
}
}
if (
config.prerender.entries.length > 1 ||
config.prerender.entries[0] !== '*' ||
route_level_entries.length > 0 ||
prerender_map.size > 0
) {
// Only log if we're actually going to do something to not confuse users
log.info('Prerendering');
}
for (const entry of config.prerender.entries) {
if (entry === '*') {
for (const [id, prerender] of prerender_map) {
if (prerender) {
if (id.includes('[')) continue;
const path = `/${get_route_segments(id).join('/')}`;
enqueue(null, config.paths.base + path);
}
}
} else {
enqueue(null, config.paths.base + entry);
}
}
for (const { id, entries } of route_level_entries) {
for (const entry of entries) {
enqueue(null, config.paths.base + entry, undefined, id);
}
}
await q.done();
// handle invalid fragment links
for (const [key, referrers] of expected_hashlinks) {
const index = key.indexOf('#');
const path = key.slice(0, index);
const id = key.slice(index + 1);
const hashlinks = actual_hashlinks.get(path);
// ignore fragment links to pages that were not prerendered
if (!hashlinks) continue;
if (!hashlinks.includes(id)) {
handle_missing_id({ id, path, referrers: Array.from(referrers) });
}
}
/** @type {string[]} */
const not_prerendered = [];
for (const [route_id, prerender] of prerender_map) {
if (prerender === true && !prerendered_routes.has(route_id)) {
not_prerendered.push(route_id);
}
}
if (not_prerendered.length > 0) {
throw new Error(
`The following routes were marked as prerenderable, but were not prerendered because they were not found while crawling your app:\n${not_prerendered.map(
(id) => ` - ${id}`
)}\n\nSee https://kit.svelte.dev/docs/page-options#prerender-troubleshooting for info on how to solve this`
);
}
return { prerendered, prerender_map };
}