diff --git a/src/index.js b/src/index.js
index fed8470..7cce780 100644
--- a/src/index.js
+++ b/src/index.js
@@ -185,6 +185,15 @@ const prerender = PCancelable.fn(
)
const payload = await getPayload(url, opts)
+ // page.content() succeeds on 4xx/5xx challenge pages; only cancel
+ // fetch when prerender is actually usable, otherwise keep a 2xx/3xx fetch.
+ if (payload.statusCode >= 400) {
+ const { isRejected, ...dataProps } = await fetchRes
+ if (!isRejected && dataProps.statusCode < 400) {
+ debug('prerender', { url, state: 'fallback', statusCode: payload.statusCode })
+ return dataProps
+ }
+ }
await fetchRes.cancel()
debug('prerender', { url, state: 'success' })
return payload
diff --git a/test/mode.js b/test/mode.js
index 24c8261..094c3de 100644
--- a/test/mode.js
+++ b/test/mode.js
@@ -1,6 +1,6 @@
'use strict'
-const { getBrowserContext, test } = require('./helpers')
+const { getBrowserContext, runServer, test } = require('./helpers')
const getHTML = require('../src')
@@ -30,6 +30,61 @@ test("`{ prerender: 'auto' }`", async t => {
t.is(stats.mode, 'fetch')
})
+test('prerender 4xx falls back to a successful fetch', async t => {
+ const url = await runServer(t, (_, res) => {
+ res.setHeader('content-type', 'text/html')
+ res.end('About Us')
+ })
+
+ const blockedBrowserless = () => ({
+ evaluate: () => async () => ({
+ headers: { 'content-type': 'text/html' },
+ html: 'ERROR: The request could not be satisfied',
+ mode: 'prerender',
+ url: String(url),
+ statusCode: 403,
+ redirects: []
+ })
+ })
+
+ const { stats, html, statusCode } = await getHTML(String(url), {
+ prerender: true,
+ getBrowserless: blockedBrowserless
+ })
+
+ t.is(stats.mode, 'fetch')
+ t.is(statusCode, 200)
+ t.true(html.includes('About Us'))
+})
+
+test('prerender 4xx is kept when fetch is also unsuccessful', async t => {
+ const url = await runServer(t, (_, res) => {
+ res.statusCode = 403
+ res.setHeader('content-type', 'text/html')
+ res.end('blocked')
+ })
+
+ const blockedBrowserless = () => ({
+ evaluate: () => async () => ({
+ headers: { 'content-type': 'text/html' },
+ html: 'ERROR: The request could not be satisfied',
+ mode: 'prerender',
+ url: String(url),
+ statusCode: 403,
+ redirects: []
+ })
+ })
+
+ const { stats, html, statusCode } = await getHTML(String(url), {
+ prerender: true,
+ getBrowserless: blockedBrowserless
+ })
+
+ t.is(stats.mode, 'prerender')
+ t.is(statusCode, 403)
+ t.true(html.includes('The request could not be satisfied'))
+})
+
test.skip('prerender error fallback into fetch mode', async t => {
const url =
'https://www.sportsnet.ca/hockey/nhl/leafs-john-tavares-return-new-york-hope-positive/'