fix: provide payload fallback json by danielroe · Pull Request #1186 · npmx-dev/npmx.dev

danielroe · 2026-02-08T00:34:42Z

No description provided.

vercel · 2026-02-08T00:34:48Z

The latest updates on your projects. Learn more about Vercel for GitHub.

Project	Deployment	Actions	Updated (UTC)
npmx.dev	Ready	Preview, Comment	Feb 10, 2026 1:08am

2 Skipped Deployments

Project	Deployment	Actions	Updated (UTC)
docs.npmx.dev	Ignored	Preview	Feb 10, 2026 1:08am
npmx-lunaria	Ignored		Feb 10, 2026 1:08am

codecov · 2026-02-08T00:37:20Z

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ All tests successful. No failed tests found.

📢 Thoughts on this report? Let us know!

coderabbitai · 2026-02-08T00:39:02Z

Caution

Review failed

The pull request is closed.

📝 Walkthrough

Walkthrough

This pull request adds JSON fallback support to ISR. modules/isr-fallback.ts defines htmlFallback = 'spa.prerender-fallback.html' and jsonFallback = 'payload-fallback.json', writes the existing HTML fallback and a supplementary {} JSON fallback file per path, and uses the htmlFallback constant when computing output paths. nuxt.config.ts changes getISRConfig from (expirationSeconds, fallback = false) to (expirationSeconds, options: ISRConfigOptions = {}), introduces ISRConfigOptions { fallback?: 'html' | 'json' }, and updates per-route ISR entries to request either html or json fallbacks (adding _payload.json routes and JSON content-type headers when selected).

Possibly related PRs

fix: provide payload fallback json #1186: Implements the same code-level changes—adding a JSON payload fallback in modules/isr-fallback.ts and updating getISRConfig (signature, ISRConfigOptions, and per-route fallback handling) in nuxt.config.ts.
perf: use spa fallback on cold cache #878: Earlier change to the ISR fallback module and getISRConfig helper that this PR extends by adding the JSON payload fallback and new options.fallback = 'json'.

🚥 Pre-merge checks | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Description check	⚠️ Warning	The pull request lacks a description entirely, making it impossible to assess whether the author's intent aligns with the changeset.	Add a pull request description explaining the purpose of introducing payload fallback JSON handling, the problem being solved, and how the ISR configuration changes affect route handling.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing touches

📝 Generate docstrings

🧪 Generate unit tests (beta)

Create PR with unit tests
Post copyable unit tests in a comment
Commit unit tests in branch fix/payload-fallback

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

coderabbitai

Actionable comments posted: 1

coderabbitai · 2026-02-08T00:39:05Z

+interface ISRConfigOptions {
+ fallback?: 'html' | 'json'
+}
+function getISRConfig(expirationSeconds: number, options: ISRConfigOptions = {}) {
+ if (options.fallback) {
 return {
 expiration: expirationSeconds,
- fallback: 'spa.prerender-fallback.html',
+ fallback:
+ options.fallback === 'html' ? 'spa.prerender-fallback.html' : 'payload-fallback.json',
 } as { expiration: number }


⚠️ Potential issue | 🟡 Minor
🧩 Analysis chain
🏁 Script executed:
# First, find the nuxt.config.ts file find . -name "nuxt.config.ts" -type f
Repository: npmx-dev/npmx.dev
Length of output: 99
🏁 Script executed:
# Check the file size first wc -l ./nuxt.config.ts # Then read lines 280-305 to get full context sed -n '280,305p' ./nuxt.config.ts
Repository: npmx-dev/npmx.dev
Length of output: 604
🏁 Script executed:
# Check if getISRConfig is called elsewhere rg "getISRConfig" ./nuxt.config.ts # Also check for any imports or exports rg "getISRConfig". --type ts --type tsx
Repository: npmx-dev/npmx.dev
Length of output: 927
🏁 Script executed:
# Check the TypeScript strict settings to confirm strict type-safety is enforced cat ./tsconfig.json | grep -A 20 '"strict"'
Repository: npmx-dev/npmx.dev
Length of output: 43
🏁 Script executed:
# Check if tsconfig.json exists ls -la tsconfig.json 2>&1||echo"File not found"# Try reading the file cat tsconfig.json 2>&1| head -50
Repository: npmx-dev/npmx.dev
Length of output: 442
Remove the type assertion to restore type safety.
The as { expiration: number } cast on line 296 hides the fallback field from the return type, even though the function includes it in the returned object when options.fallback is provided. This violates strict type-safety requirements. Define an explicit return type that includes an optional fallback property and remove the assertion.
🔧 Proposed fix
interface ISRConfigOptions { fallback?: 'html' | 'json' } +interface ISRConfig {+ expiration: number+ fallback?: 'spa.prerender-fallback.html' | 'payload-fallback.json'+}-function getISRConfig(expirationSeconds: number, options: ISRConfigOptions = {}) {+function getISRConfig(expirationSeconds: number, options: ISRConfigOptions = {}): ISRConfig { if (options.fallback) { return { expiration: expirationSeconds, fallback: options.fallback === 'html' ? 'spa.prerender-fallback.html' : 'payload-fallback.json', - } as { expiration: number }+ } } return { expiration: expirationSeconds, } }
📝 Committable suggestion
‼️IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.
Suggested change
interfaceISRConfigOptions{
fallback?: 'html'|'json'
}
functiongetISRConfig(expirationSeconds: number,options: ISRConfigOptions={}){
if(options.fallback){
return{
expiration: expirationSeconds,
fallback: 'spa.prerender-fallback.html',
fallback:
options.fallback==='html' ? 'spa.prerender-fallback.html' : 'payload-fallback.json',
}as{expiration: number}
interfaceISRConfigOptions{
fallback?: 'html'|'json'
}
interfaceISRConfig{
expiration: number
fallback?: 'spa.prerender-fallback.html'|'payload-fallback.json'
}
functiongetISRConfig(expirationSeconds: number,options: ISRConfigOptions={}): ISRConfig{
if(options.fallback){
return{
expiration: expirationSeconds,
fallback:
options.fallback==='html' ? 'spa.prerender-fallback.html' : 'payload-fallback.json',
}
}
return{
expiration: expirationSeconds,
}
}

serhalp · 2026-02-08T00:44:10Z

For my own nuxt edification, would you mind explaining what this does and what this PR is solving for? 🙏🏼

vercel · 2026-02-10T01:01:56Z

Deployment failed with the following error:

Header at index 0 has invalid `source` regular expression "**/*_payload.json".

Learn More: https://vercel.link/invalid-route-source-pattern

danielroe · 2026-02-10T01:11:56Z

@serhalp this provides fallback json files to speed up initial fetching of payloads when the cache is cold.

it's not a nuxt thing in particular, and we do need to solve by speeding up the rendering of payloads for package pages, instead.

fix: provide payload fallback json
6f719c3

vercelBotdeployed to Preview – npmx.dev February 8, 2026 00:35 View deployment

coderabbitaiBot reviewed Feb 8, 2026
View reviewed changes

chore: set json content-type headers
92abf69

vercelBotdeployed to Preview – npmx.dev February 8, 2026 00:46 View deployment

danielroe marked this pull request as draft February 8, 2026 00:52

danielroe added 3 commits February 8, 2026 20:45

Merge remote-tracking branch 'origin/main' into fix/payload-fallback
69b15bb

Merge remote-tracking branch 'origin/main' into fix/payload-fallback
e42403c

fix: ensure payload fallbacks have json headers
8234492

fix: try different pattern
488b305

vercelBotdeployed to Preview – npmx.dev February 10, 2026 01:04 View deployment

chore: pass initialHeaders
0edfeb4

vercelBotdeployed to Preview – npmx.dev February 10, 2026 01:08 View deployment

danielroe marked this pull request as ready for review February 10, 2026 01:10

danielroe merged commit 3ea47eb into mainFeb 10, 2026
20 checks passed

danielroe deleted the fix/payload-fallback branch February 10, 2026 01:10

NandkishorJadoun mentioned this pull request Feb 10, 2026
package page doesn't load with javascript disabled #1291
Closed

This was referenced Feb 23, 2026
fix: update isr configuration for package pages #1604
Merged
perf: cache rendered payloads #1643
Merged

Navigation Menu

Uh oh!

Uh oh!

fix: provide payload fallback json - #1186

fix: provide payload fallback json#1186
danielroe merged 7 commits into
mainfrom
fix/payload-fallback

danielroe commented Feb 8, 2026

Uh oh!

vercelBot commented Feb 8, 2026•
edited
Loading

Uh oh!

codecovBot commented Feb 8, 2026

Uh oh!

coderabbitaiBot commented Feb 8, 2026•
edited
Loading

Review failed

Walkthrough

Possibly related PRs

Uh oh!

coderabbitaiBot left a comment

Uh oh!

coderabbitaiBotFeb 8, 2026

Uh oh!

serhalp commented Feb 8, 2026

Uh oh!

vercelBot commented Feb 10, 2026

Uh oh!

Uh oh!

danielroe commented Feb 10, 2026

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

2 participants

-interfaceISRConfigOptions{
- fallback?: 'html'|'json'
-}
-functiongetISRConfig(expirationSeconds: number,options: ISRConfigOptions={}){
-if(options.fallback){
-return{
-expiration: expirationSeconds,
-fallback: 'spa.prerender-fallback.html',
- fallback:
-options.fallback==='html' ? 'spa.prerender-fallback.html' : 'payload-fallback.json',
-}as{expiration: number}
+interfaceISRConfigOptions{
+ fallback?: 'html'|'json'
+}
+interfaceISRConfig{
+ expiration: number
+ fallback?: 'spa.prerender-fallback.html'|'payload-fallback.json'
+}
+functiongetISRConfig(expirationSeconds: number,options: ISRConfigOptions={}): ISRConfig{
+if(options.fallback){
+return{
+expiration: expirationSeconds,
+ fallback:
+options.fallback==='html' ? 'spa.prerender-fallback.html' : 'payload-fallback.json',
+}
+}
+return{
+expiration: expirationSeconds,
+}
+}

Uh oh!

Uh oh!

Conversation

danielroe commented Feb 8, 2026

Uh oh!

vercelBot commented Feb 8, 2026• edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

codecovBot commented Feb 8, 2026

Codecov Report

Uh oh!

coderabbitaiBot commented Feb 8, 2026• edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Review failed

Walkthrough

Possibly related PRs

Uh oh!

coderabbitaiBot left a comment

Choose a reason for hiding this comment

Uh oh!

coderabbitaiBotFeb 8, 2026

Choose a reason for hiding this comment

Uh oh!

serhalp commented Feb 8, 2026

Uh oh!

vercelBot commented Feb 10, 2026

Uh oh!

Uh oh!

danielroe commented Feb 10, 2026

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

2 participants

vercelBot commented Feb 8, 2026•
edited
Loading

coderabbitaiBot commented Feb 8, 2026•
edited
Loading