Revalidate Type (#56763)

This adds a new `Revalidate` type which is used internally by Next.js to associate the user inputted value of `revalidate` from `getStaticProps` or the exported `revalidate` variable in app directory.

Author: wyattjoh

packages/next/src/build/index.ts

@@ -9,6 +9,7 @@ import type {
   ExportAppWorker,
   ExportPageInput,
 } from '../export/types'
+import type { Revalidate } from '../server/lib/revalidate'
 
 import '../lib/setup-exception-listeners'
 
@@ -169,7 +170,7 @@ interface DataRouteRouteInfo {
 export interface SsgRoute
   extends ExperimentalBypassForInfo,
     DataRouteRouteInfo {
-  initialRevalidateSeconds: number | false
+  initialRevalidateSeconds: Revalidate
   srcRoute: string | null
   initialStatus?: number
   initialHeaders?: Record<string, string>

packages/next/src/export/routes/app-page.ts

@@ -107,7 +107,7 @@ export async function exportAppPage(
     const html = result.toUnchunkedString()
     const { metadata } = result
     const flightData = metadata.pageData
-    const revalidate = metadata.revalidate
+    const revalidate = metadata.revalidate ?? false
 
     if (revalidate === 0) {
       if (isDynamicError) {

packages/next/src/export/routes/pages.ts

@@ -214,7 +214,7 @@ export async function exportPages(
 
   return {
     ampValidations,
-    revalidate: metadata.revalidate,
+    revalidate: metadata.revalidate ?? false,
     ssgNotFound,
   }
 }

packages/next/src/export/types.ts

@@ -7,6 +7,7 @@ import type AmpHtmlValidator from 'next/dist/compiled/amphtml-validator'
 import type { FontConfig } from '../server/font-utils'
 import type { ExportPathMap, NextConfigComplete } from '../server/config-shared'
 import type { Span } from '../trace'
+import type { Revalidate } from '../server/lib/revalidate'
 
 export interface AmpValidation {
   page: string
@@ -62,7 +63,7 @@ export type ExportedPageFile = {
 export type ExportRouteResult =
   | {
       ampValidations?: AmpValidation[]
-      revalidate: number | false
+      revalidate: Revalidate
       metadata?: {
         status?: number
         headers?: OutgoingHttpHeaders
@@ -126,7 +127,7 @@ export type ExportAppResult = {
       /**
        * The revalidation time for the page in seconds.
        */
-      revalidate?: number | false
+      revalidate?: Revalidate
       /**
        * The metadata for the page.
        */

packages/next/src/server/lib/revalidate.ts

@@ -0,0 +1,8 @@
+/**
+ * The revalidate option used internally for pages. A value of `false` means
+ * that the page should not be revalidated. A number means that the page
+ * should be revalidated after the given number of seconds (this also includes
+ * `1` which means to revalidate after 1 second). A value of `0` is not a valid
+ * value for this option.
+ */
+export type Revalidate = number | false

packages/next/src/server/render-result.ts

@@ -1,12 +1,14 @@
 import type { StaticGenerationStore } from '../client/components/static-generation-async-storage.external'
+import type { Revalidate } from './lib/revalidate'
 import type { PipeTarget } from './pipe-readable'
+
 import { pipeReadable } from './pipe-readable'
 
 type ContentTypeOption = string | undefined
 
 export type RenderResultMetadata = {
   pageData?: any
-  revalidate?: any
+  revalidate?: Revalidate
   staticBailoutInfo?: any
   assetQueryString?: string
   isNotFound?: boolean

packages/next/src/server/render.tsx

@@ -37,6 +37,8 @@ import type { NextFontManifest } from '../build/webpack/plugins/next-font-manife
 import type { PagesModule } from './future/route-modules/pages/module'
 import type { ComponentsEnhancer } from '../shared/lib/utils'
 import type { NextParsedUrlQuery } from './request-meta'
+import type { Revalidate } from './lib/revalidate'
+
 import React from 'react'
 import ReactDOMServer from 'react-dom/server.browser'
 import { StyleRegistry, createStyleRegistry } from 'styled-jsx'
@@ -820,7 +822,7 @@ export async function renderToHTMLImpl(
   }
 
   if (isSSG && !isFallback) {
-    let data: UnwrapPromise<ReturnType<GetStaticProps>>
+    let data: Readonly<UnwrapPromise<ReturnType<GetStaticProps>>>
 
     try {
       data = await getTracer().trace(
@@ -931,6 +933,7 @@ export async function renderToHTMLImpl(
       )
     }
 
+    let revalidate: Revalidate
     if ('revalidate' in data) {
       if (data.revalidate && renderOpts.nextConfigOutput === 'export') {
         throw new Error(
@@ -951,24 +954,28 @@ export async function renderToHTMLImpl(
               `\n\nTo never revalidate, you can set revalidate to \`false\` (only ran once at build-time).` +
               `\nTo revalidate as soon as possible, you can set the value to \`1\`.`
           )
-        } else if (data.revalidate > 31536000) {
-          // if it's greater than a year for some reason error
-          console.warn(
-            `Warning: A page's revalidate option was set to more than a year for ${req.url}. This may have been done in error.` +
-              `\nTo only run getStaticProps at build-time and not revalidate at runtime, you can set \`revalidate\` to \`false\`!`
-          )
+        } else {
+          if (data.revalidate > 31536000) {
+            // if it's greater than a year for some reason error
+            console.warn(
+              `Warning: A page's revalidate option was set to more than a year for ${req.url}. This may have been done in error.` +
+                `\nTo only run getStaticProps at build-time and not revalidate at runtime, you can set \`revalidate\` to \`false\`!`
+            )
+          }
+
+          revalidate = data.revalidate
         }
       } else if (data.revalidate === true) {
         // When enabled, revalidate after 1 second. This value is optimal for
         // the most up-to-date page possible, but without a 1-to-1
         // request-refresh ratio.
-        data.revalidate = 1
+        revalidate = 1
       } else if (
         data.revalidate === false ||
         typeof data.revalidate === 'undefined'
       ) {
         // By default, we never revalidate.
-        data.revalidate = false
+        revalidate = false
       } else {
         throw new Error(
           `A page's revalidate option must be seconds expressed as a natural number. Mixed numbers and strings cannot be used. Received '${JSON.stringify(
@@ -978,7 +985,7 @@ export async function renderToHTMLImpl(
       }
     } else {
       // By default, we never revalidate.
-      ;(data as any).revalidate = false
+      revalidate = false
     }
 
     props.pageProps = Object.assign(
@@ -988,8 +995,7 @@ export async function renderToHTMLImpl(
     )
 
     // pass up revalidate and props for export
-    renderResultMeta.revalidate =
-      'revalidate' in data ? data.revalidate : undefined
+    renderResultMeta.revalidate = revalidate
     renderResultMeta.pageData = props
 
     // this must come after revalidate is added to renderResultMeta

packages/next/src/server/response-cache/types.ts

@@ -1,5 +1,6 @@
 import type { OutgoingHttpHeaders } from 'http'
 import type RenderResult from '../render-result'
+import type { Revalidate } from '../lib/revalidate'
 
 export interface ResponseCacheBase {
   get(
@@ -93,7 +94,7 @@ export type ResponseCacheValue =
   | CachedRouteValue
 
 export type ResponseCacheEntry = {
-  revalidate?: number | false
+  revalidate?: Revalidate
   value: ResponseCacheValue | null
   isStale?: boolean | -1
   isMiss?: boolean
@@ -121,6 +122,6 @@ export interface IncrementalCache {
   set: (
     key: string,
     data: IncrementalCacheValue | null,
-    ctx: { revalidate: number | false }
+    ctx: { revalidate: Revalidate }
   ) => Promise<void>
 }