Simplify Server Action Webpack plugin (#71721)

This PR simplifies our `flight-client-entry-plugin` to not re-compute
the server reference IDs because they're already provided in `buildInfo`
via our SWC transform. It's also a small performance win depending on
the number of Server Actions in the project.

Cherry-picked from #71463.

packages/next/src/build/analysis/get-page-static-info.ts

@@ -149,6 +149,7 @@ export function getRSCModuleInformation(
   return {
     type,
     actions,
+    actionIds: parsedActionsMeta,
     clientRefs,
     clientEntryType,
     isClientRef,

packages/next/src/build/webpack/loaders/next-flight-action-entry-loader.ts

@@ -1,20 +1,18 @@
-import { generateActionId } from './utils'
-
 export type NextFlightActionEntryLoaderOptions = {
   actions: string
-  encryptionKey: string
 }
 
 function nextFlightActionEntryLoader(this: any) {
-  const { actions, encryptionKey }: NextFlightActionEntryLoaderOptions =
-    this.getOptions()
+  const { actions }: NextFlightActionEntryLoaderOptions = this.getOptions()
 
-  const actionList = JSON.parse(actions) as [string, string[]][]
+  const actionList = JSON.parse(actions) as [
+    string,
+    [id: string, name: string][],
+  ][]
   const individualActions = actionList
-    .map(([path, names]) => {
-      return names.map((name) => {
-        const id = generateActionId(encryptionKey, path, name)
-        return [id, path, name] as [string, string, string]
+    .map(([path, actionsFromModule]) => {
+      return actionsFromModule.map(([id, name]) => {
+        return [id, path, name]
       })
     })
     .flat()

packages/next/src/build/webpack/loaders/utils.ts

@@ -1,5 +1,4 @@
 import type webpack from 'webpack'
-import { createHash } from 'crypto'
 import { RSC_MODULE_TYPES } from '../../../shared/lib/constants'
 
 const imageExtensions = ['jpg', 'jpeg', 'png', 'webp', 'avif', 'ico', 'svg']
@@ -47,25 +46,15 @@ export function isCSSMod(mod: {
 export function getActionsFromBuildInfo(mod: {
   resource: string
   buildInfo?: any
-}): undefined | string[] {
-  return mod.buildInfo?.rsc?.actions
+}): undefined | Record<string, string> {
+  return mod.buildInfo?.rsc?.actionIds
 }
 
-export function generateActionId(
-  hashSalt: string,
-  filePath: string,
-  exportName: string
-) {
-  return createHash('sha1')
-    .update(hashSalt + filePath + ':' + exportName)
-    .digest('hex')
-}
-
-export function encodeToBase64<T extends {}>(obj: T): string {
+export function encodeToBase64<T extends object>(obj: T): string {
   return Buffer.from(JSON.stringify(obj)).toString('base64')
 }
 
-export function decodeFromBase64<T extends {}>(str: string): T {
+export function decodeFromBase64<T extends object>(str: string): T {
   return JSON.parse(Buffer.from(str, 'base64').toString('utf8'))
 }
 

packages/next/src/build/webpack/plugins/flight-client-entry-plugin.ts

@@ -25,7 +25,6 @@ import {
 } from '../../../shared/lib/constants'
 import {
   getActionsFromBuildInfo,
-  generateActionId,
   isClientComponentEntryModule,
   isCSSMod,
   regexCSS,
@@ -43,6 +42,8 @@ import { getModuleBuildInfo } from '../loaders/get-module-build-info'
 import { getAssumedSourceType } from '../loaders/next-flight-loader'
 import { isAppRouteRoute } from '../../../lib/is-app-route-route'
 
+type ActionIdNamePair = [id: string, name: string]
+
 interface Options {
   dev: boolean
   appDir: string
@@ -283,14 +284,17 @@ export class FlightClientEntryPlugin {
 
     const addActionEntryList: Array<ReturnType<typeof this.injectActionEntry>> =
       []
-    const actionMapsPerEntry: Record<string, Map<string, string[]>> = {}
-    const createdActions = new Set<string>()
+    const actionMapsPerEntry: Record<
+      string,
+      Map<string, ActionIdNamePair[]>
+    > = {}
+    const createdActionIds = new Set<string>()
 
     // For each SC server compilation entry, we need to create its corresponding
     // client component entry.
     forEachEntryModule(compilation, ({ name, entryModule }) => {
       const internalClientComponentEntryImports: ClientComponentImports = {}
-      const actionEntryImports = new Map<string, string[]>()
+      const actionEntryImports = new Map<string, ActionIdNamePair[]>()
       const clientEntriesToInject = []
       const mergedCSSimports: CssImports = {}
 
@@ -310,8 +314,8 @@ export class FlightClientEntryPlugin {
             resolvedModule: connection.resolvedModule,
           })
 
-        actionImports.forEach(([dep, names]) =>
-          actionEntryImports.set(dep, names)
+        actionImports.forEach(([dep, actions]) =>
+          actionEntryImports.set(dep, actions)
         )
 
         const isAbsoluteRequest = path.isAbsolute(entryRequest)
@@ -429,7 +433,7 @@ export class FlightClientEntryPlugin {
           actions: actionEntryImports,
           entryName: name,
           bundlePath: name,
-          createdActions,
+          createdActionIds,
         })
       )
     }
@@ -458,7 +462,10 @@ export class FlightClientEntryPlugin {
     await Promise.all(addActionEntryList)
 
     const addedClientActionEntryList: Promise<any>[] = []
-    const actionMapsPerClientEntry: Record<string, Map<string, string[]>> = {}
+    const actionMapsPerClientEntry: Record<
+      string,
+      Map<string, ActionIdNamePair[]>
+    > = {}
 
     // We need to create extra action entries that are created from the
     // client layer.
@@ -484,21 +491,21 @@ export class FlightClientEntryPlugin {
       }
     }
 
-    for (const [name, actionEntryImports] of Object.entries(
+    for (const [entryName, actionEntryImports] of Object.entries(
       actionMapsPerClientEntry
     )) {
       // If an action method is already created in the server layer, we don't
       // need to create it again in the action layer.
       // This is to avoid duplicate action instances and make sure the module
       // state is shared.
       let remainingClientImportedActions = false
-      const remainingActionEntryImports = new Map<string, string[]>()
-      for (const [dep, actionNames] of actionEntryImports) {
+      const remainingActionEntryImports = new Map<string, ActionIdNamePair[]>()
+      for (const [dep, actions] of actionEntryImports) {
         const remainingActionNames = []
-        for (const actionName of actionNames) {
-          const id = name + '@' + dep + '@' + actionName
-          if (!createdActions.has(id)) {
-            remainingActionNames.push(actionName)
+        for (const action of actions) {
+          // `action` is a [id, name] pair.
+          if (!createdActionIds.has(entryName + '@' + action[0])) {
+            remainingActionNames.push(action)
           }
         }
         if (remainingActionNames.length > 0) {
@@ -513,10 +520,10 @@ export class FlightClientEntryPlugin {
             compiler,
             compilation,
             actions: remainingActionEntryImports,
-            entryName: name,
-            bundlePath: name,
+            entryName,
+            bundlePath: entryName,
             fromClient: true,
-            createdActions,
+            createdActionIds,
           })
         )
       }
@@ -533,7 +540,7 @@ export class FlightClientEntryPlugin {
     dependencies: ReturnType<typeof webpack.EntryPlugin.createDependency>[]
   }) {
     // action file path -> action names
-    const collectedActions = new Map<string, string[]>()
+    const collectedActions = new Map<string, ActionIdNamePair[]>()
 
     // Keep track of checked modules to avoid infinite loops with recursive imports.
     const visitedModule = new Set<string>()
@@ -558,7 +565,7 @@ export class FlightClientEntryPlugin {
 
         const actions = getActionsFromBuildInfo(mod)
         if (actions) {
-          collectedActions.set(modResource, actions)
+          collectedActions.set(modResource, Object.entries(actions))
         }
 
         // Collect used exported actions transversely.
@@ -617,14 +624,14 @@ export class FlightClientEntryPlugin {
   }): {
     cssImports: CssImports
     clientComponentImports: ClientComponentImports
-    actionImports: [string, string[]][]
+    actionImports: [string, ActionIdNamePair[]][]
   } {
     // Keep track of checked modules to avoid infinite loops with recursive imports.
     const visitedOfClientComponentsTraverse = new Set()
 
     // Info to collect.
     const clientComponentImports: ClientComponentImports = {}
-    const actionImports: [string, string[]][] = []
+    const actionImports: [string, ActionIdNamePair[]][] = []
     const CSSImports = new Set<string>()
 
     const filterClientComponents = (
@@ -652,7 +659,7 @@ export class FlightClientEntryPlugin {
 
       const actions = getActionsFromBuildInfo(mod)
       if (actions) {
-        actionImports.push([modResource, actions])
+        actionImports.push([modResource, Object.entries(actions)])
       }
 
       if (isCSSMod(mod)) {
@@ -839,20 +846,20 @@ export class FlightClientEntryPlugin {
     entryName,
     bundlePath,
     fromClient,
-    createdActions,
+    createdActionIds,
   }: {
     compiler: webpack.Compiler
     compilation: webpack.Compilation
-    actions: Map<string, string[]>
+    actions: Map<string, ActionIdNamePair[]>
     entryName: string
     bundlePath: string
-    createdActions: Set<string>
+    createdActionIds: Set<string>
     fromClient?: boolean
   }) {
     const actionsArray = Array.from(actions.entries())
-    for (const [dep, actionNames] of actions) {
-      for (const actionName of actionNames) {
-        createdActions.add(entryName + '@' + dep + '@' + actionName)
+    for (const [, actionsFromModule] of actions) {
+      for (const [id] of actionsFromModule) {
+        createdActionIds.add(entryName + '@' + id)
       }
     }
 
@@ -862,17 +869,15 @@ export class FlightClientEntryPlugin {
 
     const actionLoader = `next-flight-action-entry-loader?${stringify({
       actions: JSON.stringify(actionsArray),
-      encryptionKey: this.encryptionKey,
       __client_imported__: fromClient,
     })}!`
 
     const currentCompilerServerActions = this.isEdgeServer
       ? pluginState.edgeServerActions
       : pluginState.serverActions
 
-    for (const [actionFilePath, actionNames] of actionsArray) {
-      for (const name of actionNames) {
-        const id = generateActionId(this.encryptionKey, actionFilePath, name)
+    for (const [, actionsFromModule] of actionsArray) {
+      for (const [id] of actionsFromModule) {
         if (typeof currentCompilerServerActions[id] === 'undefined') {
           currentCompilerServerActions[id] = {
             workers: {},