Enable caching publish directory

helpers/incremental/caching.js

@@ -1,7 +1,17 @@
-import { promises as fs } from 'fs'
+import path from 'path'
 
 import { default as TOML } from '@iarna/toml'
+// https://github.com/jprichardson/node-fs-extra
+import fs from 'fs-extra'
 
+import { isProduction, rootDir } from '../environment.js'
+
+
+
+// https://github.com/hanbyul-here/nuxt-incremental-build-exp/blob/cb3ef6b001b283de77efee64733db273d991129b/cache-me.js
+export const CACHE_PATH = isProduction
+    ? path.join('/', 'opt', 'build', 'cache', 'app_build') // Netlify cache path
+    : path.join(rootDir, '.app_build_cache')//path.resolve(__dirname, '.app_build_cache')
 
 
 export async function getNetlifyConfig () {
@@ -11,3 +21,39 @@ export async function getNetlifyConfig () {
 
     return TOML.parse( netlifyTomlContents )
 }
+
+
+export async function getPublishDirectoryName () {
+    const netlifyConfig = await getNetlifyConfig()
+
+    return netlifyConfig.build.publish
+}
+
+
+export async function getPublishDirectoryPath () {
+    const publishDirectoryPath = await getPublishDirectoryName()
+
+    return path.resolve( rootDir, publishDirectoryPath )
+}
+
+
+export async function hasCachedPublishFolder () {
+    const homePageFile = `${ CACHE_PATH }/index.html`
+
+    // https://github.com/jprichardson/node-fs-extra/blob/master/docs/pathExists.md
+    return await fs.pathExists( homePageFile )
+}
+
+
+export async function cachePublishFolder () {
+
+    const publishDirectoryPath = await getPublishDirectoryPath()
+
+    console.log('publishDirectoryPath', publishDirectoryPath)
+
+    // Make sure cache folder exists
+    await fs.ensureDir( CACHE_PATH )
+
+    await fs.copy( publishDirectoryPath, CACHE_PATH )
+
+}