docs: archive v5 docs (#3482)

Author: liamdebeasi

docusaurus.config.js

@@ -4,6 +4,27 @@ const fetch = require('node-fetch');
 
 const VERSIONS_JSON = require('./versions.json');
 
+/**
+ * Old versions of the Ionic Docs are archived so
+ * that we do not need to re-build it every time we deploy.
+ * Building a large number of docs sites at once can cause
+ * out of memory issues, so archiving old docs sites
+ * allow us to keep memory usage and build times low.
+ *
+ * Note that this file is only for versions of the Ionic Docs
+ * that are built with Docusaurus. The
+ * Ionic v3 and v4 docs are built with other tools, so those
+ * versions are not included here.
+ */
+const ARCHIVED_VERSIONS_JSON = require('./versionsArchived.json');
+
+/**
+ * This returns an array where each entry is an array
+ * containing the version name at index 0 and
+ * the archive url at index 1.
+ */
+const ArchivedVersionsDropdownItems = Object.entries(ARCHIVED_VERSIONS_JSON).splice(0, 5);
+
 const BASE_URL = '/docs';
 
 module.exports = {
@@ -165,6 +186,20 @@ module.exports = {
           type: 'docsVersionDropdown',
           position: 'right',
           dropdownItemsAfter: [
+            ...ArchivedVersionsDropdownItems.map(([versionName, versionUrl]) => ({
+              label: versionName,
+              /**
+               * Use "to" instead of "href" so the
+               * external URL icon does not show up.
+               */
+              to: versionUrl,
+              /**
+               * Just like the version docs in this project,
+               * we want to archived versions to open in the
+               * same tab.
+               */
+              target: '_self',
+            })),
             { to: 'https://ionicframework.com/docs/v4/components', label: 'v4', target: '_blank' },
             { to: 'https://ionicframework.com/docs/v3/', label: 'v3', target: '_blank' },
           ],

package.json

@@ -7,7 +7,7 @@
   },
   "scripts": {
     "prebuild": "npm run generate-markdown; scripts/i18n.sh; if [ -n \"$CROWDIN_PERSONAL_TOKEN\" ]; then npm run crowdin:sync; fi",
-    "build": "NODE_OPTIONS=--max_old_space_size=8192 npm run build:${VERCEL_ENV:-preview}",
+    "build": "npm run build:${VERCEL_ENV:-preview}",
     "build:preview": "docusaurus build --locale en",
     "build:production": "docusaurus build",
     "clear": "docusaurus clear",

versions.json

@@ -1,5 +1,4 @@
 [
   "v7",
-  "v6",
-  "v5"
+  "v6"
 ]

versionsArchived.json

@@ -0,0 +1,3 @@
+{
+  "v5": "https://ionic-docs-5utg8ms4c-ionic1.vercel.app/docs/v5/"
+}