feat(v2): createData plugin API (#1400)

* feat(v2): createModule plugin api

* remove unused stuff

* address review, createModule -> createData

* link.link -> link.url

* remove youtube page

* update yarn.lock

packages/docusaurus-plugin-content-pages/src/index.js

@@ -7,11 +7,9 @@
 
 const globby = require('globby');
 const path = require('path');
-const {encodePath, fileToPath, idx} = require('@docusaurus/utils');
+const {encodePath, fileToPath, idx, docuHash} = require('@docusaurus/utils');
 
 const DEFAULT_OPTIONS = {
-  metadataKey: 'pagesMetadata',
-  metadataFileName: 'pagesMetadata.json',
   path: 'pages', // Path to data on filesystem, relative to site dir.
   routeBasePath: '', // URL Route.
   include: ['**/*.{js,jsx}'], // Extensions to include.
@@ -96,20 +94,26 @@ class DocusaurusPluginContentPages {
 
   async contentLoaded({content, actions}) {
     const {component} = this.options;
-    const {addRoute} = actions;
+    const {addRoute, createData} = actions;
 
-    content.forEach(metadataItem => {
-      const {permalink, source} = metadataItem;
-      addRoute({
-        path: permalink,
-        component,
-        exact: true,
-        metadata: metadataItem,
-        modules: {
-          content: source,
-        },
-      });
-    });
+    await Promise.all(
+      content.map(async metadataItem => {
+        const {permalink, source} = metadataItem;
+        const metadataPath = await createData(
+          `${docuHash(permalink)}.json`,
+          JSON.stringify(metadataItem, null, 2),
+        );
+        addRoute({
+          path: permalink,
+          component,
+          exact: true,
+          modules: {
+            content: source,
+            metadata: metadataPath,
+          },
+        });
+      }),
+    );
   }
 }