Reduce versions to build on Netlify (#757)

* Reduce versions to build on Netlify

* Remove imagebackground and safeareaview from 0.5

* Keep 0.46 and 0.50

netlify.toml

@@ -1,4 +1,4 @@
 [build]
   base    = "website"
   publish = "website/build/react-native"
-  command = "sed -i -e \"s|const baseUrl .*|const baseUrl = '/';|g\" siteConfig.js && yarn install && yarn build"
+  command = "sed -i -e \"s|const baseUrl .*|const baseUrl = '/';|g\" siteConfig.js && yarn install && node netlify-reduce-versions && yarn build"

website/netlify-reduce-versions.js

@@ -0,0 +1,48 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+/**
+ * During the build process, we build a complete website for each version
+ * which is 9.2 MB / version.
+ *
+ * On Netlify, our deploy preview infrastructure, we have to upload every
+ * changed file. Each time we cut a new version or making multiple changes
+ * we're facing timeout errors from Netlify trying to upload megabytes of HTML
+ * file.
+ *
+ * This script makes sure we're not deploying unnecessary versions on Netlify.
+ *
+ * We only need 0.5 which is the first draft of each doc, and the recent ones.
+ */
+
+const fs = require('fs-extra');
+const versions = require('./versions.json');
+
+const filterWantedVersions = version =>
+  +version === 0.5 ||
+  ((version.length > 3 && +version >= 0.56) ||
+    +version === 0.46 ||
+    version === '0.50');
+
+fs.writeFileSync(
+  './versions.json',
+  JSON.stringify(versions.filter(filterWantedVersions))
+);
+
+fs.readdirSync('./versioned_docs').map(directory => {
+  if (!filterWantedVersions(directory.replace('version-', ''))) {
+    fs.removeSync(`./versioned_docs/${directory}`);
+  }
+});
+
+fs.readdirSync('./versioned_sidebars').map(directory => {
+  const match = /version-(\d.\d\d?)-sidebars.json/g.exec(directory);
+
+  if (match && !filterWantedVersions(match[1])) {
+    fs.removeSync(`./versioned_sidebars/${directory}`);
+  }
+});