Adding a script to automatically build testing versions of core packages

Summary: `node scripts/build-packages.js` will create local builds of the React VR packages (`react-vr`, `react-vr-web`, `ovrui`) and place them in `./package_builds`. Once they have been built, you can run your project against the master version of React VR by running `npm install path/to/react-vr-x.y.z.tgz`, etc from your project directory.

Reviewed By: macarran

Differential Revision: D5064084

fbshipit-source-id: c819c46

.gitignore

@@ -4,3 +4,4 @@ node_modules
 .DS_Store
 *.log
 EndToEnd/testapp/build
+package_builds

scripts/build-packages.js

@@ -0,0 +1,99 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+'use strict';
+
+const child_process = require('child_process');
+const fs = require('fs');
+const path = require('path');
+
+function prepare() {
+  return new Promise((resolve, reject) => {
+    // Build OVRUI
+    const npm = child_process.spawn('npm', ['run', 'build'], {
+      stdio: 'inherit',
+      cwd: PACKAGES.ovrui,
+    });
+    npm.on('close', code => {
+      if (code !== 0) {
+        reject(code);
+      }
+      resolve();
+    });
+  });
+}
+
+function buildPackage(name, dir) {
+  console.log(`  Packaging \x1b[32m'${name}'\x1b[0m`);
+  return new Promise((resolve, reject) => {
+    const json = path.resolve(dir, 'package.json');
+    fs.stat(json, (err, res) => {
+      if (err) {
+        console.log(`\x1b[41;1m${json} does not exist\x1b[0m`);
+        reject(err);
+        return;
+      }
+      resolve(json);
+    });
+  }).then(json => {
+    const version = require(json).version;
+    return new Promise((resolve, reject) => {
+      const npm = child_process.spawn('npm', ['pack'], {stdio: 'inherit', cwd: dir});
+      npm.on('close', code => {
+        if (code !== 0) {
+          reject(code);
+        }
+        resolve(path.resolve(dir, `${name}-${version}.tgz`));
+      });
+    });
+  });
+}
+
+function relocatePackage(name, src, dest, rev) {
+  const destfile = path.join(dest, `${name}-${rev}.tgz`);
+  console.log(`Moving ${src} to ${destfile}`);
+  return new Promise((resolve, reject) => {
+    fs.rename(src, destfile, () => {
+      resolve();
+    });
+  });
+}
+
+function ensureDirectory(dir) {
+  try {
+    const stat = fs.statSync(dir);
+    if (stat) {
+      return;
+    }
+  } catch (e) {
+    fs.mkdirSync(dir);
+  }
+}
+
+const PACKAGES = {
+  ovrui: path.resolve(__dirname, '..', 'OVRUI'),
+  'react-vr': path.resolve(__dirname, '..'),
+  'react-vr-web': path.resolve(__dirname, '..', 'ReactVR'),
+};
+
+const rev = child_process.execSync('git rev-parse HEAD').toString().trim().substr(0, 8);
+console.log(`\x1b[34;1mBuilding packages at git rev ${rev}...\x1b[0m`);
+const DEST = path.resolve(__dirname, '..', 'package_builds');
+ensureDirectory(DEST);
+prepare()
+  .then(() => {
+    return Promise.all(
+      Object.keys(PACKAGES).map(p =>
+        buildPackage(p, PACKAGES[p]).then(src => relocatePackage(p, src, DEST, rev))
+      )
+    );
+  })
+  .then(() => {
+    console.log(`\nBuilt all packages! They are located at \x1b[34m${DEST}\x1b[0m`);
+  });