Appand Apache 2.0 license to all .js files found in a js folder

append-license.js

const path = require( "path" );
const fs = require( "fs" );

const license = new Buffer( `/**
 * Copyright 2016 Google Inc. All rights reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

` );

function findAllJSFiles( base ) {
    fs.readdirSync( base ).forEach( function( name ) {

        const filePath = path.join( base, name );

        if ( fs.statSync( filePath ).isDirectory() ) findAllJSFiles( filePath );
        else if ( name.endsWith( ".js" ) ) appendLicense( filePath );

    } );
}

function appendLicense( filePath ) {
    var content = fs.readFileSync( filePath );
    var fd = fs.openSync( filePath, "w+" );

    fs.appendFileSync( fd, license );
    fs.appendFileSync( fd, content );

    fs.close( fd );
}

findAllJSFiles( path.join( __dirname, "js" ) );