Gulp / nodejs从AWS S3下载zip文件已损坏：使用aws-sdk

Question

我尝试使用aws-sdk从AWS S3下载zip文件。我的代码下载文件，但它已损坏。我无法用7zip程序和zip命令解压缩它。也许有一些我错过的编码。

这是我的代码：

require('dotenv').config();
const AWS = require('aws-sdk');
const fs = require('fs');
const commandLineArgs   = require('command-line-args');
const options = commandLineArgs([
    {name: 'filename', alias: 'f', type: String},
]);

gulp.task('zipFromS3', function() {
    var AWS = require('aws-sdk');
    var fs = require('fs');
    AWS.config.update({accessKeyId: process.env.AWS_ACCESS_ID,secretAccessKey: process.env.AWS_ACCESS_SECRET});

    var s3bucket = new AWS.S3({params:{Bucket: env.aws.access_backups.bucket}});
    return new Promise(function(resolve,reject){
        if(options.filename == null || typeof options.filename == 'undefined'){
            return reject();
        }
        let filename = options.filename; //'2017-04-06.zip'
        var file = fs.createWriteStream(env.server.downloads + '/'+filename);
        var params = {
            Key: filename,
            Bucket: env.aws.access_backups.bucket
        };

        s3bucket.getObject(params, function(err, data){
            if (err) {reject();}
        }).createReadStream()
         .on('error', function(err){
            console.log(err);
            reject();
        })
        .on('end', function (chunk){
             resolve();
        }).pipe(file);
    });
});

我使用此脚本从s3下载一些.txt文件，这很有效。如果我去我的桶并直接从aws网站下载我的zip文件，它也可以正常工作。

压缩文件也是gulp创建的。这是创建zip文件的代码（在发送到AWS之前，此zip文件可以正确解压缩。）

const zip = require('gulp-zip');
const env = readConfig('.env.json', { override: true });
gulp.task('zip', () => {
    let now = new Date();
    let m   = now.getMonth();
    let d   = now.getDate();
    m++;
    if(m < 10){m = "0"+m;}
    if(d < 10){d = "0"+d;}

    let name = now.getFullYear()+'-'+m+'-'+d;
    if(typeof options.filename != 'undefined' && options.filename != null){
        name += "_"+options.filename;
    }

    return gulp.src(env.server.dist+"/**")
        .pipe(zip(name + ".zip"))
        .pipe(gulp.dest(env.server.zipfolder));
});