Question

以下我想要实现：

将图片上传到我的后台
调整此图片大小以减小图像尺寸。
将此图片上传到Amazon AWS S3。

我无法弄清楚如何将图片直接存储到Amazon AWS S3，因此我首先将其上传到我的后台。

我的代码：

router.post('/fileupload', function(req, res){

  // Prepare data
  var file = req.files.upfile;
  var uploadpath = 'profilepicture/' + req.session.user + '.jpg';
  var AWS = require('aws-sdk');
  var fs = require('fs');
  AWS.config.update({
    accessKeyId: **,
    secretAccessKey: **
  });

  // Upload file
  file.mv(uploadpath,function(err){
    if (err) throw err;

    // Read in the file, convert it to base64, store to S3
     Jimp.read(uploadpath, function (err, data) {
       if (err) throw err;

       // Reduce size
       data.resize(400, Jimp.AUTO).quality(100).write(uploadpath);

       var s3 = new AWS.S3();
       var stream = fs.createReadStream(uploadpath);

       s3.putObject({
           Bucket: bucketAmazon,
           Key: req.session.user + '.jpg',
           ContentType: 'image/jpg',
           Body: stream,
           ContentEncoding: 'base64',
           ACL: 'public-read',
           Metadata: {
             'Content-Type': 'image/jpeg'
           }
         }, function (resp) {
           console.log(arguments);
           console.log('Successfully uploaded package.');
           return res.render('settings', {
             user: req.session.user,
             logged: true,
             wrongPicture: false
           });
       });
    });
  });
});

然而，当我运行此代码时：文件被上传到我的后台并正确裁剪，但在Amazon AWS S3中它显示大小为'0 B'。

如果我删除了行data.resize(400, Jimp.AUTO).quality(100).write(uploadpath)，那么该文件会正确上传到Amazon AWS S3，但当然图片不会缩小。

Answer 1

您可以使用write回调来保证在上传开始之前写入文件。

...
data.resize(400, Jimp.AUTO).quality(100).write(uploadpath, () => {
    // upload to s3 code here
});

在NodeJS中将Jimp-module与Amazon AWS S3相结合

1 个答案: