如何在授予公共访问权限的情况下将文件上传到 AWS S3？

Question

我正在使用 aws 示例代码将文件上传到 S3，但是当它们被上传时，任何人都无法访问，即使存储桶已对所有人公开，阅读它的唯一方法是手动设置S3 控制台上的文件以提供公共访问权限。

我的服务：

@Override
public int onStartCommand(Intent intent, int flags, int startId) {
    if (intent != null && intent.getStringExtra(INTENT_KEY_NAME) != null) {
        final String key = intent.getStringExtra(INTENT_KEY_NAME);
        final File file = (File) intent.getSerializableExtra(INTENT_FILE);
        final String transferOperation = intent.getStringExtra(INTENT_TRANSFER_OPERATION);
        TransferObserver transferObserver;

        switch (transferOperation) {
            case TRANSFER_OPERATION_DOWNLOAD:
                Log.d(TAG, "Downloading " + key);
                transferObserver = transferUtility.download("aws-MYBUCKET", key, file);
                transferObserver.setTransferListener(new DownloadListener());
                break;
            case TRANSFER_OPERATION_UPLOAD:
                Log.d(TAG, "Uploading " + key);
                transferObserver = transferUtility.upload("aws-MYBUCKET", key, file);
                transferObserver.setTransferListener(new UploadListener());
                break;
        }
        return START_STICKY;
    } else return START_NOT_STICKY;

Answer 1

您应该创建一个存储桶策略。这可以授予整个存储桶或部分存储桶的公共访问权限。

来自Bucket Policy Examples - Amazon Simple Storage Service：

{
  "Version":"2012-10-17",
  "Statement":[
    {
      "Sid":"AddPerm",
      "Effect":"Allow",
      "Principal": "*",
      "Action":["s3:GetObject"],
      "Resource":["arn:aws:s3:::examplebucket/*"]
    }
  ]
}

这比授予对单个对象的访问权限更可取。