NS Vue/Rails向S3发送预签名PUT请求，给出403

Question

我的前端是Nativescript Vue应用程序。后端是Rails。我从rrails服务器获得一个预先签名的url，并使用该url在客户端发送put请求以进行图像上传。我在rails上生成了一个预先签名的url，如下所示：

def create_presigned_url
  filename = "#{self.id}.jpg"

  Aws.config[:credentials]=Aws::Credentials.new(
    "secret_id",
    "secret_key")
  s3 = Aws::S3::Resource.new(region: 'ap-southeast-1')

  bucket = 'bucket_name'
  obj = s3.bucket(bucket).object(filename)
  self.presigned_url = obj.presigned_url(:put, { acl: 'public-read' })
  self.update_column(:image_url, obj.public_url)
end

长话短说，上面的代码生成了一个预签名的url，我使用它来使用NativeScript-background-超文本传输协议插件在客户端执行放置请求：

var会话=bghttp。会话（“图像上传”）

UploadFile(session, file, url) {
    var request = {
      url: url,
      method: "PUT",
      headers: {
          "Content-Type": "application/octet-stream"
      },
      description: `Uploading ${file.substr(file.lastIndexOf("/") + 1)}` 
    };

    var task = session.uploadFile(file, request);
}

图像上传工作正常，它显示：

LOG from device Nexus 6P: 'currentBytes: 4096'
LOG from device Nexus 6P: 'totalBytes: 622121'
LOG from device Nexus 6P: 'eventName: progress'
LOG from device Nexus 6P: 'currentBytes: 323584'
LOG from device Nexus 6P: 'totalBytes: 622121'
LOG from device Nexus 6P: 'eventName: progress'
LOG from device Nexus 6P: 'currentBytes: 606208'
LOG from device Nexus 6P: 'eventName: progress'
LOG from device Nexus 6P: 'totalBytes: 622121'
LOG from device Nexus 6P: 'currentBytes: 622121'
LOG from device Nexus 6P: 'totalBytes: 622121'
LOG from device Nexus 6P: 'eventName: progress'
LOG from device Nexus 6P: 'eventName: error'
LOG from device Nexus 6P: 'eventName: 403'
LOG from device Nexus 6P: 'eventName: {}'

出现403错误，响应为：

<?xml version="1.0" encoding="UTF-8"?>
<Error>
    <Code>SignatureDoesNotMatch</Code>
    <Message>The request signature we calculated does not match the signature you provided. Check your key and signing method.</Message>
...

我在谷歌上搜索了这个错误，发现上面的所有回复都是关于有错误的AWS密钥。然而，我已经确保我在rails上有正确的AWS凭据。我怀疑这可能与生成预签名url时的内容类型有关，但我不确定。我的bucket权限似乎是正确的，但我可能错过了一些东西。我已经制定了政策和CORS。

这是桶策略：

{
    "Version": "2012-10-17",
    "Id": "my-policy-id",
    "Statement": [
        {
            "Sid": "my-sid",
            "Effect": "Allow",
            "Principal": {
                "AWS": "arn:aws:iam::my-id:user/my-user"
            },
            "Action": "s3:PutObject",
            "Resource": "arn:aws:s3:::my-bucket/*"
        }
    ]
}

这是CORS：

<?xml version="1.0" encoding="UTF-8"?>
<CORSConfiguration xmlns="http://s3.amazonaws.com/doc/2006-03-01/">
<CORSRule>
    <AllowedOrigin>*</AllowedOrigin>
    <AllowedMethod>POST</AllowedMethod>
    <AllowedMethod>PUT</AllowedMethod>
    <AllowedMethod>GET</AllowedMethod>
    <AllowedMethod>DELETE</AllowedMethod>
    <AllowedMethod>HEAD</AllowedMethod>
    <ExposeHeader>ETag</ExposeHeader>
    <AllowedHeader>*</AllowedHeader>
</CORSRule>
</CORSConfiguration>

我的IAM用户也有必要的策略。

如有任何见解，将不胜感激。

编辑：我甚至删除了bucket策略并授予所有公众对bucket的访问权限，但我仍然看到403错误。错误是签名错误。

Answer 1

我必须改变self.presigned_url=obj.presigned_url（： put，{acl：'Public-read'}）到self.presigned_url=obj.presigned_url（： put，expires_in： 10*60，content_type：'Application/octet-stream'）

而bucket ACL则为大家公开列表，私有写入。桶策略

{
    "Version": "2012-10-17",
    "Id": "policy_id",
    "Statement": [
        {
            "Sid": "my_statement_id",
            "Effect": "Allow",
            "Principal": {
                "AWS": "arn:aws:iam::user_id:user/iam_user"
            },
            "Action": "s3:PutObject",
            "Resource": "arn:aws:s3:::my_bucket/*"
        },
        {
            "Sid": "PublicRead",
            "Effect": "Allow",
            "Principal": "*",
            "Action": [
                "s3:GetObject",
                "s3:GetObjectVersion"
            ],
            "Resource": "arn:aws:s3:::my_bucket/*"
        }
    ]
}