TypeError:不是缓冲区node.js crypto,aws-sdk

时间:2014-06-10 15:53:15

标签: node.js amazon-web-services amazon-s3

我正在尝试为上传到amazon s3创建一个S3策略...但是在编码策略时,我得到一个类型错误:不是缓冲区。我使用的是加密版:0.0.3和aws-sdk版本:2.0.0-rc.19

这之前有用,所以我认为它可能与更新aws-sdk有关......

这是代码。评论将显示错误发生的位置:

createS3Policy = function(contentType, callback) {
    var date = new Date();
    var s3Policy = {
        'expiration': getExpiryTime(),
        'conditions': [
            ['starts-with', '$key', 'shimmy-assets/'],
            {'bucket': S3_BUCKET},
            {'acl': 'public-read'},
            ['starts-with', '$Content-Type', contentType],
            {'success_action_status' : '201'}
        ]
    };

    // stringify and encode the policy
    var stringPolicy = JSON.stringify(s3Policy);
    console.log('string policy: ' + stringPolicy);
    var base64Policy = new Buffer(stringPolicy, 'utf-8').toString('base64');

    // sign the base64 encoded policy
    // NOT A BUFFER ERROR HERE
    var signature = crypto.createHmac('sha1', AWS_SECRET_KEY).update(new Buffer(base64Policy, 'utf-8')).digest('base64');          

    // build the results object
    var s3Credentials = {
        s3Policy: base64Policy,
        s3Signature: signature,
        AWSAccessKeyId: AWS_ACCESS_KEY
    };

    // send it back
    callback(s3Credentials);
};

1 个答案:

答案 0 :(得分:2)

刚刚遇到同样的问题,所以这是我的工作代码:

我使用以下函数计算hmac;

function hmac(algorithm, key, text, encoding) {
    var hmac = crypto.createHmac(algorithm, key);

    hmac.setEncoding(encoding);
    hmac.write(text);
    hmac.end();

    return hmac.read();
};

所以我的签名是:

var signature = hmac(
    'sha1',
    secretAccessKey, //Line A
    new Buffer(JSON.stringify(policy)).toString('base64')), //Line B
    'base64');

确保未定义A行和B行。即使secretAccessKey是一个字符串,它也会抛出NOT A BUFFER错误,以防它未定义!