NodeJS：从AWS S3存储桶获取映像作为响应

Question

我的客户在S3上存储了大量图片。我们需要将这些图像作为响应返回。这是我写的代码：

var AWS = require('aws-sdk');
    AWS.config.update({
        accessKeyId: "AccessKey",
        secretAccessKey: "SecretAccessKey"
    });
    var s3 = new AWS.S3();
    s3.getObject({ Bucket: "BucketName", Key: "ImageURL" },
        function(error, data) {
            if (error != null) {
                var _length = data.Body.length;
                //Execution freezes here. Don't get any response.
                res.writeHead(200, {
                    'Content-Type': 'image/jpeg',
                    'Content-Length': _length
                });
                res.end(new Buffer(data.Body, 'binary'));
                } 
        }
    );

我们如何才能得到回应的图像？

Answer 1

var AWS = require('aws-sdk');
AWS.config.update({
    accessKeyId: "AccessKey",
    secretAccessKey: "SecretAccessKey"
});
var s3 = new AWS.S3();
s3.getObject({ Bucket: "BucketName", Key: "ETag.jpeg" },
    function(error, data) {
        if (error != null) {
            alert("Failed to retrieve an object: " + error);
        } else {
            alert("Loaded " + data.ContentLength + " bytes");                    
        }
    }
);