minio 分块上传
s3协议中是有定义分块上传的接口,minio支持s3协议,所以minio是支持分块上传文件的,只是没有前端直传方案,各种java client有支持分段上传,但是这个分段的方法是私有的意思就是对用户是隐藏的 当文件大小超过5mb是就会自动选择分块上传
minio没有提供前端直传方案,所以也没有提供像七牛云一样的游览器端的sdk,官网提供的javascript代码是nodejs端使用的,也就是说你的文件需要经过应用转发一遍再由应用转存到minio中而不能直接像七牛云一样使用一次性token直接在前端分块上传文件
如果需要前端直传minio需要自己开发一个网关代理minio的分块上传接口并实现类似七牛云的一次性token鉴权功能
分块实现思路
前端分块
可以使用现成的支持s3的框架,或者自己手写
Uppy 框架
https://uppy.io/
后端分块上传接口
- 分块上传接口
- 合并文件接口
分块上传涉及到哪些接口参考s3 uploadPart https://docs.aws.amazon.com/AmazonS3/latest/API/API_UploadPart.html
上传逻辑
- 调用创建批量上传接口,获取id用来后续合并文件
- 前端调用minio分块上传接口
- 前端判断是否上传完毕,上传完毕前端调用合并文件接口
接口鉴权
大多数前端上传文件都是不需要登录的,这时就需要一个好的鉴权方案,防止接口被滥用,阿里oss等厂商使用的是临时token,后台通过接口返回临时token,token包含了可以操作的bucket,文件夹,文件读写权限等等,前端使用临时token上传文件,token有效期可以后台设置,这样就把控制权交给了后台
选择实现方式
最好添加到网关层面,只需要代理s3部分接口并实现鉴权即可
比如 nginx + lua 脚本 kong + lua插件
Java 分块代码分析
MinioClient.java 4371 行 搜索关键字 calculateMultipartSize
/**
* Executes put object. If size of object data is <= 5MiB, single put object is used
* else multipart put object is used.
*
* @param bucketName
* Bucket name.
* @param objectName
* Object name in the bucket.
* @param size
* Size of object data.
* @param data
* Object data.
*/
private void putObject(String bucketName, String objectName, Long size, Object data,
Map<String, String> headerMap, ServerSideEncryption sse, String contentType)
throws InvalidBucketNameException, NoSuchAlgorithmException, IOException,
InvalidKeyException, NoResponseException, XmlPullParserException, ErrorResponseException,
InternalException, InvalidArgumentException, InsufficientDataException, InvalidResponseException {
boolean unknownSize = false;
if (size == null) {
unknownSize = true;
size = MAX_OBJECT_SIZE;
}
if (headerMap == null) {
headerMap = new HashMap<>();
}
// Add content type if not already set
// Content Type being passed as argument has higher precedence
// than the one passed in headerMap if any.
if (contentType == null) {
if (headerMap.get("Content-Type") == null) {
headerMap.put("Content-Type", "application/octet-stream");
}
} else {
headerMap.put("Content-Type", contentType);
}
if (sse != null) {
checkWriteRequestSse(sse);
headerMap.putAll(sse.headers());
}
if (size <= MIN_MULTIPART_SIZE) {
putObject(bucketName, objectName, data, size.intValue(), headerMap, null, 0);
return;
}
/* Multipart upload 分块上传 */
int[] rv = calculateMultipartSize(size);
int partSize = rv[0];
int partCount = rv[1];
int lastPartSize = rv[2];
Part[] totalParts = new Part[partCount];
// initiate new multipart upload.
String uploadId = initMultipartUpload(bucketName, objectName, headerMap);
try {
int expectedReadSize = partSize;
for (int partNumber = 1; partNumber <= partCount; partNumber++) {
if (partNumber == partCount) {
expectedReadSize = lastPartSize;
}
// For unknown sized stream, check available size. 未知大小的数据 一般是直播监控等场景使用
int availableSize = 0;
if (unknownSize) {
// Check whether data is available one byte more than expectedReadSize.
availableSize = getAvailableSize(data, expectedReadSize + 1);
// If availableSize is less or equal to expectedReadSize, then we reached last part.
if (availableSize <= expectedReadSize) {
// If it is first part, do single put object.
if (partNumber == 1) {
putObject(bucketName, objectName, data, availableSize, headerMap, null, 0);
return;
}
expectedReadSize = availableSize;
partCount = partNumber;
}
}
Map<String, String> encryptionHeaders = null;
// In multi-part uploads, set encryption headers in the case of SSE-C.
if (sse != null && sse.type() == ServerSideEncryption.Type.SSE_C) {
encryptionHeaders = sse.headers();
}
String etag = putObject(bucketName, objectName, data, expectedReadSize, encryptionHeaders,
uploadId, partNumber);
totalParts[partNumber - 1] = new Part(partNumber, etag);
}
// All parts have been uploaded, complete the multipart upload. 所有的数据块上传成功就会合并文件
completeMultipart(bucketName, objectName, uploadId, totalParts);
} catch (RuntimeException e) {
abortMultipartUpload(bucketName, objectName, uploadId);
throw e;
} catch (Exception e) {
abortMultipartUpload(bucketName, objectName, uploadId);
throw e;
}
}
进阶
断点续传协议
tus协议
https://tus.io/
前端上传文件sdk
Uppy 框架
https://uppy.io/
