本文介绍如何使用分片上传。
上传文件
分片上传（Multipart Upload）分为以下三个步骤：
初始化一个分片上传事件。
调用initiateMultipartUpload方法返回OSS创建的全局唯一的uploadId。
上传分片。
调用uploadPart方法上传分片数据。
完成分片上传。
所有分片上传完成后，调用completeMultipartUpload方法将所有分片合并成完整的文件。
以下通过一个完整的示例对分片上传的流程进行逐步解析：
let key = "multipart-test"
var uploadId : String?
var parts : Array<AWSS3CompletedPart>?
// 初始化分片上传
let createMultipartReq = AWSS3CreateMultipartUploadRequest.init()
createMultipartReq?.bucket = S3BucketName
createMultipartReq?.key = key
s3.createMultipartUpload(createMultipartReq!).continueWith(block: { (task:AWSTask<AWSS3CreateMultipartUploadOutput>) -> Any? in
if let error = task.error {
print("create multipart request failed with error: (\(error))")
} else {
uploadId = task.result?.uploadId
print("create muiltipart completed!" + uploadId!)
}
return nil
})
// 上传一个分片
let uploadPartReq = AWSS3UploadPartRequest.init()
let databody:NSData? = "MY TEST MULTIPART UPLOAD!".data(using: .utf8) as NSData?
uploadPartReq?.bucket = S3BucketName
uploadPartReq?.key = key
uploadPartReq?.partNumber = 1
uploadPartReq?.body = databody
s3.uploadPart(uploadPartReq!).continueWith(block: { (task:AWSTask<AWSS3UploadPartOutput>) -> Any? in
if let error = task.error {
print("upload part failed with error: (\(error))")
} else {
let info = AWSS3CompletedPart.init()
info?.eTag = task.result?.eTag
info?.partNumber = 1
parts = [info!]
print("upload completed.")
}
return nil
})
// 完成分片上传
let completinfo = AWSS3CompletedMultipartUpload.init()
if parts == nil {
print("no part")
return
}
completinfo?.parts = parts ?? []
let complete = AWSS3CompleteMultipartUploadRequest.init()
complete?.bucket = S3BucketName
complete?.key = key
complete?.uploadId = uploadId
complete?.multipartUpload = completinfo
s3.completeMultipartUpload(complete!).continueWith(block: { (task) -> Any? in
if let error = task.error {
print("multipart upload failed with error: (\(error))")
} else {
print("multipart upload completed!")
}
return nil
}) |
取消分片上传事件
您可以调用abortMultipartUpload方法来取消分片上传事件。当一个分片上传事件被取消后，无法再使用这个uploadId做任何操作，已经上传的分片数据会被删除。
以下代码用于取消分片上传事件：
var uploads : Array<AWSS3MultipartUpload>?
let listpartreq = AWSS3ListMultipartUploadsRequest.init()
listpartreq?.bucket = S3BucketName
s3.listMultipartUploads(listpartreq!).continueWith(block: { (task:AWSTask<AWSS3ListMultipartUploadsOutput>) -> Any? in
if let error = task.error {
print("list parts failed with error: (\(error))")
} else {
let count = task.result?.uploads?.count
if count == nil {
print("there not have multipart upload(s) in progress.")
uploads = Array.init()
return nil
}s
// 取消分片
uploads = task.result?.uploads
for upload in uploads! {
let abortreq = AWSS3AbortMultipartUploadRequest.init()
abortreq?.bucket = self.S3BucketName
abortreq?.key = upload.key
abortreq?.uploadId = upload.uploadId
s3.abortMultipartUpload(abortreq!).continueWith(block: { (task) -> Any? in
if let error = task.error {
print("abort parts failed with error: (\(error))")
} else {
print("abort parts completed!")
}
return nil
})
}
}
return nil
}) |
列举正在上传的分片
以下代码用于简单列举正在上传的分片：
let listpartreq = AWSS3ListMultipartUploadsRequest.init()
listpartreq?.bucket = S3BucketName
s3.listMultipartUploads(listpartreq!).continueWith(block: { (task:AWSTask<AWSS3ListMultipartUploadsOutput>) -> Any? in
if let error = task.error {
print("list parts failed with error: (\(error))")
} else {
let count = task.result?.uploads?.count
if count == nil {
print(" there not have multipart upload(s) in progress.")
return nil
}
print(" \(count!) multipart upload(s) in progress.")
print("list parts completed!")
}
return nil
}) |
