src/advance.js
function uploadSliceList(params, cb) {
    var self = this;
    var TaskId = params.TaskId;
    var Bucket = params.Bucket;
    var Region = params.Region;
    var Key = params.Key;
    var UploadData = params.UploadData;
    var FileSize = params.FileSize;
    var SliceSize = params.SliceSize;
    var ChunkParallel = Math.min(params.AsyncLimit || self.options.ChunkParallelLimit || 1, 256);
    var Body = params.Body;
    var SliceCount = Math.ceil(FileSize / SliceSize);
    var FinishSize = 0;
    var ServerSideEncryption = params.ServerSideEncryption;
    var needUploadSlices = util.filter(UploadData.PartList, function (SliceItem) {
        if (SliceItem['Uploaded']) {
            FinishSize += SliceItem['PartNumber'] >= SliceCount ? (FileSize % SliceSize || SliceSize) : SliceSize;
        }
        return !SliceItem['Uploaded'];
    });
    var onProgress = params.onProgress;

    Async.eachLimit(needUploadSlices, ChunkParallel, function (SliceItem, asyncCallback) {
        if (!self._isRunningTask(TaskId)) return;
        var PartNumber = SliceItem['PartNumber'];
        var currentSize = Math.min(FileSize, SliceItem['PartNumber'] * SliceSize) - (SliceItem['PartNumber'] - 1) * SliceSize;
        var preAddSize = 0;
        uploadSliceItem.call(self, {
            TaskId: TaskId,
            Bucket: Bucket,
            Region: Region,
            Key: Key,
            SliceSize: SliceSize,
            FileSize: FileSize,
            PartNumber: PartNumber,
            ServerSideEncryption: ServerSideEncryption,
            Body: Body,
            UploadData: UploadData,
            onProgress: function (data) {
                FinishSize += data.loaded - preAddSize;
                preAddSize = data.loaded;
                onProgress({loaded: FinishSize, total: FileSize});
            },
        }, function (err, data) {
            if (!self._isRunningTask(TaskId)) return;
            if (util.isBrowser && !err && !data.ETag) {
                err = 'get ETag error, please add "ETag" to CORS ExposeHeader setting.';
            }
            if (err) {
                FinishSize -= preAddSize;
            } else {
                FinishSize += currentSize - preAddSize;
                SliceItem.ETag = data.ETag;
            }
            asyncCallback(err || null, data);
        });
    }, function (err) {
        if (!self._isRunningTask(TaskId)) return;
        if (err)  return cb(err);
        cb(null, {
            UploadId: UploadData.UploadId,
            SliceList: UploadData.PartList
        });
    });
}
function uploadSliceList(params, cb) {
    var self = this;
    var TaskId = params.TaskId;
    var Bucket = params.Bucket;
    var Region = params.Region;
    var Key = params.Key;
    var UploadData = params.UploadData;
    var FileSize = params.FileSize;
    var SliceSize = params.SliceSize;
    var ChunkParallel = Math.min(params.AsyncLimit || self.options.ChunkParallelLimit || 1, 256);
    var Body = params.Body;
    var SliceCount = Math.ceil(FileSize / SliceSize);
    var FinishSize = 0;
    var ServerSideEncryption = params.ServerSideEncryption;
    var needUploadSlices = util.filter(UploadData.PartList, function (SliceItem) {
        if (SliceItem['Uploaded']) {
            FinishSize += SliceItem['PartNumber'] >= SliceCount ? (FileSize % SliceSize || SliceSize) : SliceSize;
        }
        return !SliceItem['Uploaded'];
    });
    var onProgress = params.onProgress;

    Async.eachLimit(needUploadSlices, ChunkParallel, function (SliceItem, asyncCallback) {
        if (!self._isRunningTask(TaskId)) return;
        var PartNumber = SliceItem['PartNumber'];
        var currentSize = Math.min(FileSize, SliceItem['PartNumber'] * SliceSize) - (SliceItem['PartNumber'] - 1) * SliceSize;
        var preAddSize = 0;
        uploadSliceItem.call(self, {
            TaskId: TaskId,
            Bucket: Bucket,
            Region: Region,
            Key: Key,
            SliceSize: SliceSize,
            FileSize: FileSize,
            PartNumber: PartNumber,
            ServerSideEncryption: ServerSideEncryption,
            Body: Body,
            UploadData: UploadData,
            onProgress: function (data) {
                FinishSize += data.loaded - preAddSize;
                preAddSize = data.loaded;
                onProgress({loaded: FinishSize, total: FileSize});
            },
        }, function (err, data) {
            if (!self._isRunningTask(TaskId)) return;
            if (util.isBrowser && !err && !data.ETag) {
                err = 'get ETag error, please add "ETag" to CORS ExposeHeader setting.';
            }
            if (err) {
                FinishSize -= preAddSize;
            } else {
                FinishSize += currentSize - preAddSize;
                SliceItem.ETag = data.ETag;
            }
            asyncCallback(err || null, data);
        });
    }, function (err) {
        if (!self._isRunningTask(TaskId)) return;
        if (err)  return cb(err);
        cb(null, {
            UploadId: UploadData.UploadId,
            SliceList: UploadData.PartList
        });
    });
}
上传文件分块，包括 /*
UploadId (上传任务编号)
AsyncLimit (并发量)，
SliceList (上传的分块数组)，
FilePath (本地文件的位置)，
SliceSize (文件分块大小)
FileSize (文件大小)
onProgress (上传成功之后的回调函数)