private TransferMetadata CreateMetadata(int segmentCount)
{
var path = Path.GetTempFileName();
var metadata = new TransferMetadata()
{
MetadataFilePath = path,
InputFilePath = _smallFilePath,
FileLength = _smallFileContents.Length,
SegmentCount = segmentCount,
SegmentLength = TransferSegmentMetadata.CalculateSegmentLength(_smallFileContents.Length, segmentCount),
Segments = new TransferSegmentMetadata[segmentCount],
TargetStreamPath = "abc",
TransferId = "123",
IsBinary = true
};
long offset = 0;
for (int i = 0; i < segmentCount; i++)
{
long length = TransferSegmentMetadata.CalculateSegmentLength(i, metadata);
metadata.Segments[i] = new TransferSegmentMetadata()
{
SegmentNumber = i,
Offset = offset,
Status = SegmentTransferStatus.Pending,
Length = length,
Path = string.Format("{0}.{1}.segment{2}", metadata.TargetStreamPath, metadata.TransferId, i)
};
offset += length;
}
return(metadata);
}
public void UploadSegmentMetadata_CalculateTypicalSegmentLength()
{
Assert.Throws <ArgumentException>(() => { TransferSegmentMetadata.CalculateSegmentLength(1000, -1); });
const int maxSegmentCount = 16536;
long fileLength = (long)Math.Pow(2, 30); // see comment below about actually making this larger than Int32.MaxValue
long segmentLength;
for (int segmentCount = 1; segmentCount < maxSegmentCount; segmentCount++)
{
segmentLength = TransferSegmentMetadata.CalculateSegmentLength(fileLength, segmentCount);
//the next two asserts verify that the value calculated will split the input file into a balanced set of segments;
//all the segments should have the same length, except the last one which may have less than that (but never more).
//a quick heuristic to verify this is: (SegmentLength-1)*SegmentCount < FileLength <= SegmentLength*SegmentCount
Assert.True(segmentLength * segmentCount >= fileLength, "SegmentLength * SegmentCount must be at least the length of the input file");
Assert.True((segmentLength - 1) * segmentCount < fileLength, "(SegmentLength - 1) * SegmentCount must be smaller than the length of the input file");
}
// test segmentCount == fileLength;
segmentLength = TransferSegmentMetadata.CalculateSegmentLength(fileLength, (int)fileLength); //for this to work, FileLength must be less than In32.MaxValue
Assert.Equal(1, segmentLength);
// test that if segment count = 0 then the return value is 0.
Assert.Equal(
0,
TransferSegmentMetadata.CalculateSegmentLength(fileLength, 0));
}
public void UploadSegmentMetadata_CalculateParticularSegmentLength()
{
//verify bad inputs
Assert.Throws <ArgumentOutOfRangeException>(
() => { TransferSegmentMetadata.CalculateSegmentLength(-1, new TransferMetadata()
{
FileLength = 10, SegmentCount = 5, SegmentLength = 2
}); });
Assert.Throws <ArgumentOutOfRangeException>(
() => { TransferSegmentMetadata.CalculateSegmentLength(100, new TransferMetadata()
{
FileLength = 10, SegmentCount = 5, SegmentLength = 2
}); });
Assert.Throws <ArgumentException>(
() => { TransferSegmentMetadata.CalculateSegmentLength(1, new TransferMetadata()
{
FileLength = -10, SegmentCount = 5, SegmentLength = 2
}); });
Assert.Throws <ArgumentException>(
() => { TransferSegmentMetadata.CalculateSegmentLength(1, new TransferMetadata()
{
FileLength = 100, SegmentCount = 2, SegmentLength = 2
}); });
Assert.Throws <ArgumentException>(
() => { TransferSegmentMetadata.CalculateSegmentLength(1, new TransferMetadata()
{
FileLength = 100, SegmentCount = 5, SegmentLength = 26
}); });
//test various scenarios with a fixed file length, and varying the segment count from 1 to the FileLength
int FileLength = 16 * (int)Math.Pow(2, 20);//16MB
for (int segmentCount = 1; segmentCount <= FileLength; segmentCount += 1024)
{
long typicalSegmentLength = TransferSegmentMetadata.CalculateSegmentLength(FileLength, segmentCount);
var uploadMetadata = new TransferMetadata()
{
FileLength = FileLength, SegmentCount = segmentCount, SegmentLength = typicalSegmentLength
};
long firstSegmentLength = TransferSegmentMetadata.CalculateSegmentLength(0, uploadMetadata);
long lastSegmentLength = TransferSegmentMetadata.CalculateSegmentLength(segmentCount - 1, uploadMetadata);
Assert.Equal(typicalSegmentLength, firstSegmentLength);
if (segmentCount == 1)
{
Assert.Equal(firstSegmentLength, lastSegmentLength);
}
long reconstructedFileLength = typicalSegmentLength * (segmentCount - 1) + lastSegmentLength;
Assert.Equal(FileLength, reconstructedFileLength);
}
}
private TransferMetadata CreateMetadata(string filePath, long fileLength)
{
var metadata = new TransferMetadata()
{
InputFilePath = filePath,
FileLength = fileLength,
TargetStreamPath = StreamPath,
SegmentCount = 1,
SegmentLength = TransferSegmentMetadata.CalculateSegmentLength(fileLength, 1),
Segments = new TransferSegmentMetadata[1],
IsBinary = true
};
metadata.Segments[0] = new TransferSegmentMetadata(0, metadata);
metadata.Segments[0].Path = metadata.TargetStreamPath;
return(metadata);
}