/// <summary>
/// Bumps, or signals creation/completion/status update request, based on the stream's current state.
/// </summary>
/// <param name="streamStatus">Stream status with the source data filled in with info on the stream being signaled</param>
/// <param name="cancellationToken">Used to cancel the operation</param>
/// <returns>Stream status with target details filled in.</returns>
/// <remarks>
/// A returned value with equivalent target and sources hashes and a segment length equal to the full data length,
/// then a completion signal was sent. In this case, <see cref="OnUploadCompleted( string,string)"/> will have been called.
/// Otherwise, data uploading may begin/proceed if the caller has enough info, or the caller may bump again with a more
/// targeted segment length.
/// </remarks>
public async Task <StreamStatus> BumpAsync(StreamStatus streamStatus, CancellationToken cancellationToken = default)
{
try
{
using (var client = new snh.HttpClient())
{
var response = await client.PatchWithAuthenticationAsync(
$"{this.Config.BaseControllerPath}{this.DataSinkControllerPath}",
streamStatus.ToJson(),
this.AuthenticationHeaderGenerator,
this.Logger,
cancellationToken).ConfigureAwait(false);
if (!response.IsSuccessStatusCode)
{
throw new DataSinkHttpClientException("Unsuccessful service call response")
{
ErrorResponse = response
};
}
using (var streamReader = new StreamReader(await response.Content.ReadAsStreamAsync().ConfigureAwait(false)))
using (var jsonTextReader = new JsonTextReader(streamReader))
{
cancellationToken.ThrowIfCancellationRequested();
return(new JsonSerializer().Deserialize <StreamStatus>(jsonTextReader));
}
}
}
catch (Exception ex)
{
this.Logger?.LogError(ex, "Failure to BumpAsync");
throw;
}
}
public async Task <IActionResult> Bump([FromBody] StreamStatus streamStatus, CancellationToken cancellationToken = default)
{
this.Logger?.LogDebug("Processing {Verb} request for {StreamStatus} at {Uri}", this.Request.Method, streamStatus?.ToJson() ?? "{}", this.Request.Path);
var segmentStart = streamStatus.SegmentHashes[0].Start;
var segmentLength = streamStatus.SegmentHashes.Sum(sh => sh.Length);
var partition = this.HttpContextAccessor.HttpContext?.User?.Identity?.Name;
var targetFilePath = this.GetTargetFilePath(partition, streamStatus.Descriptor.Id);
if (!Directory.Exists(Path.GetDirectoryName(targetFilePath)))
{
Directory.CreateDirectory(Path.GetDirectoryName(targetFilePath));
}
using (var targetStream = new FileStream(targetFilePath, FileMode.OpenOrCreate, FileAccess.ReadWrite, FileShare.ReadWrite))
{
switch (targetStream.Length)
{
case long l when l < streamStatus.Descriptor.Length:
// more efficient than SetLength since the file isn't filled with 0s
Logger?.LogInformation($"Setting length of file {targetFilePath} with partition {partition} and ID {streamStatus.Descriptor.Id} to {streamStatus.Descriptor.Length}.");
targetStream.Position = streamStatus.Descriptor.Length - 1;
targetStream.WriteByte(0);
targetStream.Position = 0;
break;
case long l when l > streamStatus.Descriptor.Length:
// truncate the file
Logger?.LogWarning($"Truncating length of file {targetFilePath} with partition {partition} and ID {streamStatus.Descriptor.Id} to {streamStatus.Descriptor.Length}.");
targetStream.SetLength(streamStatus.Descriptor.Length);
break;
}
}
var targetFile = new FileInfo(targetFilePath);
var hasher = new SegmentHasher();
if (hasher.TryGetSubsegmentHashesOfFirstDiff(
streamStatus.SegmentHashes,
targetFile,
segmentStart,
segmentLength,
(byte)streamStatus.SegmentHashes.Length,
new HashAlgorithmName(streamStatus.Descriptor.HashName),
out var diffSubsegmentHashes))
{
Logger?.LogDebug($"Difference was found for the data stream with partition {partition}, ID {streamStatus.Descriptor.Id}, segment start {segmentStart}, and segment length {segmentLength}.");
streamStatus.SegmentHashes = diffSubsegmentHashes;
return(this.Ok(streamStatus));
}
// TODO null segment hashes is a poor indicator of a lack of difference
// and an even poorer indicator that that the OnUploadCompleted event was raised
streamStatus.SegmentHashes = null;
// no diff
// check if we were comparing the full file, and if so, indicate file upload completeness
if (segmentStart == 0 && segmentLength == targetFile.Length)
{
Logger?.LogInformation($"No difference was found for a full data stream with partition {partition} and ID {streamStatus.Descriptor.Id}. Signaling upload completed.");
await this.SignalUploadCompleted(partition, streamStatus.Descriptor.Id, targetFile, cancellationToken).ConfigureAwait(false);
}
else
{
Logger?.LogInformation($"No difference was found for a partial data stream with partition {partition}, ID {streamStatus.Descriptor.Id}, segment start {segmentStart}, and segment length {segmentLength}.");
}
return(this.Ok(streamStatus));
}
