private void Download(string url, CancellationToken cancellationToken)
        {
            DebugLogger.Log(string.Format("Trying to download from {0}", url));
            
            var offset = CurrentFileSize();

            DebugLogger.LogVariable(offset, "offset");

            BaseHttpDownloader baseHttpDownloader = new BaseHttpDownloader(url, _timeout);
            baseHttpDownloader.SetBytesRange(offset);

            baseHttpDownloader.DataAvailable += (bytes, length) =>
            {
                bool retry = !_fileStream.Write(bytes, 0, length);

                if (retry)
                {
                    throw new DownloaderException("Corrupt data.", DownloaderExceptionStatus.CorruptData);
                }

                OnDownloadProgressChanged(CurrentFileSize(), _resource.Size);
            };

            baseHttpDownloader.Download(cancellationToken);
            
            if (_fileStream.RemainingLength > 0)
            {
                throw new DownloaderException("Data download hasn't been completed.", DownloaderExceptionStatus.Other);
            }
        }
Ejemplo n.º 2
0
        private bool TryDownload(ResourceUrl url, ChunkedFileStream fileStream, CancellationToken cancellationToken)
        {
            try
            {
                _logger.LogDebug(string.Format("Trying to download from {0}", url.Url));
                _logger.LogTrace("fileStream.VerifiedLength = " + fileStream.VerifiedLength);

                var downloadJobQueue = BuildDownloadJobQueue(url, fileStream.VerifiedLength);
                foreach (var downloadJob in downloadJobQueue)
                {
                    _logger.LogDebug(string.Format("Executing download job {0} with offest {1}", downloadJob.Url,
                                                   downloadJob.Range.Start));
                    _logger.LogTrace("fileStream.VerifiedLength = " + fileStream.VerifiedLength);
                    _logger.LogTrace("fileStream.SavedLength = " + fileStream.SavedLength);

                    var baseHttpDownloader = new BaseHttpDownloader(downloadJob.Url, 30000);
                    baseHttpDownloader.SetBytesRange(downloadJob.Range);

                    const long downloadStatusLogInterval = 5000L;
                    var        stopwatch = Stopwatch.StartNew();

                    long downloadedBytes = 0;

                    var job = downloadJob;
                    baseHttpDownloader.DataAvailable += (bytes, length) =>
                    {
                        fileStream.Write(bytes, 0, length);

                        downloadedBytes += length;

                        if (stopwatch.ElapsedMilliseconds > downloadStatusLogInterval)
                        {
                            stopwatch.Reset();
                            stopwatch.Start();

                            _logger.LogDebug(string.Format("Downloaded {0} from {1}", downloadedBytes, job.Url));
                            _logger.LogTrace("fileStream.VerifiedLength = " + fileStream.VerifiedLength);
                            _logger.LogTrace("fileStream.SavedLength = " + fileStream.SavedLength);
                        }

                        OnDownloadProgressChanged(fileStream.VerifiedLength);
                    };

                    baseHttpDownloader.Download(cancellationToken);

                    _logger.LogDebug("Download job execution success.");
                    _logger.LogTrace("fileStream.VerifiedLength = " + fileStream.VerifiedLength);
                    _logger.LogTrace("fileStream.SavedLength = " + fileStream.SavedLength);
                }

                if (fileStream.RemainingLength != 0)
                {
                    throw new IncompleteDataException("Chunks downloading must finish downloading whole file");
                }

                _logger.LogDebug(string.Format("Download from {0} has been successful.", url.Url));
                return(true);
            }
            catch (IncompleteDataException e)
            {
                _logger.LogWarning(string.Format("Unable to download from {0}", url.Url), e);
                return(false);
            }
            catch (InvalidChunkDataException e)
            {
                _logger.LogWarning(string.Format("Unable to download from {0}", url.Url), e);
                return(false);
            }
            catch (DataNotAvailableException e)
            {
                _logger.LogWarning(string.Format("Unable to download from {0}", url.Url), e);
                return(false);
            }
            catch (ServerErrorException e)
            {
                _logger.LogWarning(string.Format("Unable to download from {0}", url.Url), e);
                return(false);
            }
            catch (ConnectionFailureException e)
            {
                _logger.LogWarning(string.Format("Unable to download from {0}", url.Url), e);
                return(false);
            }
        }