示例#1
0
        /// <inheritdoc/>
        public async Task DownloadAndStoreUrls(List <string> imagesUrls)
        {
            var exitingUrls = await _imagesRepository.GetAllUrls();

            var needToRemove = exitingUrls.Except(imagesUrls).ToList();

            _logger.LogInformation($"Need to remove {needToRemove.Count} images that are no longer relevant");
            foreach (var imageUrlToRemove in needToRemove)
            {
                await _imagesRepository.DeleteImageByUrl(imageUrlToRemove);
            }
            _logger.LogInformation($"Finished removing images, starting downloading and index: {imagesUrls.Count}");
            using (var md5 = MD5.Create())
            {
                var counter = 0;
                Parallel.ForEach(imagesUrls, new ParallelOptions {
                    MaxDegreeOfParallelism = 20
                }, (imageUrl) =>
                {
                    try
                    {
                        Interlocked.Increment(ref counter);
                        if (counter % 100 == 0)
                        {
                            _logger.LogInformation($"Indexed {counter} images of {imagesUrls.Count}");
                        }
                        if (exitingUrls.Contains(imageUrl))
                        {
                            var size = _remoteFileFetcherGateway.GetFileSize(imageUrl).Result;
                            if (size > 0)
                            {
                                return;
                            }
                        }
                        var content = new byte[0];
                        for (int retryIndex = 0; retryIndex < 3; retryIndex++)
                        {
                            try
                            {
                                content = _remoteFileFetcherGateway.GetFileContent(imageUrl).Result.Content;
                                break;
                            }
                            catch
                            {
                                Task.Delay(200).Wait();
                            }
                        }
                        if (content.Length == 0)
                        {
                            _imagesRepository.DeleteImageByUrl(imageUrl).Wait();
                            return;
                        }
                        StoreImage(md5, content, imageUrl).Wait();
                    }
                    catch (Exception ex)
                    {
                        _logger.LogWarning(ex, "There was a problem with the following image url: " + imageUrl + " ");
                    }
                });
            }
        }