2025-07-01 00:44:48 +08:00

139 lines
4.4 KiB
C#

using System.ServiceModel.Syndication;
using System.Xml;
using Microsoft.EntityFrameworkCore;
namespace DysonNetwork.Sphere.Connection.WebReader;
public class WebFeedService(
AppDatabase database,
IHttpClientFactory httpClientFactory,
ILogger<WebFeedService> logger,
WebReaderService webReaderService
)
{
public async Task<WebFeed> CreateWebFeedAsync(Publisher.Publisher publisher,
WebFeedController.WebFeedRequest request)
{
var feed = new WebFeed
{
Url = request.Url!,
Title = request.Title!,
Description = request.Description,
Config = request.Config ?? new WebFeedConfig(),
PublisherId = publisher.Id,
};
database.Set<WebFeed>().Add(feed);
await database.SaveChangesAsync();
return feed;
}
public async Task<WebFeed?> GetFeedAsync(Guid id, Guid? publisherId = null)
{
var query = database.WebFeeds.Where(a => a.Id == id).AsQueryable();
if (publisherId.HasValue)
query = query.Where(a => a.PublisherId == publisherId.Value);
return await query.FirstOrDefaultAsync();
}
public async Task<List<WebFeed>> GetFeedsByPublisherAsync(Guid publisherId)
{
return await database.WebFeeds.Where(a => a.PublisherId == publisherId).ToListAsync();
}
public async Task<WebFeed> UpdateFeedAsync(WebFeed feed, WebFeedController.WebFeedRequest request)
{
if (request.Url is not null)
feed.Url = request.Url;
if (request.Title is not null)
feed.Title = request.Title;
if (request.Description is not null)
feed.Description = request.Description;
if (request.Config is not null)
feed.Config = request.Config;
database.Update(feed);
await database.SaveChangesAsync();
return feed;
}
public async Task<bool> DeleteFeedAsync(Guid id)
{
var feed = await database.WebFeeds.FindAsync(id);
if (feed == null)
{
return false;
}
database.WebFeeds.Remove(feed);
await database.SaveChangesAsync();
return true;
}
public async Task ScrapeFeedAsync(WebFeed feed, CancellationToken cancellationToken = default)
{
var httpClient = httpClientFactory.CreateClient();
var response = await httpClient.GetAsync(feed.Url, cancellationToken);
response.EnsureSuccessStatusCode();
await using var stream = await response.Content.ReadAsStreamAsync(cancellationToken);
using var reader = XmlReader.Create(stream);
var syndicationFeed = SyndicationFeed.Load(reader);
if (syndicationFeed == null)
{
logger.LogWarning("Could not parse syndication feed for {FeedUrl}", feed.Url);
return;
}
foreach (var item in syndicationFeed.Items)
{
var itemUrl = item.Links.FirstOrDefault()?.Uri.ToString();
if (string.IsNullOrEmpty(itemUrl))
{
continue;
}
var articleExists = await database.Set<WebArticle>()
.AnyAsync(a => a.FeedId == feed.Id && a.Url == itemUrl, cancellationToken);
if (articleExists)
{
continue;
}
var content = (item.Content as TextSyndicationContent)?.Text ?? item.Summary.Text;
LinkEmbed preview;
if (feed.Config.ScrapPage)
{
var scrapedArticle = await webReaderService.ScrapeArticleAsync(itemUrl, cancellationToken);
preview = scrapedArticle.LinkEmbed;
if (scrapedArticle.Content is not null)
content = scrapedArticle.Content;
}
else
{
preview = await webReaderService.GetLinkPreviewAsync(itemUrl, cancellationToken);
}
var newArticle = new WebArticle
{
FeedId = feed.Id,
Title = item.Title.Text,
Url = itemUrl,
Author = item.Authors.FirstOrDefault()?.Name,
Content = content,
PublishedAt = item.PublishDate.UtcDateTime,
Preview = preview,
};
database.Set<WebArticle>().Add(newArticle);
}
await database.SaveChangesAsync(cancellationToken);
}
}