private async Task <SyndicationFeed> GetFeedAsync(GetSyndicationFeedQuery request, CancellationToken cancellationToken)
{
var blog = new BlogModel(_blogOptions.Value);
var feed = new SyndicationFeed
{
Title = new TextSyndicationContent(blog.Title),
Description = new TextSyndicationContent("Latest blog posts"),
BaseUri = request.BaseUri,
Items = await GetItemsAsync(request, cancellationToken),
};
// TODO: handle relative URLs, add a helper method for making them absolute. Also for the meta data on the home page
if (!string.IsNullOrWhiteSpace(blog.CoverUrl) && blog.CoverUrl.StartsWith("http"))
{
feed.ImageUrl = new Uri(blog.CoverUrl);
}
feed.Links.Add(new SyndicationLink(feed.BaseUri));
feed.Copyright = new TextSyndicationContent("Copyright " + DateTime.UtcNow.Year);
feed.LastUpdatedTime = DateTime.UtcNow;
if (feed.Items.Any())
{
feed.Contributors.Add(feed.Items.First().Authors.First());
}
return(feed);
}
/// <summary>
/// Handle the GetFeedQuery request.
/// </summary>
/// <param name="request">The GetFeedQuery request.</param>
/// <param name="cancellationToken">A cancellation token.</param>
public async Task <Result <FeedModel> > Handle(GetSyndicationFeedQuery request, CancellationToken cancellationToken)
{
var feed = await GetFeedAsync(request, cancellationToken);
var model = new FeedModel();
if (request.FeedType == FeedType.Atom)
{
model.ContentType = "application/atom+xml";
}
else if (request.FeedType == FeedType.Rss)
{
model.ContentType = "application/rss+xml";
}
var feedWriter = new StringWriter();
using (var xmlWriter = new XmlTextWriter(feedWriter))
{
xmlWriter.Formatting = Formatting.Indented;
if (request.FeedType == FeedType.Atom)
{
feed.SaveAsAtom10(xmlWriter);
}
else if (request.FeedType == FeedType.Rss)
{
feed.SaveAsRss20(xmlWriter);
}
}
model.Feed = feedWriter.ToString();
return(Result <FeedModel> .Success(model));
}
private async Task <IEnumerable <SyndicationItem> > GetItemsAsync(GetSyndicationFeedQuery request, CancellationToken cancellationToken)
{
var posts = await _uow.Posts.GetPublishedAsync(25, cancellationToken);
var items = new List <SyndicationItem>();
foreach (var post in posts.AsQueryable().Select(p => _postUrlHelper.ReplaceUrlFormatWithBaseUrl(p)))
{
var absoluteUrl = new Uri(request.BaseUri, $"{request.PostBasePath}/{post.Slug}");
var content = SyndicationContent.CreateHtmlContent(Markdig.Markdown.ToHtml(post.Content));
var item = new SyndicationItem(post.Title, content, absoluteUrl, absoluteUrl.ToString(), post.Modified)
{
PublishDate = post.Published.Value
};
if (!string.IsNullOrWhiteSpace(post.Description))
{
item.Summary = new TextSyndicationContent(post.Description);
}
if (!string.IsNullOrWhiteSpace(post.Categories))
{
foreach (var category in post.Categories.Split(','))
{
item.Categories.Add(new SyndicationCategory(category));
}
}
item.Authors.Add(new SyndicationPerson("", post.Author.DisplayName, request.BaseUri.ToString()));
items.Add(item);
}
return(items);
}
