/// <summary>
/// Asynchronously enumerates the topics in this board.
/// </summary>
/// <param name="options">Enumeration options.</param>
/// <param name="pageSize">
/// How many topics should be fetched in batch per MediaWiki API request.
/// No more than 100 (100 for bots) is allowed.
/// </param>
public async IAsyncEnumerable <Topic> EnumTopicsAsync(TopicListingOptions options, int pageSize,
[EnumeratorCancellation] CancellationToken cancellationToken = default)
{
if (pageSize <= 0)
{
throw new ArgumentOutOfRangeException(nameof(pageSize));
}
var sortParam = "user";
if ((options & TopicListingOptions.OrderByPosted) == TopicListingOptions.OrderByPosted)
{
sortParam = "newest";
}
if ((options & TopicListingOptions.OrderByUpdated) == TopicListingOptions.OrderByUpdated)
{
sortParam = "updated";
}
var queryParams = new Dictionary <string, object>
{
{ "action", "flow" },
{ "submodule", "view-topiclist" },
{ "page", Title },
{ "vtlsortby", sortParam },
{ "vtlsavesortby", (options & TopicListingOptions.SaveSortingPreference) == TopicListingOptions.SaveSortingPreference },
{ "vtllimit", pageSize },
{ "vtlformat", "wikitext" },
};
NEXT_PAGE:
var jresult = await Site.InvokeMediaWikiApiAsync(new MediaWikiFormRequestMessage(queryParams), cancellationToken);
var jtopiclist = (JObject)jresult["flow"]["view-topiclist"]["result"]["topiclist"];
using (ExecutionContextStash.Capture())
foreach (var t in Topic.FromJsonTopicList(Site, jtopiclist))
{
yield return(t);
}
// 2018-07-30 flow.view-topiclist.result.topiclist.links.pagination is [] instead of null for boards without pagination.
var jpagination = jtopiclist["links"]?["pagination"];
var nextPageUrl = jpagination == null || jpagination is JArray
? null
: (string)jpagination["fwd"]?["url"];
if (nextPageUrl != null)
{
var urlParams = FlowUtility.ParseUrlQueryParametrs(nextPageUrl);
foreach (var pa in urlParams)
{
if (pa.Key.StartsWith("topiclist_"))
{
queryParams["vtl" + pa.Key[10..]] = pa.Value;
/// <inheritdoc cref="EnumTopicsAsync(TopicListingOptions, int, CancellationToken)"/>
public IAsyncEnumerable <Topic> EnumTopicsAsync(TopicListingOptions options)
{
return(EnumTopicsAsync(options, 20));
}