/// <summary>
/// Search for NewsItems, that match a provided criteria collection within a optional search scope.
/// </summary>
/// <param name="criteria">SearchCriteriaCollection containing the defined search criteria</param>
/// <param name="scope">Search scope: an array of NewsFeed</param>
/// <param name="tag">optional object to be used by the caller to identify this search</param>
/// <param name="cultureName">Name of the culture.</param>
/// <param name="returnFullItemText">if set to <c>true</c>, full item texts are returned instead of the summery.</param>
public void SearchNewsItems(SearchCriteriaCollection criteria, INewsFeed[] scope, object tag, string cultureName,
bool returnFullItemText)
{
// if scope is an empty array: search all, else search only in spec. feeds
int feedmatches = 0;
int itemmatches = 0;
IList <INewsItem> unreturnedMatchItems = new List <INewsItem>();
var fiList = new FeedInfoList(String.Empty);
Exception ex;
bool valid = SearchHandler.ValidateSearchCriteria(criteria, cultureName, out ex);
if (ex != null) // report always any error (warnings)
{
// render the error in-line (search result):
fiList.Add(FeedSource.CreateHelpNewsItemFromException(ex).FeedDetails);
feedmatches = fiList.Count;
unreturnedMatchItems = fiList.GetAllNewsItems();
itemmatches = unreturnedMatchItems.Count;
}
if (valid)
{
try
{
// do the search (using lucene):
LuceneSearch.Result r = SearchHandler.ExecuteSearch(criteria, scope,
this.Sources.Select(entry => entry.Source), cultureName);
// we iterate r.ItemsMatched to build a
// NewsItemIdentifier and ArrayList list with items, that
// match the read status (if this was a search criteria)
// then call FindNewsItems(NewsItemIdentifier[]) to get also
// the FeedInfoList.
// Raise ONE event, instead of two to return all (counters, lists)
SearchCriteriaProperty criteriaProperty = null;
foreach (ISearchCriteria sc in criteria)
{
criteriaProperty = sc as SearchCriteriaProperty;
if (criteriaProperty != null &&
PropertyExpressionKind.Unread == criteriaProperty.WhatKind)
{
break;
}
}
ItemReadState readState = ItemReadState.Ignore;
if (criteriaProperty != null)
{
readState = criteriaProperty.BeenRead ? ItemReadState.BeenRead : ItemReadState.Unread;
}
if (r != null && r.ItemMatchCount > 0)
{
/* append results */
var nids = new SearchHitNewsItem[r.ItemsMatched.Count];
r.ItemsMatched.CopyTo(nids, 0);
//look in every feed source to find source feed for matching news items
IEnumerable <FeedInfoList> results = Sources.Select(entry => entry.Source.FindNewsItems(nids, readState, returnFullItemText));
foreach (FeedInfoList fil in results)
{
fiList.AddRange(fil);
}
feedmatches = fiList.Count;
unreturnedMatchItems = fiList.GetAllNewsItems();
itemmatches = unreturnedMatchItems.Count;
}
}
catch (Exception searchEx)
{
// render the error in-line (search result):
fiList.Add(FeedSource.CreateHelpNewsItemFromException(searchEx).FeedDetails);
feedmatches = fiList.Count;
unreturnedMatchItems = fiList.GetAllNewsItems();
itemmatches = unreturnedMatchItems.Count;
}
}
RaiseSearchFinishedEvent(tag, fiList, unreturnedMatchItems, feedmatches, itemmatches);
}
/// <summary>
/// Executes a search.
/// </summary>
/// <param name="criteria">The criteria.</param>
/// <param name="scope">The scope.</param>
/// <param name="feedSources">The news handlers.</param>
/// <param name="cultureName">Name of the culture.</param>
/// <returns></returns>
public Result ExecuteSearch(SearchCriteriaCollection criteria, INewsFeed[] scope, IEnumerable <FeedSource> feedSources, string cultureName)
{
if (!UseIndex)
{
return(null);
}
Query q = BuildLuceneQuery(criteria, scope, GetAnalyzer(cultureName));
if (q == null) // not validated
{
return(new Result(0, 0, GetList <SearchHitNewsItem> .Empty, GetArrayList.Empty));
}
//TODO: to be fixed -
// next line causes issues with concurrent thread access to the search index:
IndexSearcher searcher = new IndexSearcher(this._settings.GetIndexDirectory());
Hits hits = null;
while (hits == null)
{
try {
DateTime start = DateTime.Now;
hits = searcher.Search(q, Sort.RELEVANCE);
TimeSpan timeRequired = TimeSpan.FromTicks(DateTime.Now.Ticks - start.Ticks);
_log.Info(String.Format("Found {0} document(s) that matched query '{1}' (time required: {2})", hits.Length(), q, timeRequired));
} catch (BooleanQuery.TooManyClauses) {
BooleanQuery.SetMaxClauseCount(BooleanQuery.GetMaxClauseCount() * 2);
_log.Info(String.Format("Search failed with error 'BooleanQuery.TooManyClauses'. Retry with BooleanQuery.MaxClauseCount == {0}", BooleanQuery.GetMaxClauseCount()));
}
}
List <SearchHitNewsItem> items = new List <SearchHitNewsItem>(hits.Length());
HybridDictionary matchedFeeds = new HybridDictionary();
for (int i = 0; i < hits.Length(); i++)
{
Document doc = hits.Doc(i);
INewsFeed f = null;
string feedLink = doc.Get(Keyword.FeedLink);
if (matchedFeeds.Contains(feedLink))
{
f = (INewsFeed)matchedFeeds[feedLink];
}
if (f == null)
{
foreach (FeedSource h in feedSources)
{
if (h.IsSubscribed(feedLink))
{
f = h.GetFeeds()[feedLink];
break;
}
}
}
if (f == null)
{
continue;
}
SearchHitNewsItem item = new SearchHitNewsItem(f,
doc.Get(Keyword.ItemTitle),
doc.Get(Keyword.ItemLink),
doc.Get(IndexDocument.ItemSummary),
doc.Get(Keyword.ItemAuthor),
new DateTime(DateTools.StringToTime(doc.Get(Keyword.ItemDate))),
LuceneNewsItemSearch.NewsItemIDFromUID(doc.Get(IndexDocument.ItemID)));
items.Add(item);
if (!matchedFeeds.Contains(feedLink))
{
matchedFeeds.Add(feedLink, f);
}
}
return(new Result(items.Count, matchedFeeds.Count, items, new ArrayList(matchedFeeds.Values)));
}
