/// <summary>
/// Creates the indexer.
/// </summary>
/// <returns></returns>
private LuceneIndexer GetIndexer()
{
if (_indexer == null)
{
_indexer = new LuceneIndexer(this._indexModifier, _feedSources);
}
return(_indexer);
}
/// <summary>
/// Remove the feed (and all it's items) from the lucene search index.
/// </summary>
/// <param name="feedID">The feed url.</param>
public void IndexRemove(string feedID)
{
if (!UseIndex || string.IsNullOrEmpty(feedID))
{
return;
}
try {
LuceneIndexer indexer = GetIndexer();
indexer.RemoveFeed(feedID);
} catch (Exception ex) {
Log.Error("Failure while remove item(s) from search index.", ex);
}
}
/// <summary>
/// Remove the list of NewsItems from the lucene search index.
/// </summary>
/// <param name="newsItems">The news items list.</param>
public void IndexRemove(INewsItem[] newsItems)
{
if (!UseIndex || newsItems == null)
{
return;
}
try {
LuceneIndexer indexer = GetIndexer();
indexer.RemoveNewsItems(newsItems);
} catch (Exception ex) {
Log.Error("Failure while remove item(s) from search index.", ex);
}
}
/// <summary>
/// Add the list of NewsItems to the lucene search index.
/// </summary>
/// <param name="newsItems">The news items list.</param>
public void IndexAdd(IList <INewsItem> newsItems)
{
if (!UseIndex || newsItems == null)
{
return;
}
try {
LuceneIndexer indexer = GetIndexer();
indexer.IndexNewsItems(newsItems);
} catch (Exception ex) {
Log.Error("Failure while add item(s) to search index.", ex);
}
}
// /// <summary>
// /// Re-Index a feed. First, the feed gets removed completely from index,
// /// then the items are added to index again.
// /// </summary>
// /// <param name="feedID">The feed URL.</param>
// /// <param name="newsItems">The news items.</param>
// public void ReIndex(string feedID, IList newsItems) {
// if (!UseIndex) return;
// //WASTODO: way too general, we should optimize that:
// // re-indexing only the really new items, and remove only
// // the purged items:
// this.IndexRemove(feedID);
// this.IndexAdd(newsItems);
// }
/// <summary>
/// Re-Index a feed. First, the feed gets removed completely from index,
/// then the items are added to index again.
/// </summary>
/// <param name="feed">The feed.</param>
/// <param name="items">The NewsItems belonging to the feed</param>
public void ReIndex(INewsFeed feed, IList <INewsItem> items)
{
if (!UseIndex || feed == null)
{
return;
}
try {
LuceneIndexer indexer = GetIndexer();
indexer.RemoveNewsItems(feed.id);
indexer.IndexNewsItems(items);
} catch (Exception ex) {
Log.Error("Failure while ReIndex item(s) in search index.", ex);
}
//this.IndexRemove(feed.id);
//this.IndexAdd(newsHandler.GetCachedItemsForFeed(feed.link));
}
/// <summary>
/// Checks the index. If it does not exists, this will start
/// creating a new index. This process is recoverable/restartable and
/// can/should be called each time the Search is expected to be used.
/// </summary>
/// <param name="force">if set to <c>true</c> a re-indexing of all
/// items is started.</param>
public void CheckIndex(bool force)
{
if (!UseIndex)
{
return;
}
bool restartIndexing = false;
bool fileBasedIndex = this._settings.IndexPath != null &&
Directory.Exists(this._settings.IndexPath);
string indexingStateFile = this.RestartIndexingStateFile;
DateTime indexModifiedAt = DateTime.MinValue;
if (fileBasedIndex)
{
indexModifiedAt = Directory.GetLastWriteTimeUtc(this._settings.IndexPath);
bool indexStateFileExists = (indexingStateFile != null && File.Exists(indexingStateFile));
// if the index have to be (re-)created, we don't want to rely on old restart infos:
if ((force || startIndexAll) && indexStateFileExists)
{
FileHelper.Delete(indexingStateFile);
}
// restart indexing: read state and go on with the next non-indexed feed
restartIndexing = (!startIndexAll && indexStateFileExists);
}
else
{
startIndexAll = true;
}
if (force || restartIndexing || startIndexAll)
{
IDictionary restartInfo = null;
DictionaryEntry lastIndexed = new DictionaryEntry();
if (restartIndexing)
{
// read indexState into restartInfo (persisted feed urls/id, that are yet indexed)
restartInfo = ReadIndexingRestartStateFileContent(indexingStateFile, out lastIndexed);
}
if (restartInfo == null)
{
restartInfo = new HybridDictionary();
}
if (startIndexAll)
{
this._indexModifier.CreateIndex();
}
LuceneIndexer indexer = GetIndexer();
indexer.IndexingFinished += OnIndexingFinished;
indexer.IndexingProgress += OnIndexingProgress;
indexer.IndexAll(restartInfo, lastIndexed);
}
else if (fileBasedIndex)
{
// check, if we have to call OptimizeIndex():
DateTime lastIndexModification = this._settings.LastIndexOptimization;
int compareResult = indexModifiedAt.CompareTo(lastIndexModification);
// indexModifiedAt is greater than lastIndexModification, hence index was modified:
if (compareResult > 0)
{
// attach event to get optimize index finished notification:
this._indexModifier.FinishedIndexOperation += OnIndexModifierFinishedIndexOperation;
this.IndexOptimize();
}
else if (compareResult != 0)
{
// correct the bad persisted entry:
this._settings.LastIndexOptimization = Directory.GetLastWriteTimeUtc(this._settings.IndexPath);
}
}
}
