internal void UpdateIndex()
{
Log.I(Database.Tag, "Re-indexing view {0} ...", Name);
System.Diagnostics.Debug.Assert((Map != null));
if (Id <= 0)
{
var msg = string.Format("View.Id <= 0");
throw new CouchbaseLiteException(msg, new Status(StatusCode.NotFound));
}
var result = new Status(StatusCode.InternalServerError);
Cursor cursor = null;
Cursor cursor2 = null;
try
{
Database.RunInTransaction(() =>
{
var lastSequence = LastSequenceIndexed;
var dbMaxSequence = Database.LastSequenceNumber;
if (lastSequence >= dbMaxSequence)
{
// nothing to do (eg, kCBLStatusNotModified)
Log.V(Database.Tag, "lastSequence ({0}) == dbMaxSequence ({1}), nothing to do", lastSequence, dbMaxSequence);
result.SetCode(StatusCode.NotModified);
return(false);
}
// First remove obsolete emitted results from the 'maps' table:
var sequence = lastSequence;
if (lastSequence < 0)
{
var msg = string.Format("lastSequence < 0 ({0})", lastSequence);
throw new CouchbaseLiteException(msg, new Status(StatusCode.InternalServerError));
}
if (lastSequence == 0)
{
// If the lastSequence has been reset to 0, make sure to remove
// any leftover rows:
var whereArgs = new string[] { Id.ToString() };
Database.StorageEngine.Delete("maps", "view_id=?", whereArgs);
}
else
{
Database.OptimizeSQLIndexes();
// Delete all obsolete map results (ones from since-replaced
// revisions):
var args = new [] {
Id.ToString(),
lastSequence.ToString(),
lastSequence.ToString()
};
Database.StorageEngine.ExecSQL(
"DELETE FROM maps WHERE view_id=? AND sequence IN ("
+ "SELECT parent FROM revs WHERE sequence>? " + "AND +parent>0 AND +parent<=?)",
args);
}
var deleted = 0;
cursor = Database.StorageEngine.IntransactionRawQuery("SELECT changes()");
cursor.MoveToNext();
deleted = cursor.GetInt(0);
cursor.Close();
// Find a better way to propagate this back
// Now scan every revision added since the last time the view was indexed:
var selectArgs = new[] { lastSequence.ToString(), dbMaxSequence.ToString() };
cursor = Database.StorageEngine.IntransactionRawQuery("SELECT revs.doc_id, sequence, docid, revid, json, no_attachments FROM revs, docs "
+ "WHERE sequence>? AND sequence<=? AND current!=0 AND deleted=0 "
+ "AND revs.doc_id = docs.doc_id "
+ "ORDER BY revs.doc_id, revid DESC", selectArgs);
var lastDocID = 0L;
var keepGoing = cursor.MoveToNext();
while (keepGoing)
{
long docID = cursor.GetLong(0);
if (docID != lastDocID)
{
// Only look at the first-iterated revision of any document,
// because this is the
// one with the highest revid, hence the "winning" revision
// of a conflict.
lastDocID = docID;
// Reconstitute the document as a dictionary:
sequence = cursor.GetLong(1);
string docId = cursor.GetString(2);
if (docId.StartsWith("_design/", StringComparison.InvariantCultureIgnoreCase))
{
// design docs don't get indexed!
keepGoing = cursor.MoveToNext();
continue;
}
var revId = cursor.GetString(3);
var json = cursor.GetBlob(4);
var noAttachments = cursor.GetInt(5) > 0;
// Skip rows with the same doc_id -- these are losing conflicts.
while ((keepGoing = cursor.MoveToNext()) && cursor.GetLong(0) == docID)
{
}
if (lastSequence > 0)
{
// Find conflicts with documents from previous indexings.
var selectArgs2 = new[] { Convert.ToString(docID), Convert.ToString(lastSequence) };
cursor2 = Database.StorageEngine.IntransactionRawQuery("SELECT revid, sequence FROM revs "
+ "WHERE doc_id=? AND sequence<=? AND current!=0 AND deleted=0 " + "ORDER BY revID DESC "
+ "LIMIT 1", selectArgs2);
if (cursor2.MoveToNext())
{
var oldRevId = cursor2.GetString(0);
// This is the revision that used to be the 'winner'.
// Remove its emitted rows:
var oldSequence = cursor2.GetLong(1);
var args = new[] { Sharpen.Extensions.ToString(Id), Convert.ToString(oldSequence) };
Database.StorageEngine.ExecSQL("DELETE FROM maps WHERE view_id=? AND sequence=?", args);
if (RevisionInternal.CBLCompareRevIDs(oldRevId, revId) > 0)
{
// It still 'wins' the conflict, so it's the one that
// should be mapped [again], not the current revision!
revId = oldRevId;
sequence = oldSequence;
var selectArgs3 = new[] { Convert.ToString(sequence) };
json = Misc.ByteArrayResultForQuery(
Database.StorageEngine,
"SELECT json FROM revs WHERE sequence=?",
selectArgs3
);
}
}
cursor2.Close();
cursor2 = null;
}
// Get the document properties, to pass to the map function:
var contentOptions = DocumentContentOptions.None;
if (noAttachments)
{
contentOptions |= DocumentContentOptions.NoAttachments;
}
var properties = Database.DocumentPropertiesFromJSON(
json, docId, revId, false, sequence, DocumentContentOptions.None
);
if (properties != null)
{
// Call the user-defined map() to emit new key/value
// pairs from this revision:
// This is the emit() block, which gets called from within the
// user-defined map() block
// that's called down below.
var enclosingView = this;
var thisSequence = sequence;
var map = Map;
if (map == null)
{
throw new CouchbaseLiteException("Map function is missing.");
}
EmitDelegate emitBlock = (key, value) =>
{
// TODO: Do we need to do any null checks on key or value?
try
{
var keyJson = Manager.GetObjectMapper().WriteValueAsString(key);
var valueJson = value == null ? null : Manager.GetObjectMapper().WriteValueAsString(value);
var insertValues = new ContentValues();
insertValues.Put("view_id", enclosingView.Id);
insertValues["sequence"] = thisSequence;
insertValues["key"] = keyJson;
insertValues["value"] = valueJson;
enclosingView.Database.StorageEngine.Insert("maps", null, insertValues);
}
catch (Exception e)
{
Log.E(Database.Tag, "Error emitting", e);
}
};
map(properties, emitBlock);
}
}
else
{
keepGoing = cursor.MoveToNext();
}
}
// Finally, record the last revision sequence number that was
// indexed:
var updateValues = new ContentValues();
updateValues["lastSequence"] = dbMaxSequence;
var whereArgs_1 = new string[] { Id.ToString() };
Database.StorageEngine.Update("views", updateValues, "view_id=?", whereArgs_1);
// FIXME actually count number added :)
Log.V(Database.Tag, "...Finished re-indexing view {0} up to sequence {1} (deleted {2} added ?)", Name, Convert.ToString(dbMaxSequence), deleted);
result.SetCode(StatusCode.Ok);
return(true);
});
}
catch (Exception e)
{
throw new CouchbaseLiteException(e, new Status(StatusCode.DbError));
}
finally
{
if (cursor2 != null)
{
cursor2.Close();
}
if (cursor != null)
{
cursor.Close();
}
if (!result.IsSuccessful)
{
Log.W(Database.Tag, "Failed to rebuild view {0}:{1}", Name, result.GetCode());
}
}
}