public bool UpdateIndexes(IEnumerable <IViewStore> inputViews)
{
Log.To.View.I(Tag, "Checking indexes of ({0}) for {1}", ViewNames(inputViews.Cast <SqliteViewStore>()), Name);
var db = _dbStorage;
var status = false;
status = db.RunInTransaction(() =>
{
long dbMaxSequence = db.LastSequence;
long forViewLastSequence = LastSequenceIndexed;
// Check whether we need to update at all,
// and remove obsolete emitted results from the 'maps' table:
long minLastSequence = dbMaxSequence;
long[] viewLastSequence = new long[inputViews.Count()];
int deletedCount = 0;
int i = 0;
HashSet <string> docTypes = new HashSet <string>();
IDictionary <string, string> viewDocTypes = null;
bool allDocTypes = false;
IDictionary <int, int> viewTotalRows = new Dictionary <int, int>();
List <SqliteViewStore> views = new List <SqliteViewStore>(inputViews.Count());
List <MapDelegate> mapBlocks = new List <MapDelegate>();
foreach (var view in inputViews.Cast <SqliteViewStore>())
{
var viewDelegate = view.Delegate;
var mapBlock = viewDelegate == null ? null : viewDelegate.Map;
if (mapBlock == null)
{
Debug.Assert(view != this, String.Format("Cannot index view {0}: no map block registered", view.Name));
Log.To.View.V(Tag, " {0} has no map block; skipping it", view.Name);
continue;
}
long last = view == this ? forViewLastSequence : view.LastSequenceIndexed;
if (last >= dbMaxSequence)
{
Log.To.View.V(Tag, "{0} is already up to date, skipping...", view.Name);
continue;
}
views.Add(view);
mapBlocks.Add(mapBlock);
int viewId = view.ViewID;
Debug.Assert(viewId > 0, String.Format("View '{0}' not found in database", view.Name));
int totalRows = view.TotalRows;
viewTotalRows[viewId] = totalRows;
viewLastSequence[i++] = last;
if (last < 0)
{
throw Misc.CreateExceptionAndLog(Log.To.View, StatusCode.DbError, Tag,
"Invalid last sequence indexed ({0}) received from {1}", last, view);
}
if (last < dbMaxSequence)
{
if (last == 0)
{
CreateIndex();
}
minLastSequence = Math.Min(minLastSequence, last);
Log.To.View.V(Tag, " {0} last indexed at #{1}", view.Name, last);
string docType = viewDelegate.DocumentType;
if (docType != null)
{
docTypes.Add(docType);
if (viewDocTypes == null)
{
viewDocTypes = new Dictionary <string, string>();
}
viewDocTypes[view.Name] = docType;
}
else
{
// can't filter by doc_type
allDocTypes = true;
}
bool ok = true;
int changes = 0;
if (last == 0)
{
try {
// If the lastSequence has been reset to 0, make sure to remove all map results:
using (var changesCursor = db.StorageEngine.RawQuery(view.QueryString("SELECT COUNT(*) FROM maps_#"))) {
changes = changesCursor.GetInt(0);
}
DeleteIndex();
CreateIndex();
} catch (Exception) {
ok = false;
}
}
else
{
db.OptimizeSQLIndexes(); // ensures query will use the right indexes
// Delete all obsolete map results (ones from since-replaced revisions):
try {
changes = db.StorageEngine.ExecSQL(view.QueryString("DELETE FROM 'maps_#' WHERE sequence IN (" +
"SELECT parent FROM revs WHERE sequence>?" +
"AND +parent>0 AND +parent<=?)"), last, last);
} catch (Exception) {
ok = false;
}
}
if (!ok)
{
throw Misc.CreateExceptionAndLog(Log.To.View, StatusCode.DbError, Tag,
"Error deleting obsolete map results before index update");
}
// Update #deleted rows
deletedCount += changes;
// Only count these deletes as changes if this isn't a view reset to 0
if (last != 0)
{
viewTotalRows[viewId] -= changes;
}
}
}
if (minLastSequence == dbMaxSequence)
{
return(true);
}
Log.To.View.I(Tag, "Updating indexes of ({0}) from #{1} to #{2} ...",
ViewNames(views), minLastSequence, dbMaxSequence);
// This is the emit() block, which gets called from within the user-defined map() block
// that's called down below.
SqliteViewStore currentView = null;
IDictionary <string, object> currentDoc = null;
long sequence = minLastSequence;
Status emitStatus = new Status(StatusCode.Ok);
int insertedCount = 0;
EmitDelegate emit = (key, value) =>
{
if (key == null)
{
Log.To.View.W(Tag, "Emit function called with a null key; ignoring");
return;
}
StatusCode s = currentView.Emit(key, value, value == currentDoc, sequence);
if (s != StatusCode.Ok)
{
emitStatus.Code = s;
}
else
{
viewTotalRows[currentView.ViewID] += 1;
insertedCount++;
}
};
// Now scan every revision added since the last time the views were indexed:
bool checkDocTypes = docTypes.Count > 1 || (allDocTypes && docTypes.Count > 0);
var sql = new StringBuilder("SELECT revs.doc_id, sequence, docid, revid, json, deleted ");
if (checkDocTypes)
{
sql.Append(", doc_type ");
}
sql.Append("FROM revs, docs WHERE sequence>? AND sequence <=? AND current!=0 ");
if (minLastSequence == 0)
{
sql.Append("AND deleted=0 ");
}
if (!allDocTypes && docTypes.Count > 0)
{
sql.AppendFormat("AND doc_type IN ({0}) ", Utility.JoinQuoted(docTypes));
}
sql.Append("AND revs.doc_id = docs.doc_id " +
"ORDER BY revs.doc_id, deleted, revid DESC");
Cursor c = null;
Cursor c2 = null;
try {
c = db.StorageEngine.IntransactionRawQuery(sql.ToString(), minLastSequence, dbMaxSequence);
bool keepGoing = c.MoveToNext();
while (keepGoing)
{
// Get row values now, before the code below advances 'c':
long doc_id = c.GetLong(0);
sequence = c.GetLong(1);
string docId = c.GetString(2);
if (docId.StartsWith("_design/")) // design documents don't get indexed
{
keepGoing = c.MoveToNext();
continue;
}
string revId = c.GetString(3);
var json = c.GetBlob(4);
bool deleted = c.GetInt(5) != 0;
string docType = checkDocTypes ? c.GetString(6) : null;
// Skip rows with the same doc_id -- these are losing conflicts.
var conflicts = default(List <string>);
while ((keepGoing = c.MoveToNext()) && c.GetLong(0) == doc_id)
{
if (conflicts == null)
{
conflicts = new List <string>();
}
conflicts.Add(c.GetString(3));
}
long realSequence = sequence; // because sequence may be changed, below
if (minLastSequence > 0)
{
// Find conflicts with documents from previous indexings.
using (c2 = db.StorageEngine.IntransactionRawQuery("SELECT revid, sequence FROM revs " +
"WHERE doc_id=? AND sequence<=? AND current!=0 AND deleted=0 " +
"ORDER BY revID DESC ", doc_id, minLastSequence)) {
if (c2.MoveToNext())
{
string oldRevId = c2.GetString(0);
// This is the revision that used to be the 'winner'.
// Remove its emitted rows:
long oldSequence = c2.GetLong(1);
foreach (var view in views)
{
int changes = db.StorageEngine.ExecSQL(QueryString("DELETE FROM 'maps_#' WHERE sequence=?"), oldSequence);
deletedCount += changes;
viewTotalRows[view.ViewID] -= changes;
}
if (deleted || RevisionID.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;
deleted = false;
sequence = oldSequence;
json = db.QueryOrDefault <byte[]>(x => x.GetBlob(0), true, null, "SELECT json FROM revs WHERE sequence=?", sequence);
}
if (!deleted)
{
// Conflict revisions:
if (conflicts == null)
{
conflicts = new List <string>();
}
conflicts.Add(oldRevId);
while (c2.MoveToNext())
{
conflicts.Add(c2.GetString(0));
}
}
}
}
}
if (deleted)
{
continue;
}
// Get the document properties, to pass to the map function:
currentDoc = db.GetDocumentProperties(json, docId, revId, deleted, sequence);
if (currentDoc == null)
{
Log.To.View.W(Tag, "Failed to parse JSON of doc {0} rev {1}, skipping...",
new SecureLogString(docId, LogMessageSensitivity.PotentiallyInsecure), revId);
continue;
}
currentDoc["_local_seq"] = sequence;
if (conflicts != null)
{
currentDoc["_conflicts"] = conflicts;
}
// Call the user-defined map() to emit new key/value pairs from this revision:
int viewIndex = -1;
var e = views.GetEnumerator();
while (e.MoveNext())
{
currentView = e.Current;
++viewIndex;
if (viewLastSequence[viewIndex] < realSequence)
{
if (checkDocTypes)
{
var viewDocType = viewDocTypes[currentView.Name];
if (viewDocType != null && viewDocType != docType)
{
// skip; view's documentType doesn't match this doc
continue;
}
}
Log.To.View.V(Tag, " #{0}: map \"{1}\" for view {2}...",
sequence, docId, e.Current.Name);
try {
mapBlocks[viewIndex](currentDoc, emit);
} catch (Exception x) {
Log.To.View.E(Tag, String.Format("Exception in map() block for view {0}, cancelling update...", currentView.Name), x);
emitStatus.Code = StatusCode.Exception;
}
if (emitStatus.IsError)
{
c.Dispose();
return(false);
}
}
}
currentView = null;
}
} catch (CouchbaseLiteException) {
Log.To.View.E(Tag, "Failed to update index for {0}, rethrowing...", currentView.Name);
throw;
} catch (Exception e) {
throw Misc.CreateExceptionAndLog(Log.To.View, e, Tag, "Error updating index for {0}", currentView.Name);
} finally {
if (c != null)
{
c.Dispose();
}
}
// Finally, record the last revision sequence number that was indexed and update #rows:
foreach (var view in views)
{
view.FinishCreatingIndex();
int newTotalRows = viewTotalRows[view.ViewID];
Debug.Assert(newTotalRows >= 0);
var args = new ContentValues();
args["lastSequence"] = dbMaxSequence;
args["total_docs"] = newTotalRows;
try {
db.StorageEngine.Update("views", args, "view_id=?", view.ViewID.ToString());
} catch (CouchbaseLiteException) {
Log.To.View.E(Tag, "Failed to update view {0}, rethrowing...", view.Name);
throw;
} catch (Exception e) {
throw Misc.CreateExceptionAndLog(Log.To.View, e, Tag, "Error updating view {0}", view.Name);
}
}
Log.To.View.I(Tag, "...Finished re-indexing ({0}) to #{1} (deleted {2}, added {3})",
ViewNames(views), dbMaxSequence, deletedCount, insertedCount);
return(true);
});
if (!status)
{
Log.To.View.W(Tag, "Failed to rebuild views ({0}): {1}", ViewNames(inputViews.Cast <SqliteViewStore>()), status);
}
return(status);
}
private bool RevIdGreaterThanCurrent(string revId)
{
return(RevisionID.CBLCompareRevIDs(revId, currentRevision.Id) > 0);
}