public static BsonDocument Deserialize(byte[] bson, bool utcDate = true)
{
if (bson == null || bson.Length == 0)
{
throw new ArgumentNullException(nameof(bson));
}
return(BsonReader.Deserialize(bson, utcDate));
}
public static BsonDocument Deserialize(ArraySegment <byte> buffer, bool utcDate = true)
{
if (buffer == null || buffer.Count == 0)
{
throw new ArgumentNullException(nameof(buffer));
}
return(BsonReader.Deserialize(buffer, utcDate));
}
/// <summary>
/// Count all nodes from a query execution - do not deserialize documents to count. If query is null, use Collection counter variable
/// </summary>
public long Count(string collection, Query query = null)
{
if (collection.IsNullOrWhiteSpace())
{
throw new ArgumentNullException(nameof(collection));
}
var col = this.GetCollectionPage(collection, false);
if (col == null)
{
return(0);
}
if (query == null)
{
return(col.DocumentCount);
}
// run query in this collection
var nodes = query.Run(col, _indexer);
if (query.UseFilter)
{
// count distinct documents
return(nodes
.Select(x => BsonReader.Deserialize(_data.Read(x.DataBlock)).AsDocument)
.Where(x => query.FilterDocument(x))
.Distinct()
.LongCount());
}
else
{
// count distinct nodes based on DataBlock
return(nodes
.Select(x => x.DataBlock)
.Distinct()
.LongCount());
}
}
/// <summary>
/// Check if has at least one node in a query execution - do not deserialize documents to check
/// </summary>
public bool Exists(string collection, Query query)
{
if (collection.IsNullOrWhiteSpace())
{
throw new ArgumentNullException(nameof(collection));
}
if (query == null)
{
throw new ArgumentNullException(nameof(query));
}
var col = this.GetCollectionPage(collection, false);
if (col == null)
{
return(false);
}
// run query in this collection
var nodes = query.Run(col, _indexer);
if (query.UseFilter)
{
// check if has at least first document
return(nodes
.Select(x => BsonReader.Deserialize(_data.Read(x.DataBlock)).AsDocument)
.Where(x => query.FilterDocument(x))
.Any());
}
else
{
var first = nodes.FirstOrDefault();
// check if has at least first node
return(first != null);
}
}
/// <summary>
/// Implements delete based on a query result
/// </summary>
public int Delete(string collection, Query query)
{
if (collection.IsNullOrWhiteSpace())
{
throw new ArgumentNullException(nameof(collection));
}
if (query == null)
{
throw new ArgumentNullException(nameof(query));
}
return(this.Transaction <int>(collection, false, (col) =>
{
if (col == null)
{
return 0;
}
_log.Write(Logger.COMMAND, "delete documents in '{0}'", collection);
var nodes = query.Run(col, _indexer);
_log.Write(Logger.QUERY, "{0} :: {1}", collection, query);
var count = 0;
foreach (var node in nodes)
{
// checks if cache are full
_trans.CheckPoint();
// if use filter need deserialize document
if (query.UseFilter)
{
var buffer = _data.Read(node.DataBlock);
var doc = BsonReader.Deserialize(buffer).AsDocument;
if (query.FilterDocument(doc) == false)
{
continue;
}
}
_log.Write(Logger.COMMAND, "delete document :: _id = {0}", node.Key.RawValue);
// get all indexes nodes from this data block
var allNodes = _indexer.GetNodeList(node, true).ToArray();
// lets remove all indexes that point to this in dataBlock
foreach (var linkNode in allNodes)
{
var index = col.Indexes[linkNode.Slot];
_indexer.Delete(index, linkNode.Position);
}
// remove object data
_data.Delete(col, node.DataBlock);
count++;
}
return count;
}));
}
/// <summary>
/// Create a new index (or do nothing if already exists) to a collection/field
/// </summary>
public bool EnsureIndex(string collection, string field, bool unique = false)
{
if (collection.IsNullOrWhiteSpace())
{
throw new ArgumentNullException(nameof(collection));
}
if (!CollectionIndex.IndexPattern.IsMatch(field))
{
throw new ArgumentException("Invalid field format pattern: " + CollectionIndex.IndexPattern.ToString(), "field");
}
if (field == "_id")
{
return(false); // always exists
}
return(this.Transaction <bool>(collection, true, (col) =>
{
// check if index already exists
var current = col.GetIndex(field);
// if already exists, just exit
if (current != null)
{
// do not test any difference between current index and new defition
return false;
}
// create index head
var index = _indexer.CreateIndex(col);
index.Field = field;
index.Unique = unique;
_log.Write(Logger.COMMAND, "create index on '{0}' :: {1} unique: {2}", collection, index.Field, unique);
// read all objects (read from PK index)
foreach (var pkNode in new QueryAll("_id", Query.Ascending).Run(col, _indexer))
{
// read binary and deserialize document
var buffer = _data.Read(pkNode.DataBlock);
var doc = BsonReader.Deserialize(buffer).AsDocument;
var expr = new BsonFields(index.Field);
// get value from document
var keys = expr.Execute(doc, true);
// adding index node for each value
foreach (var key in keys)
{
// insert new index node
var node = _indexer.AddNode(index, key, pkNode);
// link index node to datablock
node.DataBlock = pkNode.DataBlock;
}
// check memory usage
_trans.CheckPoint();
}
return true;
}));
}
/// <summary>
/// Fetch documents from enumerator and add to buffer. If cache recycle, stop read to execute in another read
/// </summary>
public void Fetch(TransactionService trans, DataService data)
{
// empty document buffer
this.Documents.Clear();
// while until must cache not recycle
while (trans.CheckPoint() == false)
{
// read next node
this.HasMore = _nodes.MoveNext();
// if finish, exit loop
if (this.HasMore == false)
{
return;
}
// if run ONLY under index, skip/limit before deserialize
if (_query.UseIndex && _query.UseFilter == false)
{
if (--_skip >= 0)
{
continue;
}
if (--_limit <= -1)
{
this.HasMore = false;
return;
}
}
// get current node
var node = _nodes.Current;
// read document from data block
var buffer = data.Read(node.DataBlock);
var doc = BsonReader.Deserialize(buffer).AsDocument;
// if need run in full scan, execute full scan and test return
if (_query.UseFilter)
{
// execute query condition here - if false, do not add on final results
if (_query.FilterDocument(doc) == false)
{
continue;
}
// implement skip/limit after deserialize in full scan
if (--_skip >= 0)
{
continue;
}
if (--_limit <= -1)
{
this.HasMore = false;
return;
}
}
// increment position cursor
_position++;
// avoid lock again just to check limit
if (_limit == 0)
{
this.HasMore = false;
}
this.Documents.Add(doc);
}
}