public List <VertexField> GetVerticesByIds(HashSet <string> vertexId, GraphViewCommand command, string partition,
bool constructEdges = false)
{
const string NODE_ALIAS = "node";
var jsonQuery = new JsonQuery
{
NodeAlias = NODE_ALIAS,
RawWhereClause = new WBooleanComparisonExpression
{
ComparisonType = BooleanComparisonType.Equals,
FirstExpr = new WColumnReferenceExpression(NODE_ALIAS, DocumentDBKeywords.KW_EDGEDOC_IDENTIFIER),
SecondExpr = new WValueExpression("null")
}
};
// SELECT node
jsonQuery.AddSelectElement(NODE_ALIAS);
jsonQuery.FlatProperties.Add(DocumentDBKeywords.KW_EDGEDOC_IDENTIFIER);
jsonQuery.WhereConjunction(new WInPredicate(
new WColumnReferenceExpression(NODE_ALIAS, GremlinKeyword.NodeID),
vertexId.ToList()), BooleanBinaryExpressionType.And);
if (partition != null)
{
jsonQuery.WhereConjunction(new WBooleanComparisonExpression
{
ComparisonType = BooleanComparisonType.Equals,
FirstExpr = new WValueExpression($"{NODE_ALIAS}{command.Connection.GetPartitionPathIndexer()}", false),
SecondExpr = new WValueExpression(partition, true)
}, BooleanBinaryExpressionType.And);
}
jsonQuery.NodeProperties = new List <string> {
"node", "*"
};
jsonQuery.EdgeProperties = new List <string>();
IEnumerator <Tuple <VertexField, RawRecord> > queryResult = this.GetVerticesAndEdgesViaVertices(jsonQuery, command);
List <VertexField> result = new List <VertexField>();
while (queryResult.MoveNext())
{
VertexField vertex = queryResult.Current.Item1;
result.Add(vertex);
}
if (constructEdges)
{
// TODO: need double check on JsonServer
EdgeDocumentHelper.ConstructLazyAdjacencyList(command, EdgeType.Both, vertexId, new HashSet <string>());
}
return(result);
}
public IEnumerator <Tuple <VertexField, RawRecord> > GetVerticesAndEdgesViaVertices(JsonQuery vertexQuery,
GraphViewCommand command)
{
IEnumerable <JObject> items = this.ExecuteQueryScript(vertexQuery);
List <string> nodeProperties = new List <string>(vertexQuery.NodeProperties);
List <string> edgeProperties = new List <string>(vertexQuery.EdgeProperties);
string nodeAlias = nodeProperties[0];
// Skip i = 0, which is the (node.* as nodeAlias) field
nodeProperties.RemoveAt(0);
//
// TODO: Refactor
//
string edgeAlias = null;
bool isReverseAdj = false;
bool isStartVertexTheOriginVertex = false;
bool crossApplyEdgeOnServer = edgeProperties.Any();
if (crossApplyEdgeOnServer)
{
edgeAlias = edgeProperties[0];
isReverseAdj = bool.Parse(edgeProperties[1]);
isStartVertexTheOriginVertex = bool.Parse(edgeProperties[2]);
edgeProperties.RemoveAt(0);
edgeProperties.RemoveAt(0);
edgeProperties.RemoveAt(0);
}
//
// Batch strategy:
// - For "small" vertexes, they have been cross applied on the server side
// - For "large" vertexes, just return the VertexField, the adjacency list decoder will
// construct spilled adjacency lists in batch mode and cross apply edges after that
//
Func <VertexField, string, Tuple <VertexField, RawRecord> > makeCrossAppliedRecord = (vertexField, edgeId) => {
Debug.Assert(vertexField != null);
RawRecord nodeRecord = new RawRecord();
//
// Fill node property field
//
foreach (string propertyName in nodeProperties)
{
FieldObject propertyValue = vertexField[propertyName];
nodeRecord.Append(propertyValue);
}
RawRecord edgeRecord = new RawRecord(edgeProperties.Count);
EdgeField edgeField =
((AdjacencyListField)vertexField[isReverseAdj ? DocumentDBKeywords.KW_VERTEX_REV_EDGE : DocumentDBKeywords.KW_VERTEX_EDGE])
.GetEdgeField(edgeId, true);
string startVertexId = vertexField.VertexId;
AdjacencyListDecoder.FillMetaField(edgeRecord, edgeField, startVertexId, vertexField.Partition, isStartVertexTheOriginVertex, isReverseAdj);
AdjacencyListDecoder.FillPropertyField(edgeRecord, edgeField, edgeProperties);
nodeRecord.Append(edgeRecord);
return(new Tuple <VertexField, RawRecord>(vertexField, nodeRecord));
};
Func <VertexField, Tuple <VertexField, RawRecord> > makeRawRecord = (vertexField) => {
Debug.Assert(vertexField != null);
RawRecord rawRecord = new RawRecord();
//
// Fill node property field
//
foreach (string propertyName in nodeProperties)
{
FieldObject propertyValue = vertexField[propertyName];
rawRecord.Append(propertyValue);
}
return(new Tuple <VertexField, RawRecord>(vertexField, rawRecord));
};
HashSet <string> uniqueVertexIds = new HashSet <string>();
HashSet <string> uniqueEdgeIds = new HashSet <string>();
foreach (JObject dynamicItem in items)
{
JObject tmpVertexObject = (JObject)((JObject)dynamicItem)[nodeAlias];
string vertexId = (string)tmpVertexObject[DocumentDBKeywords.KW_DOC_ID];
if (crossApplyEdgeOnServer)
{
// Note: since vertex properties can be multi-valued,
// a DocumentDB query needs a join clause in the FROM clause
// to retrieve vertex property values, which may result in
// the same vertex being returned multiple times.
// We use the hash set uniqueVertexIds to ensure one vertex is
// produced only once.
if (EdgeDocumentHelper.IsBuildingTheAdjacencyListLazily(
tmpVertexObject,
isReverseAdj,
this.Connection.UseReverseEdges) &&
uniqueVertexIds.Add(vertexId))
{
VertexField vertexField = command.VertexCache.AddOrUpdateVertexField(vertexId, tmpVertexObject);
yield return(makeRawRecord(vertexField));
}
else // When the DocumentDB query crosses apply edges
{
JObject edgeObjct = (JObject)((JObject)dynamicItem)[edgeAlias];
string edgeId = (string)edgeObjct[DocumentDBKeywords.KW_EDGE_ID];
if (uniqueEdgeIds.Add(edgeId))
{
VertexField vertexField = command.VertexCache.AddOrUpdateVertexField(vertexId, tmpVertexObject);
yield return(makeCrossAppliedRecord(vertexField, edgeId));
}
}
}
else
{
if (!uniqueVertexIds.Add(vertexId))
{
continue;
}
VertexField vertexField = command.VertexCache.AddOrUpdateVertexField(vertexId, tmpVertexObject);
yield return(makeRawRecord(vertexField));
}
}
}