internal async Task <List <Document> > GetNextSetHelperAsync(CancellationToken cancellationToken)
{
List <Document> ret = new List <Document>();
if (!IsDone)
{
switch (SearchMethod)
{
case SearchType.Scan:
ScanRequest scanReq = new ScanRequest
{
ExclusiveStartKey = NextKey,
Limit = Limit,
TableName = TableName,
AttributesToGet = AttributesToGet,
ScanFilter = Filter.ToConditions(SourceTable),
Select = EnumMapper.Convert(Select),
ConsistentRead = IsConsistentRead
};
if (!string.IsNullOrEmpty(this.IndexName))
{
scanReq.IndexName = this.IndexName;
}
if (this.FilterExpression != null && this.FilterExpression.IsSet)
{
this.FilterExpression.ApplyExpression(scanReq, SourceTable);
}
if (scanReq.ScanFilter != null && scanReq.ScanFilter.Count > 1)
{
scanReq.ConditionalOperator = EnumMapper.Convert(ConditionalOperator);
}
Common.ConvertAttributesToGetToProjectionExpression(scanReq);
if (this.TotalSegments != 0)
{
scanReq.TotalSegments = this.TotalSegments;
scanReq.Segment = this.Segment;
}
SourceTable.AddRequestHandler(scanReq, isAsync: true);
var scanResult = await SourceTable.DDBClient.ScanAsync(scanReq, cancellationToken).ConfigureAwait(false);
foreach (var item in scanResult.Items)
{
Document doc = SourceTable.FromAttributeMap(item);
ret.Add(doc);
if (CollectResults)
{
Matches.Add(doc);
}
}
NextKey = scanResult.LastEvaluatedKey;
if (NextKey == null || NextKey.Count == 0)
{
IsDone = true;
}
return(ret);
case SearchType.Query:
QueryRequest queryReq = new QueryRequest
{
TableName = TableName,
ConsistentRead = IsConsistentRead,
Select = EnumMapper.Convert(Select),
ExclusiveStartKey = NextKey,
Limit = Limit,
ScanIndexForward = !IsBackwardSearch,
AttributesToGet = AttributesToGet,
IndexName = IndexName,
};
Expression.ApplyExpression(queryReq, SourceTable, KeyExpression, FilterExpression);
Dictionary <string, Condition> keyConditions, filterConditions;
SplitQueryFilter(Filter, SourceTable, queryReq.IndexName, out keyConditions, out filterConditions);
queryReq.KeyConditions = keyConditions;
queryReq.QueryFilter = filterConditions;
Common.ConvertAttributesToGetToProjectionExpression(queryReq);
if (queryReq.QueryFilter != null && queryReq.QueryFilter.Count > 1)
{
queryReq.ConditionalOperator = EnumMapper.Convert(ConditionalOperator);
}
SourceTable.AddRequestHandler(queryReq, isAsync: true);
var queryResult = await SourceTable.DDBClient.QueryAsync(queryReq, cancellationToken).ConfigureAwait(false);
foreach (var item in queryResult.Items)
{
Document doc = SourceTable.FromAttributeMap(item);
ret.Add(doc);
if (CollectResults)
{
Matches.Add(doc);
}
}
NextKey = queryResult.LastEvaluatedKey;
if (NextKey == null || NextKey.Count == 0)
{
IsDone = true;
}
return(ret);
default:
throw new InvalidOperationException("Unknown Search Method");
}
}
return(ret);
}
