public async Task <T> GetDocumentWithSpecificFieldsAsync(string objectIdString, string[] projectionFields)
{
// TODO:Mohit Use FilterDefinitionBuilder - as the class is created for specific purpose
var filter = new BsonDocument();
filter.Add("_id", objectIdString);
var projBuilder = new ProjectionDefinitionBuilder <T>();
ProjectionDefinition <T>[] projections = new ProjectionDefinition <T> [projectionFields.Length];
for (int i = 0; i < projectionFields.Length; i++)
{
var prof = projBuilder.Include(projectionFields[i]);
projections[i] = prof;
}
var projectionDefinition = projBuilder.Combine(projections);
var resultList = await this.Collection.Find(filter).Project <T>(projectionDefinition).ToListAsync();
//var resultList = await collection.Find(filter).ToListAsync();
if (resultList.Count > 0)
{
return(resultList[0]);
}
else
{
return(null);
}
}
public static ProjectionDefinition <TDocument> CreateMongoProjection(Action <IDocumentProjectionBuilder> projection)
{
var builder = new MongoDocumentProjectionBuilder <TDocument>();
projection?.Invoke(builder);
return((builder._projections.Count != 1) ? InternalBuilder.Combine(builder._projections) : builder._projections[0]);
}
protected virtual ProjectionDefinition <T> CreateProjectionDefinition(
ProjectionParams projection, ProjectionDefinitionBuilder <T> projectionBuilder)
{
projection = projection ?? new ProjectionParams();
return(projectionBuilder.Combine(
projection.Select(field => projectionBuilder.Include(field))
).Exclude(InternalIdFieldName));
}
private BsonDocument simpleKeyQuery()
{
// Key Query
rotateCollection();
BsonDocument query = new BsonDocument();
int range = sequence * testOpts.workingset / 100;
int rest = sequence - range;
int recordno = rest + getNextVal(range);
query.Add("_id",
new BsonDocument("w", workerID).Add("i", recordno));
DateTime starttime = DateTime.Now;
BsonDocument myDoc;
List <String> projFields = new List <String>(testOpts.numFields);
if (testOpts.projectFields == 0)
{
myDoc = coll.Find(query).FirstOrDefault();
}
else
{
int numProjFields = (testOpts.projectFields <= testOpts.numFields) ? testOpts.projectFields : testOpts.numFields;
int i = 0;
while (i < numProjFields)
{
projFields.Add("fld" + i);
i++;
}
var projection = new ProjectionDefinitionBuilder <BsonDocument>();
foreach (var field in projFields)
{
projection.Include(field);
}
myDoc = coll.Find(query)
.Project <BsonDocument>(projection.Combine())
.FirstOrDefault();
}
if (myDoc != null)
{
var taken = (DateTime.Now - starttime).TotalMilliseconds;
if (taken > testOpts.slowThreshold)
{
testResults.RecordSlowOp("keyqueries", 1);
}
testResults.RecordOpsDone("keyqueries", 1);
}
return(myDoc);
}
private void rangeQuery()
{
// Key Query
rotateCollection();
BsonDocument query = new BsonDocument();
var projection = new ProjectionDefinitionBuilder <BsonDocument>();
int recordno = getNextVal(sequence);
query.Add("_id", new BsonDocument("$gt", new BsonDocument("w",
workerID).Add("i", recordno)));
DateTime starttime = new DateTime();
IAsyncCursor <BsonDocument> cursor;
if (testOpts.projectFields == 0)
{
cursor = coll.Find(query)
.Limit(testOpts.rangeDocs)
.ToCursor();
}
else
{
int numProjFields = (testOpts.projectFields <= testOpts.numFields) ? testOpts.projectFields : testOpts.numFields;
for (int i = 0; i < numProjFields; i++)
{
projection.Include("fld" + i);
}
cursor = coll.Find(query)
.Project <BsonDocument>(projection.Combine())
.Limit(testOpts.rangeDocs)
.ToCursor();
}
while (cursor.MoveNext())
{
var batch = cursor.Current;
foreach (var doc in batch)
{
// Consume the cursor
}
}
cursor.Dispose();
var taken = (DateTime.Now - starttime).TotalMilliseconds;
if (taken > testOpts.slowThreshold)
{
testResults.RecordSlowOp("rangequeries", 1);
}
testResults.RecordOpsDone("rangequeries", 1);
}
public async Task <List <T> > GetAllDocumentsWithSpecificFieldsAsync(string[] projectionFields)
{
var filter = new BsonDocument();
var projBuilder = new ProjectionDefinitionBuilder <T>();
ProjectionDefinition <T>[] projections = new ProjectionDefinition <T> [projectionFields.Length];
for (int i = 0; i < projectionFields.Length; i++)
{
var prof = projBuilder.Include(projectionFields[i]);
projections[i] = prof;
}
var projectionDefinition = projBuilder.Combine(projections);
var result = await this.Collection.Find(filter).Project <T>(projectionDefinition).ToListAsync();
return(result);
}
/// <summary>
/// 获取字段
/// </summary>
/// <param name="fieldsExp"></param>
/// <returns></returns>
public ProjectionDefinition <T> IncludeFields <T>(Expression <Func <T, object> > fieldsExp) where T : class, new()
{
ProjectionDefinitionBuilder <T> projection = Builders <T> .Projection;
if (fieldsExp == null)
{
return(null);
}
List <ProjectionDefinition <T> > list = new List <ProjectionDefinition <T> >();
NewExpression newExpression = fieldsExp.Body as NewExpression;
if (newExpression == null || newExpression.Members == null)
{
throw new Exception("fieldsExp is invalid expression format， eg: x => new { x.Field1, x.Field2 }");
}
foreach (MemberInfo current in newExpression.Members)
{
list.Add(projection.Include(current.Name));
}
return(projection.Combine(list));
}
