public LiteCollection(string name, LazyLoad <LiteEngine> engine, BsonMapper mapper, Logger log)
{
_name = name ?? mapper.ResolveCollectionName(typeof(T));
_engine = engine;
_mapper = mapper;
_log = log;
_visitor = new QueryVisitor <T>(mapper);
_includes = new List <string>();
// if strong typed collection, get _id member mapped (if exists)
if (typeof(T) != typeof(BsonDocument))
{
var entity = mapper.GetEntityMapper(typeof(T));
_id = entity.Id;
if (_id != null && _id.AutoId)
{
_autoId =
_id.DataType == typeof(ObjectId) ? BsonType.ObjectId :
_id.DataType == typeof(Guid) ? BsonType.Guid :
_id.DataType == typeof(DateTime) ? BsonType.DateTime :
_id.DataType == typeof(Int32) ? BsonType.Int32 :
_id.DataType == typeof(Int64) ? BsonType.Int64 :
BsonType.Null;
}
}
else
{
_autoId = BsonType.ObjectId;
}
}
/// <summary>
/// Based on a LINQ expression, returns document field mapped from class Property.
/// Support multi level dotted notation: x => x.Customer.Name
/// Prefix is used on array expression like: x => x.Customers.Any(z => z.Name == "John")
/// </summary>
public string GetField(Expression expr, string prefix = "", bool showArrayItems = false)
{
var property = prefix + expr.GetPath();
var parts = property.Split('.');
var fields = new string[parts.Length];
var type = _type;
var isdbref = false;
// loop "first.second.last"
for (var i = 0; i < parts.Length; i++)
{
var entity = _mapper.GetEntityMapper(type);
var part = parts[i];
var prop = entity.Members.Find(x => x.MemberName == part);
if (prop == null)
{
throw new NotSupportedException(property + " not mapped in " + type.Name);
}
// if property is an IEnumerable, gets underlying type (otherwise, gets PropertyType)
type = prop.UnderlyingType;
fields[i] = prop.FieldName;
if (showArrayItems && prop.IsList)
{
fields[i] += "[*]";
}
if (prop.FieldName == "_id" && isdbref)
{
isdbref = false;
fields[i] = "$id";
}
// if this property is DbRef, so if next property is _id, change to $id
if (prop.IsDbRef)
{
isdbref = true;
}
}
return(string.Join(".", fields));
}
/// <summary>
/// Register a property as a DbRef - implement a custom Serialize/Deserialize actions to convert entity to $id, $ref only
/// </summary>
private static void RegisterDbRefItem(BsonMapper mapper, MemberMapper member, string collection)
{
// get entity
var entity = mapper.GetEntityMapper(member.DataType);
member.Serialize = (obj, m) =>
{
// supports null values when "SerializeNullValues = true"
if (obj == null)
{
return(BsonValue.Null);
}
var idField = entity.Id;
// #768 if using DbRef with interface with no ID mapped
if (idField == null)
{
throw new LiteException("There is no _id field mapped in your type: " + member.DataType.FullName);
}
var id = idField.Getter(obj);
return(new BsonDocument
{
{ "$id", m.Serialize(id.GetType(), id, 0) },
{ "$ref", collection }
});
};
member.Deserialize = (bson, m) =>
{
var idRef = bson.AsDocument["$id"];
return(m.Deserialize(entity.ForType,
idRef.IsNull ?
bson : // if has no $id object was full loaded (via Include) - so deserialize using normal function
new BsonDocument {
{ "_id", idRef }
})); // if has $id, deserialize object using only _id object
};
}
/// <summary>
/// Register a property as a DbRefList - implement a custom Serialize/Deserialize actions to convert entity to $id, $ref only
/// </summary>
private static void RegisterDbRefList(BsonMapper mapper, MemberMapper member, string collection)
{
// get entity from list item type
var entity = mapper.GetEntityMapper(member.UnderlyingType);
member.Serialize = (list, m) =>
{
// supports null values when "SerializeNullValues = true"
if (list == null)
{
return(BsonValue.Null);
}
var result = new BsonArray();
var idField = entity.Id;
foreach (var item in (IEnumerable)list)
{
if (item == null)
{
continue;
}
var id = idField.Getter(item);
result.Add(new BsonDocument
{
{ "$id", m.Serialize(id.GetType(), id, 0) },
{ "$ref", collection }
});
}
return(result);
};
member.Deserialize = (bson, m) =>
{
var array = bson.AsArray;
if (array.Count == 0)
{
return(m.Deserialize(member.DataType, array));
}
// copy array changing $id to _id
var result = new BsonArray();
foreach (var item in array)
{
var refId = item.AsDocument["$id"];
// if refId is null was included by "include" query, so "item" is full filled document
if (refId.IsNull)
{
result.Add(item);
}
else
{
result.Add(new BsonDocument {
{ "_id", refId }
});
}
}
return(m.Deserialize(member.DataType, result));
};
}
internal EntityBuilder(BsonMapper mapper)
{
_mapper = mapper;
_entity = mapper.GetEntityMapper(typeof(T));
}