public QueryVisitor(BsonMapper mapper)
{
_mapper = mapper;
_type = typeof(T);
}
/// <summary>
/// Starts LiteDB database using a connection string for file system database
/// </summary>
public LiteDatabase(string connectionString, BsonMapper mapper = null, Logger log = null)
: this(new ConnectionString(connectionString), mapper, log)
{
}
/// <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));
};
}