// build a query for the separate hashes-table, or the document hash array that ignores
// the actual index of the hashbin
private LiteDB.BsonExpression GetQueryForHashBinsIgnoreIndex(int[] hashBins, bool useSeparateTable)
{
// don't care about the actual index of the hasbin, only if it exists
// See https://github.com/perivar/FindSimilar2/blob/master/Soundfingerprinting/DatabaseService.cs\
var bsonArray = new LiteDB.BsonArray(hashBins.Select(x => new BsonValue(x)));
if (useSeparateTable)
{
return(LiteDB.Query.In("HashBin", bsonArray));
}
else
{
// use the hashbin array on the main document
return(LiteDB.Query.In("HashBins[*]", bsonArray));
}
}
public List <TrackData> ReadTracksByReferences(IEnumerable <IModelReference> ids)
{
// get track collection
var col = db.GetCollection <TrackDataDTO>("tracks");
// two alternative methods
// 1. use Query.In
var bsonArray = new LiteDB.BsonArray(ids.Select(x => new BsonValue(x.Id)));
var results = col.Find(LiteDB.Query.In("_id", bsonArray));
// 2. Use Find and Linq Contains
// var results = col.Find(x => ids.Contains(new ModelReference<string>(x.Id)));
if (results.Count() == 0)
{
return(new List <TrackData>());
}
return(results.Select(TrackDataDTO.CopyToTrackData).ToList());
}
public List <SubFingerprintData> ReadSubFingerprintDataByReference(IEnumerable <IModelReference> ids)
{
// Get fingerprint collection
var col = db.GetCollection <SubFingerprintDTO>("fingerprints");
// ensure indexes
col.EnsureIndex(x => x.SubFingerprintId);
// two alternative methods
// 1. use Query.In
var bsonArray = new LiteDB.BsonArray(ids.Select(x => new BsonValue(x.Id)));
var results = col.Find(LiteDB.Query.In("_id", bsonArray));
// 2. Use Find and Linq Contains
// var results = col.Find(x => ids.Contains(new ModelReference<string>(x.Id)));
if (results.Count() == 0)
{
return(new List <SubFingerprintData>());
}
return(results.Select(SubFingerprintDTO.CopyToSubFingerprintData).ToList());
}
/// <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) =>
{
if (bson.IsArray == false)
{
return(null);
}
var array = bson.AsArray;
if (array.Count == 0)
{
return(m.Deserialize(member.DataType, array));
}
// copy array changing $id to _id
var result = new BsonArray();
foreach (var item in array)
{
var refId = item["$id"];
var missing = item["$missing"] == true;
// if referece document are missing, do not inlcude on output list
if (missing)
{
continue;
}
// 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));
};
}
/// <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) },
{ "$ref", collection }
});
}
return(result);
};
member.Deserialize = (bson, m) =>
{
var array = bson.AsArray;
if (array.Count == 0)
{
return(m.Deserialize(member.DataType, array));
}
var hasIdRef = array[0].AsDocument == null || array[0].AsDocument["$id"].IsNull;
if (hasIdRef)
{
// if no $id, deserialize as full (was loaded via Include)
return(m.Deserialize(member.DataType, array));
}
else
{
// copy array changing $id to _id
var arr = new BsonArray();
foreach (var item in array)
{
arr.Add(new BsonDocument {
{ "_id", item.AsDocument["$id"] }
});
}
return(m.Deserialize(member.DataType, arr));
}
};
}
