public Action <MappingSchema, NpgsqlBinaryImporter, ColumnDescriptor[], TEntity> CreateBinaryImportRowWriter <TEntity>(
PostgreSQLDataProvider provider,
BasicSqlBuilder sqlBuilder,
ColumnDescriptor[] columns,
MappingSchema mappingSchema)
{
var generator = new ExpressionGenerator(_typeMapper);
var pMapping = Expression.Parameter(typeof(MappingSchema));
var pWriterIn = Expression.Parameter(typeof(NpgsqlBinaryImporter));
var pColumns = Expression.Parameter(typeof(ColumnDescriptor[]));
var pEntity = Expression.Parameter(typeof(TEntity));
var pWriter = generator.AddVariable(Expression.Parameter(_npgsqlBinaryImporterType));
generator.Assign(pWriter, Expression.Convert(ExpressionHelper.Property(pWriterIn, nameof(TypeWrapper.instance_)), _npgsqlBinaryImporterType));
generator.AddExpression(generator.MapAction((NpgsqlBinaryImporter importer) => importer.StartRow(), pWriter));
for (var i = 0; i < columns.Length; i++)
{
var npgsqlType = provider.GetNativeType(columns[i].DbType, true);
if (npgsqlType == null)
{
var columnType = columns[i].DataType != DataType.Undefined ? new SqlDataType(columns[i]) : null;
if (columnType == null || columnType.Type.DataType == DataType.Undefined)
{
columnType = mappingSchema.GetDataType(columns[i].StorageType);
}
var sb = new StringBuilder();
sqlBuilder.BuildTypeName(sb, columnType);
npgsqlType = provider.GetNativeType(sb.ToString(), true);
}
if (npgsqlType == null)
{
throw new LinqToDBException($"Cannot guess PostgreSQL type for column {columns[i].ColumnName}. Specify type explicitly in column mapping.");
}
// don't use WriteNull because Write already handle both null and DBNull values properly
// also use object as type parameter, as it is not important for npgsql now
generator.AddExpression(
Expression.Call(
pWriter,
"Write",
new[] { typeof(object) },
//columns[idx].GetValue(mappingSchema, entity)
Expression.Call(Expression.ArrayIndex(pColumns, Expression.Constant(i)), "GetValue", Array <Type> .Empty, pMapping, pEntity),
Expression.Convert(Expression.Constant(npgsqlType.Value), _dbTypeType)));
}
var ex = Expression.Lambda <Action <MappingSchema, NpgsqlBinaryImporter, ColumnDescriptor[], TEntity> >(
generator.Build(),
pMapping, pWriterIn, pColumns, pEntity);
return(ex.Compile());
}
public void Setup()
{
var typeMapper = new TypeMapper();
typeMapper.RegisterTypeWrapper <Wrapped.NpgsqlBinaryImporter>(typeof(Original.NpgsqlBinaryImporter));
typeMapper.RegisterTypeWrapper <Wrapped.NpgsqlDbType>(typeof(Original.NpgsqlDbType));
typeMapper.FinalizeMappings();
_wrappedImporter = typeMapper.Wrap <Wrapped.NpgsqlBinaryImporter>(_originalImporter);
var ed = MappingSchema.GetEntityDescriptor(typeof(TestEntity));
_columns = ed.Columns.ToArray();
var generator = new ExpressionGenerator(typeMapper);
var pMapping = Expression.Parameter(typeof(MappingSchema));
var pWriterIn = Expression.Parameter(typeof(Wrapped.NpgsqlBinaryImporter));
var pColumns = Expression.Parameter(typeof(ColumnDescriptor[]));
var pEntity = Expression.Parameter(typeof(TestEntity));
var pWriter = generator.AddVariable(Expression.Parameter(typeof(Original.NpgsqlBinaryImporter)));
generator.Assign(pWriter, Expression.Convert(Expression.PropertyOrField(pWriterIn, "instance_"), typeof(Original.NpgsqlBinaryImporter)));
generator.AddExpression(generator.MapAction((Wrapped.NpgsqlBinaryImporter importer) => importer.StartRow(), pWriter));
for (var i = 0; i < _columns.Length; i++)
{
generator.AddExpression(
Expression.Call(
pWriter,
"Write",
new[] { typeof(object) },
Expression.Call(Expression.ArrayIndex(pColumns, Expression.Constant(i)), "GetValue", Array <Type> .Empty, pEntity),
Expression.Convert(Expression.Constant(Wrapped.NpgsqlDbType.Test), typeof(Original.NpgsqlDbType))));
}
_rowWriter = Expression.Lambda <Action <MappingSchema, Wrapped.NpgsqlBinaryImporter, ColumnDescriptor[], TestEntity> >(
generator.Build(),
pMapping, pWriterIn, pColumns, pEntity)
.Compile();
}
