A TypeORM object which knows the DataSource it belongs to, such as a QueryBuilder,
EntityManager, QueryRunner or EntityMetadata. TypeORM 0.3 names that property .
TypeORM 1 renames it to and keeps as a deprecated alias on some,
but not all, of those classes. Code which has to run on both versions therefore reads the
DataSource via rather than naming either property directly.
connectiondataSourceconnection