There are type annotations that uses Dict to annotate read-only mapping arguments, e.g. the conf argument here:
|
def __init__(self, conf: Dict[str, Union[str, int, float, bool]], **kwargs: Any) -> None: |
The problem is that Dict is invariant in its value type, meaning that in the example above where conf is typed as conf: Dict[str, Union[str, int, float, bool] it is not valid to assign a dict of type Dict[str, str].
That means code like this
from confluent_kafka.admin import AdminClient
conf = {
"bootstrap.servers": "kafka:9092"),
} # inferred type dict[str, str]
admin_client = AdminClient(conf)is rejected by type-checkers.
The solution here would be to annotate conf with collections.abc.Mapping instead of Dict, as Mapping is covariant in its value-type.
There are type annotations that uses Dict to annotate read-only mapping arguments, e.g. the
confargument here:confluent-kafka-python/src/confluent_kafka/admin/__init__.py
Line 118 in 7d0abd5
The problem is that Dict is invariant in its value type, meaning that in the example above where conf is typed as
conf: Dict[str, Union[str, int, float, bool]it is not valid to assign a dict of typeDict[str, str].That means code like this
is rejected by type-checkers.
The solution here would be to annotate
confwithcollections.abc.Mappinginstead of Dict, asMappingis covariant in its value-type.