Dynamodb client query behaves differently depending on whether it is a new client or it comes from the resource

I have a parameters variable

params = {
        "TableName": "name_of_table",
        "KeyConditionExpression": "user_id = :user_id",
        "ExpressionAttributeValues": {
            ":user_id": { "S": "username" }
        },
    }

I also created a client

client = boto3.client("dynamodb") and ran

client.query(**params) which returns the correct data from our table. But when we create a resource

resource = boto3.resource("dynamodb")

and run

resource.meta.client.query(**params)

I get the error

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python3.7/site-packages/botocore/client.py", line 357, in _api_call
    return self._make_api_call(operation_name, kwargs)
  File "/usr/local/lib/python3.7/site-packages/botocore/client.py", line 661, in _make_api_call
    raise error_class(parsed_response, operation_name)
botocore.exceptions.ClientError: An error occurred (ValidationException) when calling the Query operation: One or more parameter values were invalid: Condition parameter type does not match schema type

[jg75]

It looks like client.query requires the attribute values to be in the encoded format, i.e. ":user_id": { "S": "username" } but the resource.meta.client.query requires it to be uncoded, i.e. ":user_id": "username" EDIT: The documentation leads me to believe that it should be encoded in both cases

[JeremieRodon]

I think you missed his point. I believe it is fair to expect that boto3.client('dynamodb') and boto3.resource('dynamodb').meta.client should behave the same way and his example demonstrate that it is not the case.