René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Misleading error message when user is missing permissions","articleBody":"#### Environment details\r\n\r\n  - OS type and version: MacOS 11.6.2\r\n  - Python version: 3.9.9\r\n  - pip version: 20.3.4\r\n  - `pandas-gbq` version: 0.17.0\r\n\r\n#### Steps to reproduce\r\n\r\n1. Create a service account that has the \"BigQuery Data Editor\" and \"BigQuery JobUser\" roles (these are not sufficient for using read_gbq; it's a user error to use them, but the focus of this ticket is that the helpful error message gets lost):\r\n2. Invoke pandas_gbq.read_gbq with params that should work - i.e. they'd work fine if the user had the \"BigQuery User\" role\r\n\r\nYou'll get this error:\r\n\r\n```\r\n\u003e       if isinstance(rpc_exc, grpc.Call) or _is_informative_grpc_error(rpc_exc):\r\nE       AttributeError: 'NoneType' object has no attribute 'Call'\r\n```\r\n\r\nThe actual error is visible in the traceback:\r\n\r\n```\r\nE           grpc._channel._InactiveRpcError: \u003c_InactiveRpcError of RPC that terminated with:\r\nE           \tstatus = StatusCode.PERMISSION_DENIED\r\nE           \tdetails = \"request failed: the user does not have 'bigquery.readsessions.create' permission for 'projects/redacted'\"\r\n```\r\n\r\nThe \"NoneType has no attribute\" message is misleading and obscures the problem. I believe the error should be reporting the permission issue that is captured in the above block.\r\n\r\nAgain, this is ultimately a user error due to the wrong permissions being used, but a user will find that out more quickly by getting back the actual error instead of the \"NoneType has no attribute\" error. ","author":{"url":"https://github.com/rjrudin","@type":"Person","name":"rjrudin"},"datePublished":"2022-02-17T18:34:33.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":4},"url":"https://github.com/342/python-api-core/issues/342"}