Just starting to use

dagster

. I’ve tried to use a Resource in my Asset, but I’m stuck with a

dagster._core.errors.DagsterInvalidDefinitionError: Invalid type: dagster_type must be an instance of DagsterType or a Python type: got GoogleDriveClient.

error. Here’s my minimal working example:

from dagster import asset, ConfigurableResource, Definitions
from googleapiclient.discovery import build

class GoogleDriveClient(ConfigurableResource):
    def get_folder(self, name: str) -> str:
        query = f"mimeType='application/vnd.google-apps.folder' and trashed=false and name='{name}'"
        response = build("drive", "v3").files().list(q=query).execute()
        return response.get("files", [])[0].get("id", "")

@asset
def get_folder(gdrive: GoogleDriveClient) -> str:
    return gdrive.get_folder("My Folder")

defs = Definitions(assets=[get_folder], resources={"gdrive": GoogleDriveClient()})

Here’s what I would like to work:

from __future__ import annotations
from typing import TYPE_CHECKING
from dagster import asset, ConfigurableResource, Definitions
from googleapiclient.discovery import build

if TYPE_CHECKING:
    from googleapiclient._apis.drive.v3.schemas import File

class GoogleDriveClient(ConfigurableResource):
    def get_folder(self, name: str) -> File:
        query = f"mimeType='application/vnd.google-apps.folder' and trashed=false and name='{name}'"
        response = build("drive", "v3").files().list(q=query).execute()
        return response.get("files", [])[0]

@asset
def get_folder(gdrive: GoogleDriveClient) -> File:
    return gdrive.get_folder("My Folder")

defs = Definitions(assets=[get_folder], resources={"gdrive": GoogleDriveClient()})

This gives the error I mentioned above. I thought it might be because the

File

type is not available at

dagster

runtime because of the

TYPE_CHECKING

conditional import. The problem is that when I remove the conditional import (I think it’s standard for

mypy

these days), I get

ModuleNotFoundError: No module named 'googleapiclient._apis'

. That’s because

mypy

resolves the correct location in

site-packages

where the stubs were downloaded (

googleapiclient-stubs

), but I guess

dagster

doesn’t. Not really sure what to do… My understanding is the stubs I’ve downloaded are following all the standards. They work with

mypy

at least. Is there some way to tell

dagster

to find these correctly? Thanks in advance.

Thanks Tristian - if any issues aren't covered by these feel free to open one up and we'll take a look