Hi all How do I access a resource used by an asset from the

Question

Hi all How do I access a resource used by an asset from the IOmanager I ve specified a `ResourceDependency` in the IOmanager s class but it says that it is of type None

owen · Answer

hi < Noud Jaspers> do you mind sharing the code you re using

Noud Jaspers · Answer

```class PartitionedParquetObjectGCSIOManager ConfigurableIOManager postgres ResourceDependency PostgresResource def load input self context InputContext gt Any def handle output self context OutputContext tables Any gt None asset def polaris postgres PostgresResource return k postgres get table data k for k in postgres get tables defs = Definitions assets= polaris resources= io manager PartitionedParquetObjectGCSIOManager postgres PostgresResource connection string=get connection string config polaris db ```

Noud Jaspers · Answer

< owen> sure See the message above When I try to access postgres in the IOmanager it s None Any idea what I am doing wrong Thanks already

Noud Jaspers · Answer

I took <https github com dagster io dagster blob ad97f3c94d29687ac309281f735159648c2bbfd1 python modules libraries dagster gcp dagster gcp gcs io manager py L98|this> example and adapted it a little bit see the code here Same error gcs is None ```from dagster import Definitions asset ConfigurableResource ResourceDependency ConfigurableIOManager InputContext OutputContext from typing import Any class PostgresResource ConfigurableResource project str def get test return 1 2 3 45 class PartitionedParquetObjectGCSIOManager ConfigurableIOManager gcs ResourceDependency PostgresResource def load input self context InputContext gt Any def handle output self context OutputContext tables Any gt None print self gcs get test asset def asset1 create df return 1 2 3 4 5 6 asset def asset2 asset1 return asset1 5 defs = Definitions assets= asset1 asset2 resources= io manager PartitionedParquetObjectGCSIOManager gcs PostgresResource project= my cool project ```

Noud Jaspers · Answer

The full error is here ```dagster core errors DagsterExecutionHandleOutputError Error occurred while handling output result of step asset1 File home noud Documents Projects parthenon venv lib python3 10 site packages dagster core execution plan execute plan py line 262 in dagster event sequence for step for step event in check generator step events File home noud Documents Projects parthenon venv lib python3 10 site packages dagster core execution plan execute step py line 375 in core dagster event sequence for step for evt in type check and store output step context user event File home noud Documents Projects parthenon venv lib python3 10 site packages dagster core execution plan execute step py line 428 in type check and store output for evt in store output step context step output handle output File home noud Documents Projects parthenon venv lib python3 10 site packages dagster core execution plan execute step py line 603 in store output for elt in iterate with context File home noud Documents Projects parthenon venv lib python3 10 site packages dagster utils init py line 443 in iterate with context with context fn File usr lib python3 10 contextlib py line 153 in exit self gen throw typ value traceback File home noud Documents Projects parthenon venv lib python3 10 site packages dagster core execution plan utils py line 84 in op execution error boundary raise error cls The above exception was caused by the following exception AttributeError NoneType object has no attribute get test File home noud Documents Projects parthenon venv lib python3 10 site packages dagster core execution plan utils py line 54 in op execution error boundary yield File home noud Documents Projects parthenon venv lib python3 10 site packages dagster utils init py line 445 in iterate with context next output = next iterator File home noud Documents Projects parthenon venv lib python3 10 site packages dagster core execution plan execute step py line 593 in gen fn gen output = output manager handle output output context output value File home noud Documents Projects parthenon dagster prod prod init py line 54 in handle output print self gcs get test ```

ben · Answer

Hi Noud the IO manager in this case needs to be explicitly provided with the resource in question as a param when constructed

ben · Answer

The following should work ```gcs = PostgresResource project= my cool project defs = Definitions assets= asset1 asset2 resources= io manager PartitionedParquetObjectGCSIOManager gcs=gcs gcs gcs ```

ben · Answer

At present these dependencies need to be explicit There s a world where we might be able to enable something like this instead if that would substantially improve your experience ```defs = Definitions assets= asset1 asset2 resources= io manager PartitionedParquetObjectGCSIOManager gcs=ResourceByKey gcs gcs PostgresResource project= my cool project ```

Noud Jaspers · Answer

Hey < ben> thanks I ll provide it explicitly which is fine