👋 everyone. I'm very new to Dagster as I'm trying to convert an existing script to a Dagster pipeline for the first time. This is not working: • I have a solid returning a dict • I have a downstream solid attempting to iterate through the dict • =>

Error loading repository location glue.py:dagster.core.errors.DagsterInvariantViolationError: Attempted to iterate over an InvokedSolidOutputHandle. This object represents the output "result" from the solid "load_partitions". Consider yielding multiple Outputs if you seek to pass different parts of this output to different solids.

New to dagster too and still learning. By any chance are any your solids returning multiple outputs? If so you'll have to define Output Definitions and return them by yielding the outputs.

Would you mind posting your code? Makes it easier to tell what's going on.

thanks for the reply, here is the code:

So I think the main issue here is that pipelines aren't intended to take inputs like this. database_name, input_table_names, new_table_name should all probably be specified via config

Using the context.config makes sense for these. yes

select_tables

is a solid. It pulls a list of tables from a data source.

Okay, gotcha. Yea so for example, you could parameterize select_tables like so:

@solid(config_schema={"database_name" str})
def select_tables(context):
    db_name = context.solid_config["database_name"]
    ....

And then in dagit, you can navigate to the playground, and provide this config there when executing. If using

execute_pipeline

, you can provide via the

run_config

argument. For more information on these aspects: Execution docs Run config docs (although I just found an error in these docs, the

config_example_solid

should have a config_schema defined lol. Gonna fix that.)

Got it @chris I'm trying to use context.config, how do I share config across solids?

@Remi Gabillet You may want to check out resources, which you can configure once and access from your solids https://docs.dagster.io/concepts/modes-resources

^ this is a super clean option as well. If you need to be able to change on a per-run basis, you can also use the

composite_solid

abstraction, which allows you to map config to internal solids: https://docs.dagster.io/concepts/solids-pipelines/composite-solids#configuration-mapping

thanks for the help everyone!