I have metadata on assets in my graph and I'm trying to query that metadata through the graphql endpoint. However, the

metadataEntries

are empty for all of my asssets. example query:

query RepositoriesQuery {
      repositoriesOrError {
        ... on RepositoryConnection {
          nodes {
            name
            assetNodes{
                assetKey {
                  path
                }
                metadataEntries {
                    label
                    description
                }
     ...

response has

metadataEntires:[]

for all assets despite seeing metadata in dagit.

Hi Drew, Are you able to create a minimal repro case? Like a

Definitions

object with one asset with metadata that is displaying this behavior.

Is there a simple dagster example repo somewhere? All the examples require environment variables and deployments and whatnot

Ah-- that’s because

context.add_output_metadata

does not add metadata to the assets definition. That puts metadata on the

AssetMaterialization

event. The metadata on the definition, which is what you’re querying in that GQL query, is set like this (also an example of a simple example of the kind I’m talking about):

from dagster import asset, Definitions

@asset(metadata={"foo": "bar"})
def foo_asset():
    return 1

defs = Definitions(
    assets=[foo_asset]
)

Put that in a file and run

dagster dev -f path/to/file

and your query should return the correct metadata.

is there a way to define asset metadata at output time in the io-manager?

There is not, but I think if you’re trying to do this you might have a fundamantal misconception of Dagster’s model. Dagster

AssetsDefinition

objects are basically wrappers around ops. They are a unit for buliding your data pipelines. They are defined when you load the code location, along with ops, jobs etc. They are not changed by Dagster runs. What is generated by runs are events. An

AssetMaterialization

is a kind of event, generated every time an asset’s materialization function is run. You modify the materialization generated by the current run when you use

add_output_metadata

.

So, I'm now doing

assetMaterializations {
              timestamp
              metadataEntries {
                label
                description
              }
              partition
            }

I'm getting the correct labels but all of the

description

fields are

None

in the graphql response despite being populated in the dagit ui?