Asset Loading

load_rocky_assets() returns one Dagster AssetSpec for every enabled table across all your Rocky sources. An AssetSpec declares an asset to Dagster without attaching a function that computes it. Use this when you want the asset list to follow your sources, instead of writing out each table by hand.

From rocky discover to AssetSpec

load_rocky_assets() calls rocky discover, which asks each configured source which tables it holds. Every enabled table becomes one AssetSpec. The asset key, group, tags, and metadata all come from the source and the table, using the rules below.

Default mappings

Asset key

The default asset key is constructed from the source type, component values, and table name:

[source_type, *component_values, table_name]

For example, a table orders from a Fivetran source with components tenant=acme, regions=us_west, connector=shopify produces:

["fivetran", "acme", "us_west", "shopify", "orders"]

Group

The default group name is the first component whose value is a string. Components whose value is a list are skipped. If every component is list-valued, the group falls back to the source type. In the example above, the group is "acme".

Tags

• rocky/source_type – the source type (e.g., "fivetran")
• rocky/<component_name> – one tag per string component (e.g., rocky/tenant: "acme")

Metadata

• source_id – the source identifier
• source_type – the source type
• last_sync_at – timestamp of the last sync
• row_count – number of rows in the table

Example

from dagster_rocky import RockyResource, load_rocky_assets
import dagster as dg

rocky = RockyResource(config_path="rocky.toml")
assets = load_rocky_assets(rocky)

defs = dg.Definitions(
    assets=assets,
    resources={"rocky": rocky},
)

Custom translation

Pass a custom translator to change how sources and tables map to Dagster keys, groups, tags, and metadata. See Translator for the methods you can override.

assets = load_rocky_assets(rocky, translator=MyTranslator())