rebase.artifact
Register a durable output URI on the current hosted run.
Signature
rb.artifact(
name: str,
*,
uri: str,
key: str | None = None,
disposition: Literal["created", "reused"] = "created",
media_type: str | None = None,
size_bytes: int | None = None,
version: str | None = None,
digest: str | None = None,
metadata: dict[str, Any] | None = None,
) -> rb.ArtifactRegister an output after writing it to durable storage:
artifact = rb.artifact(
"SE3 day-ahead forecast",
uri="gs://forecast-archive/2026-08-11/SE3.parquet",
key="forecast/SE3",
media_type="application/parquet",
size_bytes=218_420,
version="1741632447112345",
digest="md5:8d777f385d3dfec8815d20f7496026dc",
metadata={"zone": "SE3", "rows": 24},
)Rebase stores the pointer and metadata. It does not upload, copy, proxy, or validate the object itself.
Parameters
| Parameter | Description |
|---|---|
name | Required human-readable artifact name. |
uri | Required absolute URI with a scheme, such as gs://, s3://, or https://. |
key | Optional logical identity within the canonical run. The same key and URI is idempotent; another URI conflicts. |
disposition | "created" when this run wrote the output; "reused" when it found an existing output. |
media_type | Optional MIME type. |
size_bytes | Optional non-negative byte size. |
version | Optional storage generation, version, snapshot, or ETag. |
digest | Optional checksum. Include the algorithm in the value. |
metadata | Optional JSON object with domain-specific metadata. |
The returned Artifact exposes these fields plus its generated client_token and the
registered platform id. During local execution, id is None.
Attribution
Attribution is automatic:
- Inside
rb.task, the artifact belongs to that inline task. - Inside a
Function.mapchild run, it belongs to that map item and appears on the canonical parent workflow run. - Inside a workflow step without a task, it belongs to the step.
- Otherwise it belongs directly to the active run.
with rb.task("Export report", key="report") as task:
uri = export_report()
artifact = rb.artifact("Report", uri=uri, key="report/pdf", media_type="application/pdf")
task.set_result({"artifact_id": artifact.id, "uri": artifact.uri})Errors and Local Execution
ArtifactReportingError is raised if a hosted run cannot register the pointer. This is
strict by design: output that was successfully written should not silently disappear
from the run record.
Outside a hosted run, rb.artifact validates its arguments, returns an Artifact with
id is None, and makes no API request.
See Tasks and Artifacts for threaded and
Function.map examples that register artifacts.