Add calculate_sha256 management command to trigger (re)computation for a blob

.codespellrc

@@ -1,5 +1,5 @@
 [codespell]
-skip = .git,node_modules,dist,venv,.venv,.mypy_cache,.tox,yarn.lock,CHANGELOG.md,./htmlcov,*.pyc,*.log
+skip = .git,node_modules,dist,venv,.venv,.mypy_cache,.tox,yarn.lock,CHANGELOG.md,./htmlcov,*.pyc,*.log,build,venvs
 # Disabled until https://github.com/codespell-project/codespell/issues/2727
 # got answer/re-solution
 # dictionary = .codespell_dict

dandiapi/api/management/commands/calculate_sha256.py

@@ -0,0 +1,28 @@
+from __future__ import annotations
+
+import djclick as click
+
+from dandiapi.api.models import Asset
+from dandiapi.api.tasks import calculate_sha256 as do_calculate_sha256
+
+
+@click.command()
+@click.option('--blob-id', 'blob_id', help='Blob ID')
+@click.option('--asset-id', 'asset_id', help='Asset ID')
+def calculate_sha256(asset_id: str | None = None, blob_id: str | None = None):
+    """Trigger computation of sha256 for a blob.
+
+    Either blob-id or asset-id should be provided.
+    """
+    # Handle mutually exclusive option failure cases.
+    if not asset_id and not blob_id:
+        raise ValueError('Provide either asset_id or blob_id')
+    if asset_id and blob_id:
+        raise ValueError('Provide only asset_id or blob_id, not both')
+
+    # Make sure we have a good blob_id to work with.
+    if asset_id:
+        asset = Asset.objects.get(asset_id=asset_id)
+        blob_id = asset.blob_id
+
+    do_calculate_sha256(blob_id=blob_id)