ChildContainerRegistrationError

Symptom

Raised from Container.add_providers(), naming the scope of the child container it was called on.

Cause

add_providers() was called on a child container rather than the root. The providers registry is shared tree-wide (every container in the chain points at the same registry), so registering from a child would silently mutate every container in the tree — this is disallowed rather than done implicitly.

Fix

Call add_providers() on the root container instead:

app_container = Container(scope=Scope.APP, groups=[MyGroup])
request_container = app_container.build_child_container(scope=Scope.REQUEST)

# Wrong
request_container.add_providers(late_provider)  # raises ChildContainerRegistrationError

# Right
app_container.add_providers(late_provider)

If you only have a reference to the child container at the call site, keep a reference to the root container around (e.g. store it at app startup) instead of walking up via parent_container.

See also

• Container: registering providers after construction.