MaxScopeReachedError¶

Symptom

Raised from build_child_container() called with no explicit scope= argument, naming the parent scope that has no deeper scope to advance to.

Cause

build_child_container() without an explicit scope= auto-derives the next deeper scope by picking the smallest enum member greater than the parent's. The built-in Scope enum ends at STEP; calling build_child_container() on a STEP-scope container has nowhere further to go.

Fix

Define a custom IntEnum scope with a member deeper than STEP and build the child with that scope explicitly:

import enum

from modern_di import Scope


class ExtendedScope(enum.IntEnum):
    APP = Scope.APP
    SESSION = Scope.SESSION
    REQUEST = Scope.REQUEST
    ACTION = Scope.ACTION
    STEP = Scope.STEP
    SUBSTEP = 6


step_container = Container(scope=ExtendedScope.STEP, parent_container=action_container)
sub_container = step_container.build_child_container(scope=ExtendedScope.SUBSTEP)

Root containers rarely need this — reconsider whether the provider actually needs a scope deeper than STEP, or whether it belongs at an existing shallower scope instead.

MaxScopeReachedError¶

See also¶