diskimage-builder/diskimage_builder/block_device/tests/config/rollback.yaml

- test_a:
    name: test_node_a
    rollback_one_arg: down
    rollback_two_arg: you

- test_b:
    base: test_node_a
    name: test_node_b
    rollback_one_arg: let
    rollback_two_arg: gonna

- test_a:
    base: test_node_b
    name: test_node_aa
    rollback_one_arg: never
    rollback_two_arg: up

- test_b:
    base: test_node_aa
    name: test_node_bb
    rollback_one_arg: you
    rollback_two_arg: give

- test_a:
    base: test_node_bb
    name: test_node_aaa
    rollback_one_arg: gonna
    rollback_two_arg: never
    trigger_rollback: yes
Move rollback into NodeBase object Currently we pass a reference to a global "rollback" list to create() to keep rollback functions. Other nodes don't need to know about global rollback state, and by passing by reference we're giving them the chance to mess it up for everyone else. Add a "add_rollback()" function in NodeBase for create() calls to register rollback calls within themselves. As they hit rollback points they can add a new entry. lambda v arguments is much of a muchness -- but this is similar to the standard atexit() call so with go with that pattern. A new "rollback()" call is added that the driver will invoke on each node as it works its way backwards in case of failure. On error, nodes will have rollback() called in reverse order (which then calls registered rollbacks in reverse order). A unit test is added to test rollback behaviour Change-Id: I65214e72c7ef607dd08f750a6d32a0b10fe97ac3 2017-06-02 00:57:06 +00:00			`- test_a:`
			`name: test_node_a`
			`rollback_one_arg: down`
			`rollback_two_arg: you`

			`- test_b:`
			`base: test_node_a`
			`name: test_node_b`
			`rollback_one_arg: let`
			`rollback_two_arg: gonna`

			`- test_a:`
			`base: test_node_b`
			`name: test_node_aa`
			`rollback_one_arg: never`
			`rollback_two_arg: up`

			`- test_b:`
			`base: test_node_aa`
			`name: test_node_bb`
			`rollback_one_arg: you`
			`rollback_two_arg: give`

			`- test_a:`
			`base: test_node_bb`
			`name: test_node_aaa`
			`rollback_one_arg: gonna`
			`rollback_two_arg: never`
			`trigger_rollback: yes`