Tracking previous tasks

Registered by Renat Akhmerov

We need to be able to track task executions previous to the given task. This is mostly needed for UI.

We also need to see on what event (on-success, on-error) the task was started. and we need to support the following case too:

tasks:
    taskA:
        ...
    on-success:
        - taskB
    on-complete:
        - taskB

Blueprint information

Status:
Complete
Approver:
Renat Akhmerov
Priority:
High
Drafter:
Renat Akhmerov
Direction:
Approved
Assignee:
Renat Akhmerov
Definition:
Approved
Series goal:
None
Implementation:
Implemented
Milestone target:
milestone icon pike-2
Started by
Renat Akhmerov
Completed by
Renat Akhmerov

Related branches

Sprints

Whiteboard

Gerrit topic: https://review.openstack.org/#q,topic:bp/mistral-previous-tasks,n,z

Addressed by: https://review.openstack.org/457184
    Add 'prev_task_id' into task execution runtime context

Addressed by: https://review.openstack.org/457996
    WIP: make "trigger_by" work in case of "join" tasks

Addressed by: https://review.openstack.org/458000
    Add 'runtime_context' to task execution REST resource

(?)

Work Items

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