sched.py 文件源码

def get_incremental_task(project_id, user_id=None, user_ip=None,
                         external_uid=None, offset=0, limit=1, orderby='id', desc=False):
    """Get a new task for a given project with its last given answer.

    It is an important strategy when dealing with large tasks, as
    transcriptions.
    """
    candidate_tasks = get_candidate_task_ids(project_id, user_id, user_ip,
                                                external_uid, limit, offset,
                                                orderby='priority_0', desc=True)
    total_remaining = len(candidate_tasks)
    if total_remaining == 0:
        return None
    rand = random.randrange(0, total_remaining)
    task = candidate_tasks[rand]
    # Find last answer for the task
    q = session.query(TaskRun)\
        .filter(TaskRun.task_id == task.id)\
        .order_by(TaskRun.finish_time.desc())
    last_task_run = q.first()
    if last_task_run:
        task.info['last_answer'] = last_task_run.info
        # TODO: As discussed in GitHub #53
        # it is necessary to create a lock in the task!
    return [task]