Airflow Generate Dynamic Tasks in Single DAG , Task N+1 is Dependent on TaskN

Question

When generating tasks dynamically, I need to have Task 2 be dependent of Task 1, Task1 >> Task 2 or task2.set_upstream(task1).

Since the task_ids are evaluated, or s

Answer 1

Use the following code:

a = []
for i in range(0,10):
    a.append(BashOperator(
        task_id='Component'+str(i),
        bash_command="echo  {{ ti.xcom_pull task_ids='SomeOtherTaskXcom', key='return_value') }} -z " + str(i) ,
        xcom_push=True,
        dag=dag))
    if i not in [0]: 
        a[i-1] >> a[i]

Using a DummyOperator, the codes looks like:

a = []
for i in range(0,10):
    a.append(DummyOperator(
        task_id='Component'+str(i),
        dag=dag))
    if i not in [0]: 
        a[i-1] >> a[i]

This would generate the following DAG: