ephraimbuddy commented on pull request #16823:
URL: https://github.com/apache/airflow/pull/16823#issuecomment-875037822
> Can you explain _why_ this is desirable behaviour?
>
> Doesn't returning a dictionary (and setting multiple outputs?) already set
different xcom keys, or am I making that up?
It does set different xcom keys for 'each' key in the dictionary and at the
end, the whole dictionary is also set with `return_value` as key.
What I want in this case, is to change this 'return_value' key that's
outputted which we don't have control over.
Take, for example, a python operator task that pushes xcom by returning a
value.:
```
def push_xcom(ti):
return [3,4,5,6]
task1 = PythonOperator(
task_id="push_xcom",
python_callable=push_xcom,
)
```
Here, we can't change the key for the xcom pushed, the only way to do it is
use
```
def push_xcom(ti):
ti.xcom_push(key='mykey', value=[3,4,5,6])
```
And in task decorator we can't change the xcom key used for this function :
```
@task()
def push_xcom(ti):
return [3,4,5,6]
```
If we use multiple_outputs and do something like:
```
@task(multiple_outputs=True)
def push_xcom(ti):
return {'mykey':[3,4,5,6]}
```
Then Xcoms pushed will be
```
key=mykey, value=[3,4,5,6]
key=return_value, value={'mykey':[3,4,56]}
```
With this change, if we have:
```
@task(xcom_key='mykey')
def push_xcom(ti):
return [3,4,5,6]
```
Xcom pushed will just be:
```
key=mykey, value=[3,4,5,6]
```
Which is mostly what anyone wants
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