dheerajturaga commented on code in PR #71808:
URL: https://github.com/apache/airflow/pull/71808#discussion_r3889964640
##########
providers/standard/docs/operators/bash.rst:
##########
@@ -226,6 +226,58 @@ Here's how you can use the result_processor with the
BashOperator:
)
+Multiple XCom outputs
+---------------------
+
+Pair ``output_processor`` with ``multiple_outputs=True`` to push more than one
XCom from a single task. When
+the processed output is a dictionary, each key is pushed as its own XCom,
which lets downstream tasks pull
+individual values by name instead of pulling the whole dictionary and indexing
into it.
+
+.. tab-set::
+
+ .. tab-item:: @task.bash
+ :sync: taskflow
+
+ .. exampleinclude::
/../src/airflow/providers/standard/example_dags/example_bash_decorator.py
+ :language: python
+ :dedent: 4
+ :start-after: [START howto_decorator_bash_multiple_outputs]
+ :end-before: [END howto_decorator_bash_multiple_outputs]
+
+ .. tab-item:: BashOperator
+ :sync: operator
+
+ .. exampleinclude::
/../src/airflow/providers/standard/example_dags/example_bash_operator.py
+ :language: python
+ :dedent: 4
+ :start-after: [START howto_operator_bash_multiple_outputs]
+ :end-before: [END howto_operator_bash_multiple_outputs]
+
+The producing task above pushes an XCom for ``dag_folder`` and one for
``file_count``. The full dictionary is
+*also* pushed as the task's return value, so ``{{
ti.xcom_pull(task_ids="describe_dag_folder") }}`` still
+resolves to ``{"dag_folder": ..., "file_count": ...}``.
+
+.. important::
+
+ Only the **last line** written by the command is captured, so the
dictionary must be the final thing the
+ command emits. A few consequences worth designing around:
+
+ * A trailing ``echo`` with no arguments emits an empty line, which becomes
the captured output instead of
+ your dictionary.
+ * ``stderr`` is merged into ``stdout``, so a subcommand that writes to
``stderr`` last will overwrite the
+ captured value. Redirect noisy subcommands (for example ``2>/dev/null``)
to avoid this.
+ * The dictionary must fit on a single line. Use ``jq -c`` rather than
pretty-printed output, and prefer
+ ``printf`` over a multi-line ``printf`` format string.
+ * Every line the command writes is sent to the task log, including the
line holding your values. Avoid
+ emitting secrets this way.
Review Comment:
Fair, I removed this comment for now. This was a general guidance anyway
unrelated to the scope of this PR
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: [email protected]
For queries about this service, please contact Infrastructure at:
[email protected]
