Return files destination uris in all to_<storage> operators

[FHoffmannCode]

Description

Currently some storage operators return files destination uris list for example GoogleSheetsToGCSOperator. It would be a good idea to make all of such operators to return this list.

Use case / motivation

1. Having list of destination uris for files transferred with operator is useful for debugging and troubleshooting
2. Inconsistent operator behaviour might be confusing for users.

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[eladkal]

This issue spawn from https://github.com/apache/airflow/pull/10991#discussion_r500837769 It probably can be useful but it's also a breaking change and so far I didn't see users complaining about it. Could you please clarify the TODO part on this issue? What operators need adjustments? Is it localized to GCP or also other providers?

[uranusjr]

Yeah I don’t see how this could break user code in practice. Should be doable.

[potiuk]

Yeah. Nice feature to add. Would you like to implement it @FHoffmannCode ? Should I assign it to you ?

[eladkal]

Yeah I don’t see how this could break user code in practice.

The suggestion was to change the returned value to make operators consistent. If changed then the value pushed to xcom is not as users are expecting.

[uranusjr]

It depends on what are correctly being returned; I’m assuming most (if not all) are currently returning None, which won’t have backward compatibility issues (except if someone is depending on an XCom is not pushed, but why would anyone do that). Are there instances of an operator currently pushing something else?

[potiuk]

Yeah. Same here. I think it's no harm to return "more".

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This issue has been automatically marked as stale because it has been open for 30 days with no response from the author. It will be closed in next 7 days if no further activity occurs from the issue author.

[shahar1]

@eladkal Please assign me

[potiuk]

assigned