Allow variables to be printed to STDOUT with airflow variables export.

[vedantlodha]

---

This change allows airflow cli to export variables to stdout similar to connections using airflow variables export -.

Fixes #31851
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[pankajastro]

wondering if it makes sense to use AirflowConsole, it would allow print in multiple formats.

[vedantlodha]

If by console, you mean the UI, that makes sense, however this allows the cli to do so as well, similar to connections.

In the past i have had to switch between the cli and the UI for connections and variables.

[pankajastro]

If by console, you mean the UI, that makes sense, however this allows the cli to do so as well, similar to connections.

In the past i have had to switch between the cli and the UI for connections and variables.

In stdout only. I was thinking if we could print in different formats like json/yaml etc

But I see we do print in different formats for connection export like connection export - --file-format yaml but not for variables export command. so maybe it ok for now.

[utkarsharma2]

Can we please use more meaningful variable names instead of qry, var, val?

[vedantlodha]

Fair point. I just refactored the helper function into this. Will update the patch.

[utkarsharma2]

Suggested change

	except Exception:
	except json.decoder.JSONDecodeError:

[utkarsharma2]

It's always a good idea to handle specific exceptions as close to the source as possible.

[utkarsharma2]

This method doesn't really add much value, I would directly use fileio.name == "<stdout>" in line 96. Saves one lookup to a different method. :)

[vedantlodha]

Sure, this was just to maintain some consistency with connection_command.py's export. Will update the patch

[vedantlodha]

Thanks for the reviews @utkarsharma2. Updated the patch. Please take a look when you have some time.

[utkarsharma2]

Suggested change

	query = session.query(Variable).all()
	data = json.JSONDecoder()
	for variable in query:
	try:
	value = data.decode(variable.val)
	except json.decoder.JSONDecodeError:
	value = variable.val
	var_dict[variable.key] = value
	rows = session.query(Variable).all()
	data = json.JSONDecoder()
	for row in rows:
	try:
	value = data.decode(row.val)
	except json.decoder.JSONDecodeError:
	value = row.val
	var_dict[row.key] = value

Maybe something like this?

[uranusjr]

I think we can drop the all() as well since it’s only iterated once. Also why is the decoder called the data?

[vedantlodha]

Apologies for the delay, had been unwell lately.

Thanks for the inputs. Ive updated the patch.

[uranusjr]

Suggested change

	f.write(json.dumps(var_dict, sort_keys=True, indent=4))
	json.dump(f, var_dict, sort_keys=True, indent=4)

[github-actions]

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