Fix wrong parameter for drawDagStatsForDag() in dags.html

[XD-DENG]

I believe this is a typo. It should be states rather than stats.

Please refer to

airflow/airflow/www/templates/airflow/dags.html

Line 398 in 326c74e

.data(states)

and the signature of similar function drawTaskStatsForDag()

airflow/airflow/www/templates/airflow/dags.html

Line 467 in 326c74e

function drawTaskStatsForDag(dag_id, states) {

So far this is not causing any visible error/issue because of how scoping works in JavaScript.

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[kaxil]

cc @ryanahamilton

[ryanahamilton]

This is certainly a typo. With and without the fix, I see no issues in the browser. Would take a bit more effort to determine if/why it is necessary to be there at all.

[XD-DENG]

This is certainly a typo. With and without the fix, I see no issues in the browser. Would take a bit more effort to determine if/why it is necessary to be there at all.

Hi @ryanahamilton , yes you are right, there will be no issue without this fix. Because of the typo, this parameter is not useful/helpful at all. When .data(states) is called, it cannot find states in its current block, so it goes one level up, and states is available there

airflow/airflow/www/templates/airflow/dags.html

Lines 460 to 463 in 326c74e

	function dagStatsHandler(error, json) {
	for(var dag_id in json) {
	states = json[dag_id];
	drawDagStatsForDag(dag_id, states);

This may become a potential source of error/confusion though in the future, so fixing it.

[github-actions]

The PR is likely OK to be merged with just subset of tests for default Python and Database versions without running the full matrix of tests, because it does not modify the core of Airflow. If the committers decide that the full tests matrix is needed, they will add the label 'full tests needed'. Then you should rebase to the latest master or amend the last commit of the PR, and push it with --force-with-lease.