Fix tree view if config contains "

[Khrol]

#9251

If you run DAG with {"\"": ""} configuration tree view will be broken:

tree:1 Uncaught SyntaxError: Unexpected string in JSON at position 806
    at JSON.parse (<anonymous>)
    at tree?dag_id=hightlight_test&num_runs=25:1190

JSON.parse is given incorrectly escaped json string.

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[mik-laj]

Have you checked whether the problem also occurs elsewhere? Similar problems like to be repeated.

[Khrol]

@mik-laj I've checked the code by JSON.parse calls. Nothing similar.

[ashb]

We're holding off merging anything until we've fixed tests though. Should be done soon

[ashb]

Yeah, this used to be just var data = {{ data | tojson }} but for large dags (i.e. AirB'n'B scale) this was a slow down on rendering the web page.

[mik-laj]

It seems that this change has broken the tests on the master branch.
Last valid build on master:
https://github.com/apache/airflow/runs/772104379
Next finished build on master:
https://github.com/apache/airflow/runs/772331104

[Khrol]

@mik-laj tests were green on PR... Do you want me to fix tests or you can do it?

[mik-laj]

It was green, but it was this build that ended three days ago. I am already working on it.

[kaxil]

The problem with the CI in this build was that it only tested the static tests. As no ".py" file was changed, CI skipped rest of the unit test. However on Master we run all the tests, hence Master failed with below error:

tests/www/test_views.py .............................F

_________ TestAirflowBaseViews.test_escape_in_tree_view_0_hello_world __________

a = (<tests.www.test_views.TestAirflowBaseViews testMethod=test_escape_in_tree_view_0_hello_world>,)

    @wraps(func)
    def standalone_func(*a):
>       return func(*(a + p.args), **p.kwargs)

/usr/local/lib/python3.6/site-packages/parameterized/parameterized.py:530: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
tests/www/test_views.py:646: in test_escape_in_tree_view
    self.check_content_in_response(f'"conf":{{"abc":"{seralized_test_str}"}}', resp)
tests/www/test_views.py:177: in check_content_in_response
    self.assertIn(text, resp_html)

tests/www/test_views.py F

_________ TestAirflowBaseViews.test_escape_in_tree_view_1_hello_world __________

a = (<tests.www.test_views.TestAirflowBaseViews testMethod=test_escape_in_tree_view_1_hello_world>,)

    @wraps(func)
    def standalone_func(*a):
>       return func(*(a + p.args), **p.kwargs)

/usr/local/lib/python3.6/site-packages/parameterized/parameterized.py:530: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
tests/www/test_views.py:646: in test_escape_in_tree_view
    self.check_content_in_response(f'"conf":{{"abc":"{seralized_test_str}"}}', resp)
tests/www/test_views.py:177: in check_content_in_response
    self.assertIn(text, resp_html)
E   AssertionError: '"conf":{"abc":"hello\\\\u0027world"}' not found in '\n\n\n\n\n\n\n\n\n\n 

[mik-laj]

I finished change: Here is PR: #9307