[AIRFLOW-6370] Skip Cassandra tests if cluster is not up

[turbaszek]

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Jira

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  • https://issues.apache.org/jira/browse/AIRFLOW-6370

Description

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  This PR add skipIf decorator for Cassandra hook tests and improves mocking in sensors tests. The decorator should eliminate flaky tests.

Tests

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[codecov-io]

Codecov Report

Merging #6926 into master will decrease coverage by 0.29%.
The diff coverage is n/a.

@@            Coverage Diff            @@
##           master    #6926     +/-   ##
=========================================
- Coverage   84.72%   84.42%   -0.3%     
=========================================
  Files         679      679             
  Lines       38518    38518             
=========================================
- Hits        32634    32519    -115     
- Misses       5884     5999    +115

Impacted Files	Coverage Δ
airflow/contrib/hooks/cassandra_hook.py	0% <0%> (-100%)	⬇️
airflow/kubernetes/volume_mount.py	44.44% <0%> (-55.56%)	⬇️
airflow/kubernetes/volume.py	52.94% <0%> (-47.06%)	⬇️
airflow/kubernetes/pod_launcher.py	45.25% <0%> (-46.72%)	⬇️
airflow/kubernetes/refresh_config.py	50.98% <0%> (-23.53%)	⬇️
...rflow/contrib/operators/kubernetes_pod_operator.py	78.75% <0%> (-20%)	⬇️
airflow/jobs/backfill_job.py	91.59% <0%> (-0.29%)	⬇️

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[turbaszek]

It seems that the problem persists:
https://travis-ci.org/apache/airflow/jobs/630369640

The test is not skipped so connection can be established? Default port is used in both cases.

@potiuk @mik-laj do you have any ideas?

[potiuk]

I restarted it too quickly. I will take a look next time it happens (or maybe we manage to move to github before ;)