correct the README and support podman

[jianzhangbjz]

Before this PR:

  File "/Users/jiazha/goproject/acto/acto/reproduce.py", line 93, in __init__
    raise RuntimeError(
RuntimeError: No CRs found in test/cassop-330/trial-demo. CR file name should start with mutated-
...
    raise child_exception_type(errno_num, err_msg, err_filename)
FileNotFoundError: [Errno 2] No such file or directory: 'docker'

After this PR:

jiazha-mac:acto jiazha$ export IMAGE_TOOL=podman
jiazha-mac:acto jiazha$ python3 -m acto.reproduce --reproduce-dir test/e2e_tests/test_data/cassop-330/trial-demo --config data/cass-operator/config.json

[tylergu]

Thanks @jianzhangbjz for the contribution! We probably would need to make additional modifications to Acto to fully support podman, as Kind by default still uses Docker. Will take a look later today.

[jianzhangbjz]

Thanks! One more question, can we support KUBECONFIG? I mean I have a alive cluster and want to run those tests on it instead of a new cluster created by the Kind.

[tylergu]

I believe supporting kubeconfig is totally possible. We would need to modify Acto a little bit.
One thing that maybe a concern is that, Acto currently runs multiple Kind clusters to parallelize testing. If we are given an existing cluster, then Acto has to be run in a single worker mode which could be very slow.
A potential solution is to utilize namespaces for parallelism, but that requires more thought.

[jianzhangbjz]

Hi @tylergu , got it, thanks!