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!

[jianzhangbjz]

Hi @tylergu , any updates about the kubeconfig supporting? Thanks!

[tylergu]

I can start working on it. The only blocker that I have is how to mock a cluster cleanup in a user-provided cluster---Acto currently assumes that it owns the cluster and directly deletes and recreates clusters to clean up things in between each test. If we are running on an existing cluster, maybe we should support namespace-based isolation so that we don't have to delete the cluster to clean up, instead we delete namespaces. We probably also don't want to mess with other things in the cluster during the testing.

@jianzhangbjz I will give a try to support kubeconfig, and Acto is going to run in a single worker mode.

[jianzhangbjz]

Great! Thanks!