Create SSH access replacements for calls to docker.exec_run()

[ckunki]

Closes #304

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[ckunki]

I didn't see, if we have a integration test for the executor which only run these

I (again) admire your razor 🔪 eyes. 👀

We have

• integration tests test/integration/test_ssh_access.py which verify actual SSH access
• and unit tests test/unit/test_db_os_executor.py which verify the basic working of the executors and factories.

Up to now we do not have a dedicated integration test for executors and factories ...

... but we have parameterized tests in test/integration/test_bucketfs_upload.py which will cover full integration tests involving executors and factories as well, as soon as the implementation will be updated to actually use them. This is planned in ticket #305.

So if I can convince you to follow my explanation we could go this way.

Otherwise it would not bee too much effort to add dedicated integration tests for executors and factories. The only downside would be some additional runtime required in the CI build.

[tkilias]

Otherwise it would not bee too much effort to add dedicated integration tests for executors and factories. The only downside would be some additional runtime required in the CI build.

Hm, I am thinking about, if we can make these integration tests cheaper. In the sense, do we really need a database to test this functionality. I think, any ssh capable docker container should work.

[ckunki]

Hm, I am thinking about, if we can make these integration tests cheaper. In the sense, do we really need a database to test this functionality. I think, any ssh capable docker container should work.

OK: As aligned:

• I will add an integration test using docker container linuxserver/openssh-server:9.3_p2-r0-ls123
• compare script-languages/paramiko_connection_test.py

client.images.pull("panubo/sshd", tag="1.1.0")
container = client.containers.run(
    name="ssshd", 
    image="linuxserver/openssh-server:9.3_p2-r0-ls123",
    environment=[...])

Appropriate environment variables (see documentation on docker hub):

• PUBLIC_KEY
• PUBLIC_KEY_FILE