[dualtor] Implement fixtures for test setup

[bingwang-ms]

Signed-off-by: bingwang [email protected]

Description of PR

Summary:
Fix #2834
This commit implements 4 new fixtures

1. set_upper_tor_active (function level)
2. set_lower_tor_active (function level)
3. set_upper_tor_active_module (module level)
4. set_lower_tor_active_module (module level)

Type of change

• Bug fix
• Testbed and Framework(new/improvement)
• Test case(new/improvement)

Approach

What is the motivation for this PR?

This PR is to implement several fixtures for dualtor test case setup.
For dualtor testcases, it's required to call one of these fixtures to ensure that the active ToR is expected.

How did you do it?

This PR implements 4 new fixtures.

How did you verify/test it?

Verified by a demo script

def test_demo_1(set_upper_tor_active):
    assert True

def test_demo_2(set_lower_tor_active):
    assert True

def test_demo_3(set_upper_tor_active_module):
    assert True

def test_demo_4(set_lower_tor_active_module):
    assert True

Any platform specific information?

No.

Supported testbed topology if it's a new test case?

Dualtor specific.

Documentation

[theasianpianist]

Please use the mux simulator to change the active ToR. Using the CLI commands should be reserved for the test cases that require manually changing the active ToR. Since the CLI commands are a feature that is being tested, we don't want to use them elsewhere.

[vaibhavhd]

I agree, we should use MUX simulator for toggle usecases. But, what is force_active_tor helper to be used for?
We should also make the fixtures in MUX simulator as function scope instead of module.

[vaibhavhd]

This also makes me ask why do we need this fixtures when we have similar task being done by fixtures present in mux_simulator_control.py?
toggle_all_simulator_ports_to_lower_tor()
toggle_all_simulator_ports_to_upper_tor()
.....

[bingwang-ms]

I think using CLI is better than using the mux_simulator interfaces. Actually, the CLI will call mux_simulator at last. These fixtures are intended to be used before dualtor test cases that require a certain ToR as active.
In other word, I don't think we should call mux_simulator interfaces directly. Test cases should do what human do. So I think CLI is a better choice.

[theasianpianist]

Same as above

[bingwang-ms]

Thanks. Will update.

[theasianpianist]

Same as above

[theasianpianist]

Same as above, plus add newline to EOF

[bingwang-ms]

The PR is no longer needed as we already have toggle_all_simulator_ports_to_lower_tor() and toggle_all_simulator_ports_to_upper_tor() in mux_simulator_control.py. So close.