How to use MVP management

When to use it

When the SUT can conceptually be defined as a telescope with resources that, when grouped together into a subarray, allows for performing configured scan as an atomic observation task.

The MVP management package assist a tester in ensuring a robust and correctly defined context, running tests on configured subarrays, whilst taking care of general health and monitoring; readiness checks (before and after SUT commands) and automatic setup and tear down of contexts.

What you need before starting

1. Skallop package installed. The package will automatically install these fixtures.

Setting up your environment

The MVP management package defines the SUT in generic terms using abstraction for objects related to telescope and subarrays. In order to set the concrete types the tester needs to configure the telescope type.

Configuring the telescope type

The skallop package automatically selects the correct type of telescope based on user defined configuration. To set this from a host env variable, either one of the following variable names must be used:

Var Name	Value meaning SKA Low	Value meaning SKA Mid
SKA_TELESCOPE	SKA-low	SKA-Mid
TEL	low	mid

Note that the env var TEL will be set when you setup remote connections using the setenv.sh command (see Setting ENV variables using script. )

Todo

Section describing how to change scope of readiness checks once merge for feature into master done.

Using MVP management

The example below illustrates the different context managers that can be used by each module and how they fit into each other.

from ska_ser_skallop.mvp_management import types
from ska_ser_skallop.mvp_management.subarray_composition import (
    allocate_subarray,
    generate_allocation_configuration,
)
from ska_ser_skallop.mvp_management.subarray_configuration import (
    configured_subarray,
    generate_scan_configuration,
)
from ska_ser_skallop.mvp_management.subarray_scanning import scanning_subarray
from ska_ser_skallop.mvp_management.telescope_management import (
    running_telescope,
    TelState,
)

settings = types.ExecSettings()
telescope_state = TelState()
receptors = [1, 2]
id = 1
sb = types.SBConfig(sbid="temp")
duration = 1
alloc = generate_allocation_configuration("standard")
scan_config = generate_scan_configuration("standard")

with running_telescope(settings, telescope_state):
    with allocated_subarray(receptors, id, alloc, sb, settings):
        with configured_subarray(id, receptors, scan_config, sb, duration, settings):
            with scanning_subarray(id, receptors, settings):
                alarm = generate_alarm_whilst_scanning()
                verify_alarm_handled(alarm)

Note that generate_alarm_whilst_scanning() and verify_alarm_handled() are for demonstration purpose only and not real functions.

As shown in the code above there is an implied order in the way one context can be used within another:

1. running_telescope()

2. allocated_subarray()

3. configured_subarray()

4. scanning_subarray()

Should the user opt to directly call tear down for each setup, the equivalent code for above would look as follows:

from ska_ser_skallop.mvp_management.telescope_management import (
    run_a_telescope,
    tear_down_a_telescope,
)
from ska_ser_skallop.mvp_management.subarray_composition import (
    compose_subarray,
    teardown_subarray,
)
from ska_ser_skallop.mvp_management.subarray_configuration import (
    configure_subarray,
    clear_subarray,
)
from ska_ser_skallop.mvp_management.subarray_scanning import (
    dispatch_scanning,
    clean_up_after_scan,
)

settings = types.ExecSettings()
telescope_state = TelState()
receptors = [1, 2]
id = 1
sb = types.SBConfig(sbid="temp")
duration = 1
alloc = generate_allocation_configuration("standard")
scan_config = generate_scan_configuration("standard")

run_a_telescope(settings)
compose_subarray(receptors, id, alloc, sb, settings)
configure_subarray(id, receptors, scan_config, sb, duration, settings)
scanning_job = dispatch_scanning(id, receptors, settings)
# end of setup code
alarm = generate_alarm_whilst_scanning()
verify_alarm_handled(alarm)
# start of tear down code
scanning_job.wait_for_scanning_to_complete()
clean_up_after_scan(id, receptors, settings)
clear_subarray(id, receptors, settings)
teardown_subarray(receptors, id, settings)
tear_down_a_telescope(settings)