Remove resources selection from Nut config flow

[ollo69]

Proposed change

Remove the initial selection of Nut resources from the config flow. Only main resources will be automatically enabled, all the others are created in state disabled. Import of existing configuration is implemented.
Test has been changed to not consider anymore the CONF_RESOURCES settings.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

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• This PR fixes or closes issue: fixes #
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[probot-home-assistant]

Hey there @bdraco, mind taking a look at this pull request as it has been labeled with an integration (nut) you are listed as a code owner for? Thanks!
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[MartinHjelmare]

I think we should remove this check. It's not the config flow responsibility to determine available sensors. The config flow should just validate the connection with the provided config data and then create the entry if the connection to the device or service is successful.

[ollo69]

This could eventually create integration without entity. is this OK? Before it was not possible because user was forced to select at least 1 resource to complete the config flow.

[MartinHjelmare]

I think we should create a device entry for the UPS explicitly if this isn't already done. Then there will always be at least a device entry. The entities is ok to not be any.

[MartinHjelmare]

Will you follow up with a PR to add a device explicitly to the device registry?

[ollo69]

Sorry, I lost this point. There is a reference to an integration that do the same, I never did it?

[MartinHjelmare]

Here's an example:

core/homeassistant/components/bond/__init__.py

Lines 72 to 81 in c03fdd5

	device_registry = dr.async_get(hass)
	device_registry.async_get_or_create(
	config_entry_id=config_entry_id,
	identifiers={(DOMAIN, hub.bond_id)},
	manufacturer=BRIDGE_MAKE,
	name=hub_name,
	model=hub.target,
	sw_version=hub.fw_ver,
	suggested_area=hub.location,
	)

[MartinHjelmare]

Should we merge this PR, and save it for a follow up, or do you want to do it here?

[ollo69]

Yes, please, merge it, I will create follow up.

[MartinHjelmare]

Looks good!