Use dataclass for DhcpServiceInfo

[epenet]

Breaking change

Dhcp discovery now uses a dataclass instead of a dictionary object.
Access using __getitem__ will fail in version 2022.6.
Please use <cls>.<name> instead.

Proposed change

Dhcp discovery now uses a dataclass instead of a dictionary object.
Access using __getitem__ will fail in version 2022.6.
Please use <cls>.<name> instead.

Linked to this comment in the architecture discussion home-assistant/architecture#662 (comment)

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• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
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• Breaking change (fix/feature causing existing functionality to break)
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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 (dhcp) you are listed as a code owner for? Thanks!
_{^{(message by CodeOwnersMention)}}

[epenet]

cc @Jc2k for the original idea

[epenet]

Side note: is there any way for a developper to stop actions and release the CI agents on their own PR?

[epenet]

And I think this needs the breaking-change label added.

[bdraco]

LGTM 👍

I like this solution quite a bit more.

[MartinHjelmare]

The data_entry_flow, config_entries and helpers will need to be updated to support this. They expect and have types for user_input as dict.

[epenet]

@MartinHjelmare am I missing something?

data_entry_flow.py should not require amends (the discovery steps are not called by the UI)

config_entries.py is ready for this:

core/homeassistant/config_entries.py

Lines 1383 to 1387 in 4aae088

	async def async_step_dhcp(
	self, discovery_info: DhcpServiceInfo
	) -> data_entry_flow.FlowResult:
	"""Handle a flow initialized by DHCP discovery."""
	return await self.async_step_discovery(cast(dict, discovery_info))

helpers/config_entry_flow.py is ready for this also:

core/homeassistant/helpers/config_entry_flow.py

Lines 86 to 93 in 4aae088

	async def async_step_dhcp(self, discovery_info: dhcp.DhcpServiceInfo) -> FlowResult:
	"""Handle a flow initialized by dhcp discovery."""
	if self._async_in_progress() or self._async_current_entries():
	return self.async_abort(reason="single_instance_allowed")
	await self.async_set_unique_id(self._domain)
	return await self.async_step_confirm()

Components can continue using discovery_info[ATTR]

[MartinHjelmare]

When the flow is started the data entry flow manager eventually calls _async_handle_step before we reach the config flow module step of the integration. _async_handle_step takes user_input which has type dict | None.

core/homeassistant/data_entry_flow.py

Line 304 in 4aae088

user_input: dict | None,

[epenet]

Is this the only place where something is missing?

I can adjust the type hint:
user_input: dict | DhcpServiceInfo | MqttServiceInfo | UsbServiceInfo | None,

Or create a base class BaseServiceInfo that the other inherit from:
user_input: dict | BaseServiceInfo | None,

[MartinHjelmare]

I looked over it briefly now and I think that's the only place. The other places already had the data input typed as Any.

Any of the above suggestions are fine. The latter is shorter and more easily extendable so I'd recommend that.

[epenet]

All checks have passed, the comments from @MartinHjelmare have been addressed.
Is there anything else missing in this PR?

[MartinHjelmare]

Thanks!