Add new helper for matching reauth/reconfigure config flows

[epenet]

Breaking change

Proposed change

When using reauth/reconfigure, there is currently no easy way to check that the unique_id of the original entry still matches what the new unique_id would be with the latest input.
This is especially obvious when reauth/reconfigure flows reuse existing functionnality from user flow.

I propose that we add this helper to make it easier to bail out if there is a mismatch:

Sample use:

await self.async_set_unique_id(uid)
if self.source == SOURCE_REAUTH:
    self._abort_if_unique_id_mismatch(reason="reauth_account_mismatch")
    return self.async_update_reload_and_abort(self._get_reauth_entry(), data=data)
self._abort_if_unique_id_configured()
return self.async_create_entry(title=uid, data=data)

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)
• Deprecation (breaking change to happen in the future)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue: fixes #
• This PR is related to issue:
• Link to documentation pull request: Document _abort_if_unique_id_mismatch helper developers.home-assistant#2353

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[home-assistant]

Hey there @frenck, @joostlek, mind taking a look at this pull request as it has been labeled with an integration (spotify) you are listed as a code owner for? Thanks!

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[frenck]

I'm not sure if we should assume the unique ID is being used for detecting these cases.

[frenck]

I think it makes sense to add this helper.

Can you elaborate on that? There is nothing in the PR description that explain the foundation behind it.

[epenet]

I think it makes sense to add this helper.

Can you elaborate on that? There is nothing in the PR description that explain the foundation behind it.

It's a pattern I've bumped into a few times. Axis and abode for example use this pattern.
It was used by integrations when reconfigure wasn't available.
I'll look for more examples on Monday

[epenet]

I think it makes sense to add this helper.

Can you elaborate on that? There is nothing in the PR description that explain the foundation behind it.

It's a pattern I've bumped into a few times. Axis and abode for example use this pattern. It was used by integrations when reconfigure wasn't available. I'll look for more examples on Monday

It's also partially linked to #127527

[epenet]

I'll look for more examples on Monday

Here's another example I've just bumped into, which I think would benefit from this:
https://github.com/home-assistant/core/pull/127726/files#r1789215553

[epenet]

I think it makes sense to add this helper.

Can you elaborate on that? There is nothing in the PR description that explain the foundation behind it.

• I have adjusted the PR description
• I have added a documentation PR
• I have added tests
• I have applied the helper to three integrations that already have some of this logic implemented, to show the benefit
  • bmw_connected_drive
  • spotify
  • tesla_fleet

[frenck]

Honestly, I find the use-case/gain to shallow to add a helper. While helpers can be helpful, they can also make code harder to read / harder to follow (as one has to jump between more logic).

I'm not sure on this one. Going to ask for a second opinion from another reviewer.

../Frenck

[epenet]

Honestly, I find the use-case/gain to shallow to add a helper. While helpers can be helpful, they can also make code harder to read / harder to follow (as one has to jump between more logic).

I'm not sure on this one. Going to ask for a second opinion from another reviewer.

../Frenck

One more note: it is a mirror to self._abort_if_unique_id_configured that cannot be used inside reauth/reconfigure flows.

[MartinHjelmare]

I think it's nice since it will help integrations to do the right thing. I think there are many integrations that have reauth flows where they don't check that the flow is reauthenticating matching flow data.

[frenck]

Thanks, @epenet 👍

../Frenck