HomeKit support

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Is your feature request related to a problem? Please describe.
Nope, just hoping to use the framework.

Describe the solution you'd like
Would it be possible to just get from HomeKit import HMHomeManager to work?

Describe alternatives you've considered
The various HomeKit libraries in Python seem to be for cutting Apple out of the loop entirely (implementing a controller on Linux or emulating an accessory), so I don't think there's something that does this.

[ronaldoussoren]

A possible issue is that HomeKit is a catalyst framework. That said, AFAIK it is possible to mix usage of catalyst in cocoa in applications.

[ronaldoussoren]

The following has limited success:

import objc
objc.loadBundle('HomeKit', globals(), '/System/Library/PrivateFrameworks/HomeKit.framework')
manager = HMHomeManager.new()
print(manager.homes())

This works, but prints an empty set of homes even though I see a "home" in Home.app.

Loading /System/iOSSupport/System/Library/Frameworks/HomeKit.framework (which Home.app uses) doesn't work for me, I get a generic "Bundle could not be loaded" error.

Using NSBundle.bundleWithPath_ to load the latter framework gives a clearer error message:

 2022-10-15 21:56:36.971 Python[91353:14405081] Error loading /System/iOSSupport/System/Library/Frameworks/HomeKit.framework/HomeKit:  dlopen(/System/iOSSupport/System/Library/Frameworks/HomeKit.framework/HomeKit, 0x0109): tried: '/System/iOSSupport/System/Library/Frameworks/HomeKit.framework/Versions/A/HomeKit' (wrong platform to load into process), '/System/Library/Frameworks/HomeKit.framework/Versions/A/HomeKit' (no such file)

Some very short research seems to indicate that it is possible to load an AppKit extension into a Catalyst app, but that it is at best a lot harder to do it the other way around (https://indiedevmonday.com/issue-18, https://github.com/steventroughtonsmith/airqualitymonitor, https://twitter.com/stroughtonsmith/status/1313474865467453441).

More importantly: https://developer.apple.com/forums/thread/692356, which contains a definitive statement from an Apple engineer that says loading Catalyst frameworks into an AppKit app is not possible.

That sadly means that using the HomeKit framework requires either using the private HomeKit framework (assuming that can be made to work), or creating a Catalyst version of Python + PyObjC. That's something I'd like to look into, but I have no idea when.

[ronaldoussoren]

A Catalyst version of Python would be an interesting proposition, but is something that will require coordinating with at least the PyPA and PyPI maintainers, as well as with CPython to upstream relevant patches (including CI support).

A major disadvantage of a Catalyst Python is that it likely cannot use existing binary wheels.

[ronaldoussoren]

I've added an issue about a Catalyst build to the CPython project: python/cpython#98297

To be honest I expect little progress on that until I get around to work on this myself (assuming I do get around to that).

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Trying this again on Sequoia, I notice that I do get this prompt now:

I allow Terminal access, but .homes() is still empty.

However, there's a bunch of instructions for junk to dump into your info.plist, which neither Terminal.app nor Python Launcher.app have: https://developer.apple.com/documentation/homekit/enabling-homekit-in-your-app?language=objc

It claims that if you request permission without filling out this data, your app will immediately crash when you try to use HomeKit, which is obviously wrong. I wonder if a simple py2app app with the relevant entitlement would do the trick.

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Hm. Bummer. I thought I'd be able to get a permission denial from this process, but I pulled in some constants from the .h file, and:

>>> mgr.authorizationStatus() == HMHomeManagerAuthorizationStatusAuthorized | HMHomeManagerAuthorizationStatusDetermined
True

[ronaldoussoren]

Hm. Bummer. I thought I'd be able to get a permission denial from this process, but I pulled in some constants from the .h file, and:

>>> mgr.authorizationStatus() == HMHomeManagerAuthorizationStatusAuthorized | HMHomeManagerAuthorizationStatusDetermined
True

I get the same response (and can drop the AuthorizedStatus bit using system settings).

I've tried adding the info.plist key to the Python.app in the framework (python.org installer, with ad-hoc signatures to enable debugging using lldb), but that doesn't help either.

Likewise for adding a runloop, e.g.:

import objc
from Cocoa import NSRunLoop, NSDate, NSObject, NSApplication
objc.loadBundle('HomeKit', globals(), '/System/Library/PrivateFrameworks/HomeKit.framework')

class Delegate(NSObject):
    def homeManagerDidUpdateHomes_(self, manager):
        print("homes updates", manager.hmes())

    def homeManager_didAddHome_(self, manager, home):
        print("homes added home", manager, home)

    def homeManager_didRemoveHome_(self, manager, home):
        print("homes added home", manager, home)

app = NSApplication.sharedApplication()
delegate = Delegate()
manager = HMHomeManager()
manager.setDelegate_(delegate)
print(manager.authorizationStatus())
print(manager.homes())
print(manager.primaryHome())

NSRunLoop.currentRunLoop().runUntilDate_(NSDate.dateWithTimeIntervalSinceNow_(5))
#app.run()

print(manager.authorizationStatus())
print(manager.homes())
print(manager.primaryHome())

This prints the same information both times, and none of the delegate methods are called. Using 'app.run' instead doesn't change the latter build (but does require killing the script because the runloop won't stop).

So close, yet so far way :-(

[glyph]

I didn't do the Info.plist tweak, but on the suspicion that the issue might have been "HomeKit = Catalyst = UIKit, UIKit doesn't like being in a process with AppKit" I tried to stick to Foundation and CoreFoundation and did the same thing with a CFRunLoop instead, and … same result. Understanding this is definitely beyond my abilities at this point.

[ronaldoussoren]

Interestingly enough there is a /System/Library/Frameworks/HomeKit.framework in the first macOS 26.4 beta, although no headers.

It might be possible to expose this framework using the iOS/Catalyst headers as a source for definitions that cannot be extracted from the ObjC runtime.

To be continued...

[ronaldoussoren]

And indeed: the demo script no longer gives an error, but also doesn't show anything.

This might be due to needing to add an entitlement and Info.plist key.

Current plan is to add an experimental framework binding based on the iOS headers, and a small example that interacts with HomeKit.

[ronaldoussoren]

Little success so far to get this actually working: The script works, but doesn't return any home information. This might be related to code signing (I'm using ad-hoc signing without any options or entitlements).

With a small script using py2app I get:

• When opening the app I get a popup about allowing the app to access homes
• The delegate callback for changed authorization status fires
• Other delegate callbacks do not get called
• The list of homes stays empty

The script is basically the same as above.

An attempt using entitlements doesn't work at all for me (validation error?), using this entitlements file:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>com.apple.developer.homekit</key>
    <true/>
    <key>com.apple.security.app-sandbox</key>
    <true/>
    <key>com.apple.security.network.client</key>
    <true/>
    <key>com.apple.security.network.server</key>
    <true/>
</dict>
</plist>

That's it for this weekend. Will revert the addition for the next release if I don't get this working before then.

[glyph]

Looking at the output of codesign --display --entitlements=- /System/Applications/Home.app suggests that there are a TON of additional entitlements that might be implicated here, particularly concerning being com.apple.homekit.private-spi-access .

All the official docs still make it clear that macOS is not supported by any of these frameworks or entitlements, only "Mac Catalyst".