Hassmic is an Android application and Home Assistant designed to run on devices acting as Home Assistant voice assistant satellites.
It is currently in active development and probably has lots of bugs. Some highlights:
- Automatically starting on Android 12+ fails in an annoying way: the service auto-starts, but can't access the microphone. This is a security feature added to Android that I don't have a great solution for (no auto-start services can access the microphone unless they also start a UI).
- There's not really a "UI" to speak of. Opening the app gives some diagnostic information and a single toggle switch. You must enable running in the background, since that's where all the work happens. If running in the background isn't enabled, the app does nothing.
This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.
This project is built on React Native and uses a substantial amount of native code. Vestiges of expo infrastructure still exist, but expo commands won't work.
To build an APK use,
cd android
./gradlew assembleRelease
The built APK will be at android/app/build/outputs/apk/release/app-release.apk
You can also use installRelease instead of assembleRelease to install the
built package to a device connected via adb.
The HassMic client and server communicate using a slightly strange paradigm
based on protocol buffers (defined in the proto/ directory). The server sends
ServerMessage messages to the client, and the client sends ClientMessages
to the server. Because of a strange bug that I never quite got to the bottom of
with sending raw binary data back and forth, these protos are marshalled to
their binary forms and then base64-encoded, and sent over the wire as
newline-separated strings. There is no handshaking involved; client messages and
server messages are handled by separate threads on both ends. The client also
sends a periodic ping to let the server know it's still connected, even if
it's not sending audio data.
The protocol name Cheyenne is an outdated pun -- in early versions of Hassmic,
the protocol was based around the core of the Wyoming protocol. It has since
been rewritten and no longer resembles Wyoming, but for the moment the name
persists.