Susi
Susi (SUsi is not SnIps) is a replacement for the Snips home assistant ecosystem. It follows mainly the same architecture as Snips (with a MQTT broker as central unit and MQTT messages exchanged between the components). Consequently most native Snips skills will run with Susi as well but without the need of the (no longer available) Snips console.
Susi is build as a modular system as a collection of of daemons (hotword detection, record, speech to text, intent recognion, play, skill managment). Most daemons are lightweight bash scripts responsible for communication with other daemons via MQTT messages. The actual workers for the respective functionality can be configured separately and hence can be replaced easily.
Main components
All components run standalone on one or more satellites of the installation and communicate with each other and with the session manager via MQTT.
A default session includes the following components and steps:
MQTT broker
A mosquitto MQTT broker ist started by the susi service. Hostname, port, login and password must be configured in the /etc/susi.toml files of all satellites.
Hotword detection
An hotword detector must run on all sattelites, on which voice commands need to be detected. The detector program must publish a MQTT-topic with topic hermes/hotword/detected and the siteId as payload.
Record service
A record service must run on all sattelites, on which voice commands need to be detected. It subscribes to the MQTT-topic hermes/asr/startListening. If a message with the correct siteId is received, it records a voice command and publishes a message with topic susi/asr/audioCaptured and the base64-encoded recording in flac-format. The payload id matches the id of the request.
Speech-to-text service
A speech-to-text service runs only once for an installation. It subscribes to the MQTT-topic susi/asr/transscribe. If a message is received, it extracts text from the audio and publishes a message with topic hermes/asr/textCaptured with the transcribed text as payload. The payload id matches the id of the request.
Natural language understanding
A NLU service runs only once for an installation. It subscribes to the MQTT-topic hermes/nlu/query. If a message is received, it extracts text from the audio and publishes a message with topic hermes/nlu/intentParsed with the recognised skill intent as payload or hermes/nlu/intentNotRecognized. The payload id matches the id of the request.
Session manager
The session manager runs only once for an installation. It orchestrates session sequences (like the one described above) starts, queues and ends sessions and publishes final intents.
Skill manager
Skills are standalone programs that may run on any computers of a Susi installation. Each skill must subscribe to the topics of its intents (such as /hermes/intent/andreasdominik:LightOn) and execute the requested actions.
Susi's skill manager makes sure, that all skills located in the skills directory are running (all skills with name pattern action-... wil be started with the susi service and restarted if they crash).
Play service
A play service must run on all sattelites, on which audio output is required. It subscribes to the MQTT-topic susi/playserver/request. If a message with the correct siteId is received, it playsteh audio included in the payload and publishes a message with topic susi/playserver/playFinished. The payload id matches the id of the request.
Text-to-speech service
A text-to-speech service runs only once for an installation. It subscribes to the MQTT-topic susi/tts/request. If a message is received, it geberates an aodio of the text and publishes it as payload of a message with topic susi/tts/audio. The payload id matches the id of the request.
Skills
As all main MQTT topics are comaptible with the respective Snips.ai-topics, all Snips-skills shold run with Susi. However it is recommended, not to use Snips' Hermes framework for Python for skill development. Instead, the Julia-framework ADoSnipsQnD supports writing skills (for Snips and Susi) in the modern and fast programming language Julia and makes it simple to develop skills with multilanguage support and extensive user interaction.
Currently supported and tested skills include:
- ADoSnipsLights
- ADoSnipsKodi
- ADoSnipsTVViera
- ADoSnipsWakeup
- ADoSnipsRollerShutter
- ADoSnipsIrrigation
- ADoSnipsDoNotListen
- ADoSnipsAutomation
- SusiTime