I really like FSMs, I find they make it much easier to reason about more complex automations. So I created a custom component that creates sensors backed by the transitions library.
Configuration
Currently configured using a JSON schema that is very close to Node Red’s
Finite State Machine
A special timeout trigger is supported for time-based automatic transitions.
Example Config
Tracks the state of a dryer starting up, running, and stopping. The automation sends above,
below, and middle triggers based on the dryer’s power consumption. Automatic transitions
happen from STARTING to RUNNING after 1 second, from STOPPING to DONE after 2 minutes, and
from DONE to IDLE after 15 seconds.
{
"state": {
"status": "IDLE"
},
"transitions": {
"IDLE": {
"above": "STARTING"
},
"STARTING": {
"timeout": { "after": 1, "to": "RUNNING" },
"below": "IDLE"
},
"RUNNING": {
"below": "STOPPING"
},
"STOPPING": {
"timeout": { "after": 120, "to": "DONE" },
"above": "RUNNING",
"middle": "RUNNING"
},
"DONE": {
"timeout": { "after": 15, "to": "IDLE" }
}
}
}
Example Automation
Uses the FSM above, configured as sensor.dryer_state. Triggers are a faux drier power meter
input_number.dryer_power and the FSM sensor when it transitions to the DONE state where
we want to take an action.
The automation uses the state_machine.trigger service to send triggers to the sensor.dryer_state
state machine entity based on the dryer’s current power.
When the state machine eventually cycles to DONE that trigger results in a notification being sent.
alias: Drier Notifier
description: ""
trigger:
- platform: state
entity_id:
- input_number.dryer_power
- platform: state
entity_id:
- sensor.dryer_state
to: DONE
id: DRYER_DONE
condition: []
action:
- choose:
- conditions:
- condition: trigger
id: DRYER_DONE
sequence:
- service: notify.notify
data:
message: Drier Is Done
default:
- choose:
- conditions:
- condition: numeric_state
entity_id: input_number.dryer_power
above: 50
sequence:
- service: state_machine.trigger
data:
trigger: above
target:
entity_id: sensor.dryer_state
- conditions:
- condition: numeric_state
entity_id: input_number.dryer_power
below: 15
sequence:
- service: state_machine.trigger
data:
trigger: below
target:
entity_id: sensor.dryer_state
default:
- service: state_machine.trigger
data:
trigger: middle
target:
entity_id: sensor.dryer_state
mode: queued
max: 10