Last Updated or created 2024-01-14

Posted because I could not find a good example on the interwebs.

Below creates a virtual HA button which toggles a blinking led.
(button and variables are called eprint for another function, change to something meaningful. )

Home Assistant virtual mqtt switch (configuration.yml)

See switch part

mqtt:
 light:    
  - name: "KitchenOutside"
    payload_on: "99"
    payload_off: "0"
    unique_id: "KitchenOutside"
    brightness_scale: "99"
    brightness_state_topic: ha433/kitchenoutside/brightcontrol
    brightness_command_topic: ha433/kitchenoutside/brightcontrol
    state_topic: ha433/kitchenoutside/brightcontrol
    command_topic: ha433/kitchenoutside/control
    optimistic: false
    on_command_type: brightness
#-----8<-------------snip ########### EXAMPLES light and sensor
 sensor:
  - name: "LivingTemperature"
    state_topic: "home/8461/payload"
    unit_of_measurement: "°C"
    value_template: "{{ value_json.svalue1 }}"
  - name: "LivingHumidity"
    state_topic: "home/8461/payload"
    unit_of_measurement: "%"
    value_template: "{{ value_json.svalue2 }}"
#--------8<--- snip ################################ ONLY PART BELOW NEEDED 
 switch:
    unique_id: esphome_switch
    name: "Esp Home Switch"
    state_topic: "esphome/eprint/tmpstate"
    command_topic: "esphome/eprint/state"
    payload_on: "ON"
    payload_off: "OFF"
    state_on: "ON"
    state_off: "OFF"
    optimistic: false
    qos: 0
    retain: true

ESP Home config for a ESP32

esphome:
  name: lolin32litemqttled
  friendly_name: lolin32litemqttled

esp32:
  board: esp32dev
  framework:
    type: arduino

# Enable logging
logger:

# Enable Home Assistant API
api:
  encryption:
    key: "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx="

ota:
  password: "xxxxxxxxxxxxxxxxxxxxxxxx"

wifi:
  ssid: !secret wifi_ssid
  password: !secret wifi_password

  # Enable fallback hotspot (captive portal) in case wifi connection fails
  ap:
    ssid: "Lolin32Litemqttled"
    password: "xxxxxxxxxxxxxxxxxxx"

captive_portal:
    
switch:
  - platform: gpio
    pin:
      number: 22
      mode: output
    id: blueLED
  - platform: template
    name: "eprint"
    id: eprint_enable
    optimistic: on

interval:
  - interval: 1000ms
    then:
      if:
        condition:
          switch.is_on: eprint_enable
        then:
          - switch.toggle: blueLED

mqtt:
  broker: 192.168.1.2
  on_message:
  - topic: esphome/eprint/state
    qos: 0
    payload: "OFF"
    then:
      - switch.turn_off: eprint_enable
  - topic: esphome/eprint/state
    qos: 0
    payload: "ON"
    then:
      - switch.turn_off: eprint_enable