Added templates to Bayesian sensor (#8408)

* Added templates to Bayesian sensor

* change quotes

* more changes

* Added raw/endraw tags

source/_components/binary_sensor.bayesian.markdown

@@ -57,10 +57,21 @@ observations:
   required: true
   type: list
   keys:
-    entity_id:
-      description: Name of the entity to monitor.
+    platform:
+      description: >
+        The supported platforms are `state`, `numeric_state`, and `template`.
+        They are modeled after their corresponding triggers for automations,
+        requiring `to_state` (for `state`), `below` and/or `above` (for `numeric_state`) and `value_template` (for `template`).
       required: true
       type: string
+    entity_id:
+      description: Name of the entity to monitor.
+      required: true (for `state` and `numeric_state`)
+      type: string
+    value_template:
+      description: Defines the template to be used.
+      required: true (for `template`)
+      type: template         
     prob_given_true:
       description: The probability of the observation occurring, given the event is `true`.
       required: true
@@ -70,17 +81,10 @@ observations:
       required: false
       type: float
       default: "`1 - prob_given_true` if `prob_given_false` is not set"
-    platform:
-      description: >
-        The only supported observation platforms are `state` and `numeric_state`,
-        which are modeled after their corresponding triggers for automations,
-        requiring `below` and/or `above` instead of `to_state`.
-      required: true
-      type: string
     to_state:
       description: The target state.
-      required: true
-      type: string
+      required: true (for `state`)
+      type: string    
 {% endconfiguration %}
 
 ## {% linkable_title Full examples %}
@@ -95,23 +99,23 @@ binary_sensor:
   prior: 0.25
   probability_threshold: 0.95
   observations:
-    - entity_id: 'sensor.living_room_motion'
+    - platform: 'state'
+      entity_id: 'sensor.living_room_motion'
       prob_given_true: 0.4
       prob_given_false: 0.2
-      platform: 'state'
       to_state: 'off'
-    - entity_id: 'sensor.basement_motion'
+    - platform: 'state'
+      entity_id: 'sensor.basement_motion'
       prob_given_true: 0.5
       prob_given_false: 0.4
-      platform: 'state'
       to_state: 'off'
-    - entity_id: 'sensor.bedroom_motion'
+    - platform: 'state'
+      entity_id: 'sensor.bedroom_motion'
       prob_given_true: 0.5
-      platform: 'state'
       to_state: 'on'
-    - entity_id: 'sun.sun'
+    - platform: 'state'
+      entity_id: 'sun.sun'
       prob_given_true: 0.7
-      platform: 'state'
       to_state: 'below_horizon'
 ```
 
@@ -126,8 +130,27 @@ binary_sensor:
   prior: 0.2
   probability_threshold: 0.9
   observations:
-    - entity_id: 'sensor.outside_air_temperature_fahrenheit'
+    - platform: 'numeric_state'
+      entity_id: 'sensor.outside_air_temperature_fahrenheit'
       prob_given_true: 0.95
-      platform: 'numeric_state'
       below: 50
 ```
+
+Finally, here's an example for `template` observation platform,
+as seen in the configuration it requires `value_template` and does not use `entity_id`.
+
+{% raw %}
+```yaml
+# Example configuration.yaml entry
+binary_sensor:
+  name: 'Paulus Home'
+  platform: 'bayesian'
+  prior: 0.5
+  probability_threshold: 0.9
+  observations:
+    - platform: template
+      value_template: >
+        {{is_state('device_tracker.paulus','not_home') and ((as_timestamp(now()) - as_timestamp(states.device_tracker.paulus.last_changed)) > 300)}}
+      prob_given_true: 0.95
+```
+{% endraw %}