So, in case anyone else wants it, here is the final full code – tested, tidied up and annotated.
Thanks to all of you for your help and to others on the forum and elsewhere on the internet who made contributions to this subject.
##----------------------------------------------------------------------------------------------------------------------
##
## Unavailable Entities Sensor
##
## 05-Feb-2024 | Andy Symons | created
##
## Credit: based loosely on https://github.com/jazzyisj/unavailable-entities-sensor/blob/main/README.md
##
## The sensor provides lists related to real devices, not internal entities, helpers, automations etc.,
## Entities with state 'unknown' are not counted, because it is possible for a device to have a sub-entity that is
## unknown while the device itself is available.
##
## The STATE simply gives the count of unavailable entities.
## The long results have to be attributes because the state cannot contain more than 255 characters:
## ATTRIBUTE 'entity_id_list' contains a list of unavailable entities using their entity ids, which may or may not have been set by the user.
## ATTRIBUTE 'entity_name_list' contains a list of unavailable entities using their friendly names as assigned by the user.
## ATTRIBUTE 'device_name_list contains a list of the devices that are unavailable, which is to say having one or more entities that are unavailable,
## using their friendly names as assigned by the user.
##
##----------------------------------------------------------------------------------------------------------------------
template:
- sensor:
name: "Unavailable Entities"
unique_id: unavailable_entities
icon: "{{ iif(states(this.entity_id)|int(-1) > 0,'mdi:alert-circle','mdi:check-circle') }}"
state_class: measurement
unit_of_measurement: entities
# The entity state is the count of unavailable entites
state: >
{{ states
| selectattr('domain','in',['binary_sensor', 'climate', 'light', 'sensor', 'switch'])
| selectattr('state', 'in', ['unavailable'])
| map(attribute='entity_id')
| unique
| list
| count
}}
# The long results have to be attributes because the state cannot contain more than 255 characters.
attributes:
## A list of unavailable entities using their entity ids (which mnay or may not have been set by the user).
entity_id_list: >-
{{ states
| selectattr('domain','in',['binary_sensor', 'climate', 'light', 'sensor', 'switch'])
| selectattr('state', 'in', ['unavailable'])
| map(attribute='entity_id')
| reject('match', 'None')
| list
| sort
| join('\n')
}}
## A list of unavailable entities using their friendly names as assigned by the user.
entity_name_list: >-
{{ states
| selectattr('domain','in',['binary_sensor', 'climate', 'light', 'sensor', 'switch'])
| selectattr('state', 'in', ['unavailable'])
| map(attribute='entity_id')
| map('state_attr', 'friendly_name')
| reject('match', 'None')
| list
| sort
| join('\n')
}}
## A list of the devices that are unavailable, using their friendly names as assigned by the user.
device_name_list: >-
{{ states
| selectattr('domain','in',['binary_sensor', 'climate', 'light', 'sensor', 'switch'])
| selectattr('state', 'in', ['unavailable'])
| map(attribute='entity_id')
| map('device_attr', 'name_by_user')
| reject('match', 'None')
| unique
| list
| sort
| join('\n')
}}
# HOW THE ATTRIBUTE TEMPLATES WORK
# -- Taking device_name_list as an example...
#
# {{ states -- all the states (entities) in the system
# | selectattr('domain','in',['binary_sensor', 'climate', etc. -- filter only the entities for real devices
# | selectattr('state', 'in', ['unavailable']) -- filter only entities that are unavailable
# | map(attribute='entity_id') -- get the entity id from the record
# | map('device_attr', 'name_by_user') -- map the entity id onto the device name
# | reject('match', 'None') -- take out names 'None' (meaning there is no name, so not a device)
# | unique -- take out duplicates (devices usually have several entities)
# | list -- make into a list (in the template sense)
# | sort -- put them in alphabetical order
# | join('\n') -- take out extraneous punctuation for a tidy output
# }}
This web page is colouring the last few lines incorrectly; it’s just comment and will be fine when you paste it into a YAML file.
If you use this sensor code, please …
I learned a lot.
.