Use of template in rest sensor - payload

Configuration
1

Hi,
I’m working on a rest sensor which does a POST request and requires a start and end date.
I read in the official docs that only a string is allowed for the payload.
is there no other way to use a template in there?

What I’m trying to achieve but doesn’t work unfortunately:

- platform: rest
  authentication: basic
  username: admin
  password: !secret mysecret
  resource_template: "https://mysite.com/v1/json_data"
  payload: >
    { 
      "startDate" : "2024-02-01",
      "endDate" : "{{ now().date() - timedelta(days=1) }}" 
    }
  method: POST
  name: "test api"
  unique_id: test_api
  value_template: 'Active'
  scan_interval: 300

this way I’m able to retrieve data from yesterday automatically, otherwise I have to change the endDate everything in the rest sensor.

Thanks

3

What does the response look like without dates? Can you create a template sensor from that sensor that extracts what you wish? I use a rest sensor payload like this:

payload: '{"KEYLIST": [{"CODESET": {{ codeset | int }},"CODE": {{ code | int }},"ACTION":"KEYPRESS"}]}'

Watching your single/double quotes and putting it all in a string (of JSON).

4

I’ve answered my own question. it’s possible to use “payload_template” instead of “payload”!
But it’s not documented on the official docs yet.

5

It isn’t in an official release yet. It’s in 2024.6.

1 Like
6

Does anyone know if “payload_template” ever made it into an official release as I can’t see it in the 2024.6 release notes?

7
8

OK, thanks. I’ve now implemented ‘payload_template’ in a POST command to a remote server but am having problems - I’m clearly missing something / making a simple mistake and would massively appreciate some assistance.

I have successfully used ‘payload_template’ with the following code (plus multiple other derivatives that all use a fixed text string like below):

payload_template: >-
{% set fr_text = '{ \"text\" : [\"' + 'A test string' + '\"], \"target_lang\" : \"EN\" }' %}
{{ fr_text }}

… but when I substitute ‘A test string’ with the state value of a sensor the payload is no longer considered valid by the remote server.

payload_template: >-
{% set fr_text = '{ \"text\" : [\"' +  states('sensor.sourcetextsensor')  + '\"], \"target_lang\" : \"EN\" }' %}
{{ fr_text }}

Unfortunately the remote server doesn’t provide any error response so I can’t easily debug. I have however tried using the above code (and multiple other versions) in ‘Developer Tools / Template’ and frustratingly they all appear to work fine and return exactly the same output as when using the static text.

Any ideas would be greatly appreciated.

9

Indent your template in relation to the yaml field it’s in.

Also you can just make a normal output and use | to_json

10

Apologies, that was just bad formatting when I copy / pasted the code in the post as it is already indented:

payload_template: >-
  {% set fr_text = '{ \"text\" : [\"' +  states('sensor.sourcetextsensor')  + '\"], \"target_lang\" : \"EN\" }' %}
  {{ fr_text }}

I did also try the to_json idea but again hit the same issue, here’s my code:

payload_template: >-      
  {% set fr_text = '{ \"text\" : [\"' +  states('sensor.sourcetextsensor')  + '\"], \"target_lang\" : \"EN\" }' %}
  stringified object: {{ fr_text }}
  object|to_json: {{ fr_text|to_json) }}
11 
payload_template: >
  {{ {'text': [states('sensor.sourcetextsensor')], 'target_lang': 'EN'} | to_json }}