How to fetch rest data unknown index

Configuration
1

I am trying to fetch Signal Messenger Messages.

they come like this:

[
	{
		"envelope":
			{
				"source":"APHONENUMBER",
				"sourceNumber":"APHONENUMBER",
				"sourceUuid":"SOMEUID",
				"sourceName":"SOMENAME",
				"sourceDevice":2,
				"timestamp":1746072621643,
				"serverReceivedTimestamp":1746072621400,
				"serverDeliveredTimestamp":1746072629686,
				"syncMessage":
					{
						"readMessages":
							[
								{
									"sender":"ANOTHERPHONENUMBER",
									"senderNumber":"ANOTHERPHONENUMBER",
									"senderUuid":"SOMEOTHERUID",
									"timestamp":1746041119011
								},
								{"sender":"APHONENUMBER","senderNumber":"APHONENUMBER","senderUuid":"SOMEUID","timestamp":1746041117020}
							]
					}
			},
		"account":"APHONENUMBER"
	},
	{
		"envelope":
			{
				"source":"APHONENUMBER",
				"sourceNumber":"APHONENUMBER",
				"sourceUuid":"SOMEUID",
				"sourceName":"SOMENAME",
				"sourceDevice":2,
				"timestamp":1746072623669,
				"serverReceivedTimestamp":1746072623637,
				"serverDeliveredTimestamp":1746072629687,
				"syncMessage":
					{
						"sentMessage":
							{
								"destination":"ANOTHERPHONENUMBER",
								"destinationNumber":"ANOTHERPHONENUMBER",
								"destinationUuid":"SOMEOTHERUID",
								"timestamp":1746072623669,
								"message":"hi",
								"expiresInSeconds":0,
								"viewOnce":false
							}
					}
			},
			"account":"APHONENUMBER"
	},
	{
		"envelope":
			{
				"source":"ANOTHERPHONENUMBER",
				"sourceNumber":"ANOTHERPHONENUMBER",
				"sourceUuid":"SOMEOTHERUID",
				"sourceName":"ANOTHERNAME",
				"sourceDevice":1,
				"timestamp":1746072623471,
				"serverReceivedTimestamp":1746072623948,
				"serverDeliveredTimestamp":1746072629687,
				"dataMessage":
					{
						"timestamp":1746072623471,
						"message":null,
						"expiresInSeconds":0,
						"viewOnce":false,
						"reaction":
							{
								"emoji":"šŸ‘šŸ½",
								"targetAuthor":"APHONENUMBER",
								"targetAuthorNumber":"APHONENUMBER",
								"targetAuthorUuid":"SOMEUID",
								"targetSentTimestamp":1746072623669,
								"isRemove":false
							}
					}
			},
			"account":"APHONENUMBER"
	},
	{
		"envelope":
			{
				"source":"ANOTHERPHONENUMBER",
				"sourceNumber":"ANOTHERPHONENUMBER",
				"sourceUuid":"SOMEOTHERUID",
				"sourceName":"ANOTHERNAME",
				"sourceDevice":1,
				"timestamp":1746072623465,
				"serverReceivedTimestamp":1746072623967,
				"serverDeliveredTimestamp":1746072629687,
				"receiptMessage":
					{
						"when":1746072623465,
						"isDelivery":true,
						"isRead":false,
						"isViewed":false,
						"timestamps":[1746072623669]
					}
			},
			"account":"APHONENUMBER"
	},
	{
		"envelope":
			{
				"source":"ANOTHERPHONENUMBER",
				"sourceNumber":"ANOTHERPHONENUMBER",
				"sourceUuid":"SOMEOTHERUID",
				"sourceName":"ANOTHERNAME",
				"sourceDevice":1,
				"timestamp":1746072624012,
				"serverReceivedTimestamp":1746072624080,
				"serverDeliveredTimestamp":1746072629687,
				"receiptMessage":
					{"when":1746072624012,"isDelivery":false,"isRead":true,"isViewed":false,"timestamps":[1746072623669]}},"account":"APHONENUMBER"},
	{"envelope":{"source":"ANOTHERPHONENUMBER","sourceNumber":"ANOTHERPHONENUMBER","sourceUuid":"SOMEOTHERUID","sourceName":"ANOTHERNAME","sourceDevice":1,"timestamp":1746072624144,"serverReceivedTimestamp":1746072624212,"serverDeliveredTimestamp":1746072629687,"typingMessage":{"action":"STARTED","timestamp":1746072624144}},"account":"APHONENUMBER"},
	{
		"envelope":
			{
				"source":"ANOTHERPHONENUMBER",
				"sourceNumber":"ANOTHERPHONENUMBER",
				"sourceUuid":"SOMEOTHERUID",
				"sourceName":"ANOTHERNAME",
				"sourceDevice":1,
				"timestamp":1746072624275,
				"serverReceivedTimestamp":1746072624344,
				"serverDeliveredTimestamp":1746072629687,
				"dataMessage":
					{
						"timestamp":1746072624275,
						"message":"Hi Ewald",
						"expiresInSeconds":0,
						"viewOnce":false,
						"quote":
							{
								"id":1746072623669,
								"author":"APHONENUMBER",
								"authorNumber":"APHONENUMBER",
								"authorUuid":"SOMEUID",
								"text":"hi",
								"attachments":[]
							}
					}
			},
		"account":"APHONENUMBER"
	},
	{
		"envelope":
			{
				"source":"APHONENUMBER",
				"sourceNumber":"APHONENUMBER",
				"sourceUuid":"SOMEUID",
				"sourceName":"SOMENAME",
				"sourceDevice":2,
				"timestamp":1746072624841,
				"serverReceivedTimestamp":1746072624425,
				"serverDeliveredTimestamp":1746072629687,
				"syncMessage":
					{
						"readMessages":
							[
								{
									"sender":"APHONENUMBER",
									"senderNumber":"APHONENUMBER",
									"senderUuid":"SOMEUID",
									"timestamp":1746072623669
								}
							]
					}
			},
		"account":"APHONENUMBER"
	}
]

I fetch the messages with this:

sensor:
  - platform: rest
    name: "Signal message received test"
    unique_id: signal_msg_rcv_t
    resource: http://MYIP:8080/v1/receive/MYNUMBER
    headers: 
      Content-Type: application/json
    json_attributes_path: $.[0].envelope
    json_attributes:
          - source
          - sourceName
          - timestamp
    value_template: "{{ value_json[0].envelope.dataMessage.message }}"

But as you can see I donā€™t need index 0. I need index 3&7. Because those are the ones that actually hold the received messages. The rest are receiptMessage or syncMessage.

And how to do that for json_attributes_path: $.[0].envelope

How can I determine which index to use. And potentially extract two sensor values in one call. So not two different sensors, but one sensor, two values in one go.

2

Found the answer to my first question:

value_template: >
        {% for n in value_json %}
            {% if n.envelope.dataMessage is defined and n.envelope.dataMessage.message is defined %}
                {{ n.envelope.dataMessage.message }}
            {% endif %}
        {% endfor %}

To get the json_attributes_path: $..[?(@.dataMessage)]

But what if I have received multiple messages?

5

Hi Emily,

Thank you so much for your help! Much appreciated.

This is what worsk for me now:

{% set msgs = value_json | selectattr("envelope.dataMessage") | list %}
{% set msg = msgs | selectattr("envelope.dataMessage.message", "string" ) | list %}
{% if msg |length > 0 %}
        {{ msg[0].envelope.dataMessage.message }}
{% else %}
          {{ states('sensor.signal_msg_rcv_2') }}
{% endif %}

Somehow selectattr(ā€œenvelope.dataMessage.messageā€) returns an empty list, but now if I do it in two steps like this, that works.

Thanmk you once again!