Sending content

Sending content

The AP is only an API. It keeps a few text fields and a layout name per label, draws each label's screen from them, and sends it when the label polls. Anything that can make an HTTP request can be a client: a script, a web shop, a till system, home automation.

flowchart LR
    client["Your software"]
    ap["Access point<br/>stores text per label<br/>draws each screen"]
    tags["Labels"]
    client -- "HTTP + token" --> ap
    ap -- "802.15.4 radio" --> tags

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The quickest way

curl -X PUT http://openesl.local/api/tags/00000123456789A8 \
  -H "Authorization: Bearer $TOKEN" \
  -d '{"layout": "price", "fields": ["Lettmelk 1 L", "24,90", "kr 24,90/L"]}'

The label shows it at its next poll, about a minute with the default interval. The MAC is on the label's start screen and on the Dashboard.

Pick your way in

You want to	Read
Call the API from your own code	HTTP API
Use a ready-made command-line client	esl-client
Send a whole price list from Excel or your till	Price lists from CSV
Change prices at a set time, without your computer on	Scheduled prices
Show something from Home Assistant	Home Assistant
Send text to many labels by hand	Dashboard

Good to know

• Sending the same content again costs nothing: the AP sees it is unchanged and the label does not redraw.
• Each new screen costs battery. Content that changes every few minutes (a countdown, a percentage) drains it much faster than daily price changes; round the numbers.