Wiesemann & Theis GmbH

Networking, sensors and interface technology for industry, office and IT

Tutorial:

Web Thermometer sends push notifications via ntfy.sh

Manual: Report limit violations to a cell phone



ntfy.sh is a public messaging service. It is topic-oriented, i.e. notifications are sent by specifying unique topic names. To receive notifications, the relevant topic names must be subscribed.

These are not closed groups, rather anyone knowing the name of the topic has access to the notifications sent there.

You can download the app from the usual providers (Google Play, App-Store), but there is also access from your web browser at ntfy.sh.

http request sends a push notification to a smart phone and browser

Screenshot: htfy.sh menu

Open the web app at ntfy.sh in your browser. Clicking on + Subscribe topic opens a dialog in which you can enter the topic name you would like to subscribe to. This also creates the topic. Enter a unique name (e.g. WEBIO-123456). Pressing SUBSCRIBE subscribes you to notifications under this topic.

The procedure is identical in the mobile app with Android and Apple.

 


Screenshot: IP address menu

As soon as the topic you created is subscribed, configure sending of the notification in your Web Thermometer. Enter the IP address of the Web Thermometer in the browser and log in to the web interface with administrator rights. In the menu click on Alarms/Messages and there on Add.

 


An input screen appears for alarm configuration. First enable the new alarm and assign an appropriate name. As the trigger select Temperature and enter the permissible high and low limits.

Screenshot: Creation an action


It is also possible to set hysteresis, a change rate, a delay time as well as repeating of the alarm (once or cyclical).


Screenshot: HTTPS request setting

Further below select HTTP Request. Now the form expands and you are granted access to the associated parameters. You set the request method here at POST. The field HTTP(S) request (complete URL) as well as HTTPS(S) request clear message (complete URL) contains the ntfy.sh URL for your topic. Everything behind https://ntfy.sh/ represents the name of your topic. In the Payload field write the alarm message, and Clear Payload generates the caution message. Clicking on Apply confirms the alarm.


When the set temperature limits are violated or when the measured value returns to the tolerance range, a message is issued:

Screenshot: Push notification on the smart phone


Placeholders in the message text also allow you to insert dynamic variables such as the current measurement values. A <T1> in the message text is replaced in the output by the current temperature. This is a way to enlarge the information content of the sent messages. An exact list of the available placeholders can be found in the manual for the device.


Product overview: Web Thermometer

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