Start/Stop Button to read sensors

Hi, I want to have a button to start reading from a mqtt node. Some examples?

The MQTT in node will send a message every time someone writes to the MQTT topic you subscribed to, you can't disable it from inside a flow (though you can from inside the editor, but that's probably not what you intend).

So you have build some kind of gate, using a switch node and a context variable, like in this example from the cookbook. https://cookbook.nodered.org/basic/route-on-context
You can then set the state of the context variable using Dashboard buttons, the switch node will allow/deny messages depending on the state of that variable.

Or, alternatively, have a look at the gate node:

+1 for the simple-gate node, it is perfect for this type of use case, blocking or allowing the mqtt messages through as desired.

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