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The Alert block can notify the user or external applications when specified conditions are triggered:

Alert Block

Left hand side Input:

  • Input 1
  • ...
  • Input 8

The Alert block can monitor up to eight input streams, and generate notifications as display messages, HTTP requests, audio alerts or process calls. It can also log any generated alert and optionally record data when an alert is triggered:

Alert Settings

Individual alerts are created or removed using the hamburger menus on the right hand side of the configuration menu:

Alert Creation


Once created, an alert can be given a name and assigned to any input stream. Then a trigger condition needs to be specified. Alerts can either react to any of the standard condition flags (usually coming from a Spectrum Condition block), or simply react to incoming data on the selected stream. The "Edge" settings defines when the alert is triggered: "Rising" reacts to the flag changing from inactive to active, "Falling" from active to inactive, "Both" to any change and "Level" triggers as long as the condition is active.

The most basic alert is to simply display a text in its graph area, specified by "Alert Title" and "Alert Message":


With the "Record Data" option the data packet that triggered the alert can be stored as JSON when the alert is triggered (contents depend on the stream type). if the file already exists, the data is appended, not overwritten. Please note that this is not a regular data recording and can not be processed by the File Reader or File Source blocks.

More complex alerts can be built using the "Alert Process" setting, which will execute the specified program when the alert is triggered. This can optionally be called with a fixed set of commandline parameters, and/or receive the data packet that triggered the alert as JSON data on its standard input.

Alternatively the Alert block can generate a HTTP request to an external service by specifying the "Alert HTTP", "Alert URL" and "Alert Body" (using Key=Value syntax) settings accordingly. If the trigger sample should be included in the request, the "post data" method must be used.

Last but not least the alert can be logged in the graph area of the Alert block, and optionally also recorded in a persistent log file.

Typical Mission:

Alert Typical Mission

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