metricq-source-cmd

A simple MetricQ source that executes a set of commands that return floating point numbers and sends them as metrics.

This source is more a proof of concept than a production-ready thing for the following considerations. There also is no proper error handling yet.

Security considerations

This source allows full code execution for anyone who:

• can manipulate the source configuration, or
• knows the source token and has permission to send to it RabbitMQ in the direct exchange

You should run it with limited privileges only!

Performance considerations

The commands are executed synchronously in a single thread. Using slow or many commands may block the whole source and cause connection issues.

Configuration

Here's an example configuration.

{
  "_id": "source-cmd",
  "metrics": {
    "localhost.random": {
      "command": "/bin/bash -c 'echo $RANDOM'",
      "unit": "",
      "interval": "500ms"
    },
    "localhost.date": {
      "command": "date +%s",
      "unit": "s",
      "interval": "1s"
    },
    "localhost.load": {
      "command": "bash -c 'uptime | grep -Eo [0-9.]+$'",
      "unit": "",
      "interval": "2s"
    }
  }
}

The source supports dynamic reconfiguration. When reconfiguring, all timers are restarted, including existing unchanged metrics.