node

OpenRFSense Node

The node software is designed to run as a daemon on remote/embedded devices, which serve as RF monitoring stations. This daemon is responsible for:

• Handling commands sent by the backend through MQTT and responding accordingly
• Showing a simple web interface exposed on localhost, easily accessible via the temporary hotspot (see openrfsense/image)

Table of contents

• OpenRFSense Node
  • Configuration
    • YAML
    • Environment variables
  • NATS
    • System statistics/metrics

Configuration

⚠️ The configuration is WIP

The config module from openrfsense/common is used. As such, configuration values are loaded from a YAML file first, then from environment variables.

YAML

See the example config.yml file for now, as the configuration is very prone to change.

Environment variables

Environment variables are defined as follows: ORFS_SECTION_SUBSECTION_KEY=value. They are loaded after any other configuration file, so they cam be used to overwrite any configuration value.

NATS

Nodes use NATS to exchange messages, under the node. root subject. Messages are encoded with JSON and relayed in NATS' own wire format. The subject structure can be generalized as follows:

• General, network-wide or broadcast messages:
  • Backend sends a request on node.$channel
  • Nodes send NATS replies on a single arbitrary/unique inbox
• Single-node requests:
  • Backend sends a request on node.$id.$channel
  • The node sends a NATS reply on an arbitrary/unique inbox

System statistics/metrics

This section will probably get moved, but it felt right to include it in this readme