SmartMeter

A .NET-based server application that reads energy data from smart meters via the Smart Message Language (SML) protocol and publishes the values over MQTT. It runs as a systemd daemon on Linux and connects to the meter through a serial optical coupler (e.g. /dev/ttyUSB0).

Features

• SML Protocol Parser -- streaming detector and parser for the Smart Message Language protocol, available as a standalone NuGet package
• MQTT Publishing -- forwards meter readings (purchased/sold energy, current power, grid balance) to an MQTT broker with configurable topics
• Linux Daemon -- runs as a systemd service under a dedicated user with automatic service registration
• CLI Tool -- command-line interface (smc) for diagnostics and manual data retrieval

Project Structure

Project	Description
CreativeCoders.SmartMessageLanguage	SML framing, TLV parsing, CRC validation, OBIS value extraction
CreativeCoders.SmartMeter.Core	Serial port abstraction and configuration options
CreativeCoders.SmartMeter.DataProcessing	Value processing pipeline and MQTT publisher
CreativeCoders.SmartMeter.Server.Core	Server logic and daemon host builder
CreativeCoders.SmartMeter.Server.Linux	Linux systemd daemon entry point
CreativeCoders.SmartMeter.Cli	CLI tool for manual interaction

Prerequisites

• .NET 10 SDK (for building from source)
• .NET 10 Runtime (on the target Linux machine)
• A smart meter with an SML-compatible infrared interface
• An optical reading head (IR coupler) connected via USB serial (e.g. /dev/ttyUSB0)
• An MQTT broker (e.g. Mosquitto)

Building

./build.sh

Or using the .NET CLI directly:

dotnet build
dotnet test

Linux Server Installation

The recommended way to install or update the SmartMeter server on Linux is by using the provided install-smartmeter.sh script. It downloads the distribution package, extracts it, and runs the bundled installer.

Quick Install (Latest Release)

Download and run the installer in one step:

curl -fsSL https://raw.githubusercontent.com/CreativeCodersTeam/SmartMeter/main/install-smartmeter.sh -o install-smartmeter.sh
chmod +x install-smartmeter.sh
./install-smartmeter.sh

This will:

1. Fetch the latest stable release from GitHub
2. Download the SmartMeter.Server.Linux.tar.gz asset
3. Extract and run the bundled install.sh with sudo

Install from CI Build

To install from the latest successful CI build instead of a release (requires the GitHub CLI with authentication):

./install-smartmeter.sh --workflows main.yml

Non-Interactive Install

Skip the confirmation prompt with -y:

./install-smartmeter.sh -y

Required Tools

Tool	Required for
curl	Downloading the archive
tar	Extracting the package
jq	Parsing GitHub API responses
sudo	Running the privileged installer
gh	Only when using --workflows

What the Installer Does

The bundled install.sh performs the following steps:

1. Stops and disables the existing smartmeter-server systemd service (if running)
2. Backs up the current installation at /opt/smartmetersrv to /opt/smartmetersrv.bak
3. Copies the new files to /opt/smartmetersrv
4. Creates a dedicated smartmeter-user system user (if it doesn't exist) and adds it to the dialout group for serial port access
5. Sets file ownership to smartmeter-user
6. Registers and starts the systemd service via dotnet smartmetersrv.dll --install

Updating

To update an existing installation, simply run install-smartmeter.sh again. The installer automatically backs up the previous installation before deploying the new version.

./install-smartmeter.sh

Tip

After an update, check that the service is running correctly:

sudo systemctl status smartmeter-server
sudo journalctl -u smartmeter-server -f

Service Management

Once installed, the server runs as a systemd service:

# Check service status
sudo systemctl status smartmeter-server

# Stop the service
sudo systemctl stop smartmeter-server

# Start the service
sudo systemctl start smartmeter-server

# View logs
sudo journalctl -u smartmeter-server -f

Installation Paths

Path	Description
/opt/smartmetersrv	Application directory
/opt/smartmetersrv.bak	Backup of the previous installation

Configuration

The server reads its configuration at startup. Key options include:

Option	Default	Description
PortName	/dev/ttyUSB0	Serial port device path for the optical coupler
MqttServer	--	URI of the MQTT broker
MqttClientName	SmartMeterClient	MQTT client identifier
MqttTopicTemplate	smartmeter/values/{0}	Topic template ({0} is replaced by the value type)

Published MQTT Values

The server publishes the following meter values:

Value	Description
TotalPurchasedEnergy	Cumulative energy purchased from the grid
TotalSoldEnergy	Cumulative energy sold to the grid
CurrentPurchasingPower	Current power being drawn
CurrentSellingPower	Current power being fed in
GridPowerBalance	Net power balance