gbcsdpd

gbcsdpd Daemon

gbcsdpd daemon is a single go binary with a single configuration file that listens for sensors BLE Advertisements via BlueZ D-Bus API and publishes them to configured sinks. MQTT sink is the main sink, but there is also Cloud Pub/Sub and a useful for debugging stdout sink.

Building

This repository is using Bazel but it also supports building binaries using the standard go build command, so both:

bazel build //cmd/gbcsdpd

and

go build ./cmd/gbcsdpd

work.

Usage

Run the binary and it should start printing measurements on standard output.

$ ./gbcsdpd
[default-sink] 00:11:22:33:44:55 = 23.96°C, 43.17%, 963.69hPa, 2.38V
[default-sink] aa:bb:cc:dd:ee:ff = 24.55°C, 41.74%, 963.15hPa, 2.51V
[default-sink] 00:11:22:33:44:55 = 23.96°C, 43.17%, 963.69hPa, 2.39V
[default-sink] aa:bb:cc:dd:ee:ff = 24.55°C, 41.76%, 963.17hPa, 2.51V

gbcsdpd needs to be configured to be more useful. Specify path co configuration file on -config flag. Configuration file is using TOML format.

The default configuration for the default behavior above looks like:

adapter = "hci0"  # this is the default value that you can omit

[[sinks.stdout]]  # this sink is only added when there aren't any other defined
name = "default-sink"

and you can start gbcsdpd and load it: ./gbcsdpd -config config.toml.

Configuration

The only top-level setting is the Bluetooth adapter name and the rest of the configuration consists of a list of sinks to push publications to. There can be multiple sinks of the same and different types in the same configuration. There are currently 3 types of sinks implemented:

• Stdout: useful for debugging, prints measurements on stdout.
• MQTT: generic MQTT target allowing to specify username, password, topic, format, etc.
• Cloud Pub/Sub: sink pushing to Google Cloud Pub/Sub topic.

Data to MQTT servers is published as gbcsdpd.api.v1.MeasurementsPublication Protobuf messages serialized to JSON or binary format (format config option on MQTT sink).

The reference and documentation for all available configuration options is in the pkg/config/config_format.go file. fConfig type is the root of configuration.

To see how does an example configuration with a lot of options set looks like see pkg/config/testdata/test1/config.toml file.

Running as a service

The init/ directory in this repository contains instructions and configuration templates for systemd and OpenWrt init systems.

Cross-compilation

Both Bazel and standard go distribution support cross-compilation to different architectures.

Bazel

See documention at https://github.com/bazelbuild/rules_go#how-do-i-cross-compile

For example arm+linux:

bazel build --platforms=@io_bazel_rules_go//go/toolchain:linux_arm //cmd/gbcsdpd

Go Distribution

See $GOOS and $GOARCH documentation at https://golang.org/doc/install/source#environment.

For example arm+linux:

GOOS=linux GOARCH=arm go build ./cmd/gbcsdpd