config.go

package main

import (
	"fmt"
	"os"
	"time"

	flag "github.com/spf13/pflag"
	"github.com/vetinari/brickd_exporter/mqtt"
	"gopkg.in/yaml.v2"
)

const (
	defaultListenAddress = ":9639"
	defaultMetricsPath   = "/metrics"
)

type LocalConfig struct {
	Listen    ListenConfig    `yaml:"listen"`
	Brickd    BrickdConfig    `yaml:"brickd"`
	Collector CollectorConfig `yaml:"collector"`
	MQTT      *mqtt.MQTT      `yaml:"mqtt"`
}

type ListenConfig struct {
	Address     string `yaml:"address"`
	MetricsPath string `yaml:"metrics_path"`
}

type BrickdConfig struct {
	Address  string `yaml:"address"`
	User     string `yaml:"user"`
	Password string `yaml:"password"`
}

type CollectorConfig struct {
	LogLevel       string                                  `yaml:"log_level"`
	CallbackPeriod time.Duration                           `yaml:"callback_period"`
	IgnoredUIDs    []string                                `yaml:"ignored_uids"`
	Labels         map[string]string                       `yaml:"labels"`
	SensorLabels   map[string]map[string]map[string]string `yaml:"sensor_labels"`
	LEDStatus      string                                  `yaml:"led_status"`
	Expire         time.Duration                           `yaml:"expire_period"`
}

func parseConfig() (*LocalConfig, error) {
	var configFile = flag.String("config.file", "", "Path to configuration file.")
	flag.Parse()

	if *configFile == "" {
		return defaultConfig()
	}

	file, err := os.Open(*configFile)
	if err != nil {
		return nil, fmt.Errorf("can not open config file: %s", err)
	}

	config := &LocalConfig{}
	if err := yaml.NewDecoder(file).Decode(config); err != nil {
		return nil, fmt.Errorf("error decoding config file %q: %s", *configFile, err)
	}

	return config, nil
}

func defaultConfig() (*LocalConfig, error) {
	return &LocalConfig{
		Brickd: BrickdConfig{
			Address: "localhost:4223",
		},
		Listen: ListenConfig{
			Address:     defaultListenAddress,
			MetricsPath: defaultMetricsPath,
		},
		Collector: CollectorConfig{
			LogLevel:       "info",
			CallbackPeriod: 10 * time.Second,
			Expire:         0,
			LEDStatus:      "on",
		},
		MQTT: &mqtt.MQTT{
			Enabled: false,
			Topic:   "brickd/",
			HomeAssistant: mqtt.HomeAssistant{
				Enabled:       false,
				DiscoveryBase: "homeassistant/",
				Interval:      5 * time.Minute,
			},
		},
	}, nil
}