th7/config/config.go

package config

import (
	"errors"
	"fmt"
	"strings"
	"th7/data/config"
	"th7/data/thermocouple"

	"github.com/spf13/viper"
)

var (
	ErrConfigBadThermocoupleType = errors.New("unrecognised thermocouple type")
)

var (
	thermocoupleTypes = map[string]thermocouple.Type{
		"B": thermocouple.B,
		"E": thermocouple.E,
		"J": thermocouple.J,
		"K": thermocouple.K,
		"N": thermocouple.N,
		"R": thermocouple.R,
		"S": thermocouple.S,
		"T": thermocouple.T,
		"U": thermocouple.None, // for uV measurements
	}
)

func getThermocoupleType(t string) (thermocouple.Type, error) {
	t = strings.ToUpper(t)
	if val, ok := thermocoupleTypes[t]; ok {
		return val, nil
	} else {
		return thermocouple.None, ErrConfigBadThermocoupleType
	}
}

func Load() (config.Config, error) {

	var cfg config.Config
	var err error

	v := viper.New()
	v.AddConfigPath(".")
	v.SetConfigFile("config.toml")

	err = v.ReadInConfig()
	if err != nil {
		return cfg, err
	}

	SetDefaultConfig(v)

	cfg.Board.Port = v.GetInt("TH7.port")
	cfg.Board.Cache = v.GetBool("TH7.cache")
	cfg.Board.Led = v.GetBool("TH7.LED")
	cfg.Board.Logfreq = v.GetInt("DB.freq")
	cfg.Board.Debug = v.GetBool("TH7.debug")
	cfg.Board.NoLogging = v.GetBool("TH7.nolog")

	cfg.Channels = make([]config.Channel, 0)

	for i := 1; i < 8; i++ {
		var c config.Channel
		var tc thermocouple.Type
		var head = fmt.Sprintf("Channel_%d", i)

		if v.GetString(head+".type") == "NOTSET" {
			continue
		}

		c.Id = i
		c.Gain = v.GetFloat64(head + ".gain")
		c.Offset = v.GetFloat64(head + ".offset")

		tc, err := getThermocoupleType(v.GetString(head + ".type"))
		if err != nil {
			fmt.Printf("%s.type=%s\n", head, v.GetString(head+ ".type"))
			return cfg, err
		}

		c.Thermo = tc
		c.Filter.SampleSize = v.GetInt(head + ".filter.samples")
		c.Filter.Type = v.GetInt(head + ".filter.type")

		cfg.Channels = append(cfg.Channels, c)
	}

	cfg.DB = v.GetStringMap("DB")

	return cfg, nil
}