dhcgn/hm2mqtt

package shared

// TODO with Go 1.16 should use FS for testing

import (
    "encoding/json"
    "io/ioutil"
    "log"
    "os"
    "path/filepath"
)

// Config is the instance of the actual Configuration
var Config Configuration

// ConfigFilePath is the path to the config file
var ConfigFilePath string

// Configuration is the config which is necessarily to run hm2mqtt
type Configuration struct {
    // ListenerPort is the own port which hm2mqtt is listening to
    ListenerPort int
    // InterfaceID is an ID used for RPC calls
    InterfaceID int
    // HomematicURL the url points to homematic rpc
    HomematicURL string
    // BrokerURL the url points to a mqtt broker
    BrokerURL string
    // Retain mqtt messages
    Retain bool
}

// UpdateConfiguration save new config to disk
func UpdateConfiguration(c Configuration) {
    Config = c

    f, _ := os.Create(ConfigFilePath)
    defer f.Close()
    j, _ := json.MarshalIndent(c, "", "   ")
    f.Write(j)
    f.Sync()
}

// ReadConfig read config from disk
func ReadConfig(overriddenPath string) *Configuration {
    dir, _ := filepath.Abs(filepath.Dir(os.Args[0]))
    ConfigFilePath = filepath.Join(dir, "config.json")
    configSamplePath := filepath.Join(dir, "config.sample.json")

    if overriddenPath != "" {
        ConfigFilePath = overriddenPath
        configSamplePath = overriddenPath
    }

    if _, err := os.Stat(configSamplePath); os.IsNotExist(err) {
        newConfig := Configuration{
            ListenerPort: 8777,
            InterfaceID:  2,
            HomematicURL: "http://127.0.0.1:2001/",
            BrokerURL:    "tcp://192.168.10.31:1883",
        }
        f, _ := os.Create(configSamplePath)
        defer f.Close()
        j, _ := json.MarshalIndent(newConfig, "", "   ")
        f.Write(j)
        f.Sync()
    }

    if _, err := os.Stat(ConfigFilePath); os.IsNotExist(err) {
        log.Fatalf("No config at %v", ConfigFilePath)
    }

    dat, _ := ioutil.ReadFile(ConfigFilePath)
    c := Configuration{}
    json.Unmarshal(dat, &c)

    Config = c
    return &c
}