Initial commit

server/config/config.go

@@ -0,0 +1,189 @@
+package config
+
+import (
+	"fmt"
+	"github.com/BurntSushi/toml"
+	"os"
+	"path/filepath"
+	"reflect"
+	"strconv"
+	"strings"
+)
+
+var globConfig *Config
+
+type Config struct {
+	Profile struct {
+		Dir     string `toml:"Dir"`
+		Default struct {
+			Password           string `toml:"Password"`
+			NetworkMode        int    `toml:"NetworkMode"`
+			Configurable       bool   `toml:"Configurable"`
+			RunLevel           int    `toml:"RunLevel"`
+			StartupInformation bool   `toml:"StartupInformation"`
+			ExitAfter          string `toml:"ExitAfter"`
+			KeepOnExit         bool   `toml:"KeepOnExit"`
+		} `toml:"default"`
+		Dynamic struct {
+			Enable             bool   `toml:"Enable"`
+			Password           string `toml:"Password"`
+			NetworkMode        int    `toml:"NetworkMode"`
+			Configurable       bool   `toml:"Configurable"`
+			RunLevel           int    `toml:"RunLevel"`
+			StartupInformation bool   `toml:"StartupInformation"`
+			ExitAfter          string `toml:"ExitAfter"`
+			KeepOnExit         bool   `toml:"KeepOnExit"`
+		} `toml:"dynamic"`
+	} `toml:"profile"`
+	Api struct {
+		Port      uint16 `toml:"Port"`
+		Configure struct {
+			Binary string `toml:"Binary"`
+			Man    string `toml:"Man"`
+		} `toml:"configure"`
+	} `toml:"api"`
+	SSH struct {
+		Port       uint16 `toml:"Port"`
+		Keyfile    string `toml:"Keyfile"`
+		Passphrase string `toml:"Passphrase"`
+	} `toml:"ssh"`
+	Database struct {
+		Sqlite3File string `toml:"Sqlite3File"`
+	} `toml:"Database"`
+	Network struct {
+		Default struct {
+			Subnet string `toml:"Subnet"`
+		} `toml:"default"`
+		Isolate struct {
+			Subnet string `toml:"Subnet"`
+		} `toml:"isolate"`
+	} `toml:"network"`
+	Logging struct {
+		Level         string `toml:"Level"`
+		OutputFile    string `toml:"OutputFile"`
+		ErrorFile     string `toml:"ErrorFile"`
+		ConsoleOutput bool   `toml:"ConsoleOutput"`
+		ConsoleError  bool   `toml:"ConsoleError"`
+	} `toml:"logging"`
+}
+
+func InitConfig(includeEnv bool) (*Config, error) {
+	configFiles := []string{
+		"./docker4ssh.conf",
+		"~/.docker4ssh",
+		"~/.config/docker4ssh.conf",
+		"/etc/docker4ssh/docker4ssh.conf",
+	}
+
+	for _, file := range configFiles {
+		if _, err := os.Stat(file); !os.IsNotExist(err) {
+			return LoadConfig(file, includeEnv)
+		}
+	}
+
+	return nil, fmt.Errorf("no speicfied config file (%s) could be found", strings.Join(configFiles, ", "))
+}
+
+func LoadConfig(file string, includeEnv bool) (*Config, error) {
+	config := &Config{}
+
+	if _, err := toml.DecodeFile(file, config); err != nil {
+		return nil, err
+	}
+
+	// make paths absolute
+	dir := filepath.Dir(file)
+	config.Profile.Dir = absoluteFile(dir, config.Profile.Dir)
+	config.Api.Configure.Binary = absoluteFile(dir, config.Api.Configure.Binary)
+	config.Api.Configure.Man = absoluteFile(dir, config.Api.Configure.Man)
+	config.SSH.Keyfile = absoluteFile(dir, config.SSH.Keyfile)
+	config.Database.Sqlite3File = absoluteFile(dir, config.Database.Sqlite3File)
+	config.Logging.OutputFile = absoluteFile(dir, config.Logging.OutputFile)
+	config.Logging.ErrorFile = absoluteFile(dir, config.Logging.ErrorFile)
+
+	if includeEnv {
+		if err := updateFromEnv(config); err != nil {
+			return nil, err
+		}
+	}
+
+	return config, nil
+}
+
+func absoluteFile(path, file string) string {
+	if filepath.IsAbs(file) {
+		return file
+	}
+	return filepath.Join(path, file)
+}
+
+// updateFromEnv looks up if specific environment variable are given which can
+// also be used to configure the program.
+// Every key in the config file can also be specified via environment variables.
+// The env variable syntax is SECTION_KEY -> e.g. DEFAULT_PASSWORD or API_PORT
+func updateFromEnv(config *Config) error {
+	re := reflect.ValueOf(config).Elem()
+	rt := re.Type()
+
+	for i := 0; i < re.NumField(); i++ {
+		rf := re.Field(i)
+		ree := rt.Field(i)
+
+		if err := envParseField(strings.ToUpper(ree.Tag.Get("toml")), rf); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func envParseField(prefix string, value reflect.Value) error {
+	for j := 0; j < value.NumField(); j++ {
+		rtt := value.Type().Field(j)
+		rff := value.Field(j)
+
+		if rff.Kind() == reflect.Struct {
+			if err := envParseField(fmt.Sprintf("%s_%s", prefix, strings.ToUpper(rtt.Tag.Get("toml"))), rff); err != nil {
+				return err
+			}
+			continue
+		}
+
+		envName := fmt.Sprintf("%s_%s", prefix, strings.ToUpper(rtt.Tag.Get("toml")))
+		val, ok := os.LookupEnv(envName)
+		if !ok {
+			continue
+		}
+		var expected string
+		switch rff.Kind() {
+		case reflect.String:
+			rff.SetString(val)
+			continue
+		case reflect.Bool:
+			b, err := strconv.ParseBool(val)
+			if err == nil {
+				rff.SetBool(b)
+				continue
+			}
+			expected = "true / false (boolean)"
+		case reflect.Uint16:
+			ui, err := strconv.ParseUint(val, 10, 16)
+			if err == nil {
+				rff.SetUint(ui)
+				continue
+			}
+			expected = "number (uint16)"
+		default:
+			return fmt.Errorf("parsed not implemented config type '%s'", rff.Kind())
+		}
+		return fmt.Errorf("failed to parse environment variable '%s': cannot parse value '%s' as %s", envName, val, expected)
+	}
+	return nil
+}
+
+func GetConfig() *Config {
+	return globConfig
+}
+
+func SetConfig(config *Config) {
+	globConfig = config
+}