Move config into separate package

config/config.go

@@ -0,0 +1,151 @@
+package config
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+
+	"github.com/9seconds/mtg/v2/mtglib"
+	"github.com/pelletier/go-toml"
+)
+
+type Config struct {
+	Debug     bool          `json:"debug"`
+	Secret    mtglib.Secret `json:"secret"`
+	BindTo    TypeHostPort  `json:"bind-to"`
+	TCPBuffer TypeBytes     `json:"tcp-buffer"`
+	PreferIP  TypePreferIP  `json:"prefer-ip"`
+	CloakPort TypePort      `json:"cloak-port"`
+	Probes    struct {
+		Time struct {
+			Enabled       bool         `json:"enabled"`
+			AllowSkewness TypeDuration `json:"allow-skewness"`
+		} `json:"time"`
+		AntiReplay struct {
+			Enabled   bool      `json:"enabled"`
+			MaxSize   TypeBytes `json:"max-size"`
+			ErrorRate TypeFloat `json:"error-rate"`
+		} `json:"anti-replay"`
+	} `json:"probes"`
+	Network struct {
+		PublicIP struct {
+			IPv4 TypeIP `json:"ipv4"`
+			IPv6 TypeIP `json:"ipv6"`
+		} `json:"public-ip"`
+		Timeout struct {
+			TCP  TypeDuration `json:"tcp"`
+			Idle TypeDuration `json:"idle"`
+		} `json:"timeout"`
+		DOHIP   TypeIP    `json:"doh-ip"`
+		Proxies []TypeURL `json:"proxies"`
+	} `json:"network"`
+	Stats struct {
+		StatsD struct {
+			Enabled      bool             `json:"enabled"`
+			Address      TypeHostPort     `json:"address"`
+			MetricPrefix TypeMetricPrefix `json:"metric-prefix"`
+		} `json:"statsd"`
+		Prometheus struct {
+			Enabled      bool             `json:"enabled"`
+			BindTo       TypeHostPort     `json:"bind-to"`
+			HTTPPath     TypeHTTPPath     `json:"http-path"`
+			MetricPrefix TypeMetricPrefix `json:"metric-prefix"`
+		} `json:"prometheus"`
+	} `json:"stats"`
+}
+
+func (c *Config) Validate() error {
+	if len(c.Secret.Key) == 0 || c.Secret.Host == "" {
+		return fmt.Errorf("incorrect secret %s", c.Secret.String())
+	}
+
+	return nil
+}
+
+func (c *Config) String() string {
+	buf := &bytes.Buffer{}
+	encoder := json.NewEncoder(buf)
+
+	encoder.SetEscapeHTML(false)
+
+	if err := encoder.Encode(c); err != nil {
+		panic(err)
+	}
+
+	return buf.String()
+}
+
+type configRaw struct {
+	Debug     bool   `toml:"debug" json:"debug"`
+	Secret    string `toml:"secret" json:"secret"`
+	BindTo    string `toml:"bind-to" json:"bind-to"`
+	TCPBuffer string `toml:"tcp-buffer" json:"tcp-buffer"`
+	PreferIP  string `toml:"prefer-ip" json:"prefer-ip"`
+	CloakPort uint   `toml:"cloak-port" json:"cloak-port"`
+	Probes    struct {
+		Time struct {
+			Enabled       bool   `toml:"enabled" json:"enabled"`
+			AllowSkewness string `toml:"allow-skewness" json:"allow-skewness"`
+		} `toml:"time" json:"time"`
+		AntiReplay struct {
+			Enabled   bool    `toml:"enabled" json:"enabled"`
+			MaxSize   string  `toml:"max-size" json:"max-size"`
+			ErrorRate float64 `toml:"error-rate" json:"error-rate"`
+		} `toml:"anti-replay" json:"anti-replay"`
+	} `toml:"probes" json:"probes"`
+	Network struct {
+		PublicIP struct {
+			IPv4 string `toml:"ipv4" json:"ipv4"`
+			IPv6 string `toml:"ipv6" json:"ipv6"`
+		} `toml:"public-ip" json:"public-ip"`
+		Timeout struct {
+			TCP  string `toml:"tcp" json:"tcp"`
+			Idle string `toml:"idle" json:"idle"`
+		} `toml:"timeout" json:"timeout"`
+		DOHIP   string   `toml:"doh-ip" json:"doh-ip"`
+		Proxies []string `toml:"proxies" json:"proxies"`
+	} `toml:"network" json:"network"`
+	Stats struct {
+		StatsD struct {
+			Enabled      bool   `toml:"enabled" json:"enabled"`
+			Address      string `toml:"address" json:"address"`
+			MetricPrefix string `toml:"metric-prefix" json:"metric-prefix"`
+		} `toml:"statsd" json:"statsd"`
+		Prometheus struct {
+			Enabled      bool   `toml:"enabled" json:"enabled"`
+			BindTo       string `toml:"bind-to" json:"bind-to"`
+			HTTPPath     string `toml:"http-path" json:"http-path"`
+			MetricPrefix string `toml:"metric-prefix" json:"metric-prefix"`
+		} `toml:"prometheus" json:"prometheus"`
+	} `toml:"stats" json:"stats"`
+}
+
+func Parse(rawData []byte) (*Config, error) {
+	rawConf := &configRaw{}
+
+	if err := toml.Unmarshal(rawData, rawConf); err != nil {
+		return nil, fmt.Errorf("cannot parse toml config: %w", err)
+	}
+
+	jsonBuf := &bytes.Buffer{}
+	jsonEncoder := json.NewEncoder(jsonBuf)
+
+	jsonEncoder.SetEscapeHTML(false)
+	jsonEncoder.SetIndent("", "")
+
+	if err := jsonEncoder.Encode(rawConf); err != nil {
+		return nil, fmt.Errorf("cannot dump into interim format: %w", err)
+	}
+
+	conf := &Config{}
+
+	if err := json.NewDecoder(jsonBuf).Decode(conf); err != nil {
+		return nil, fmt.Errorf("cannot parse final config: %w", err)
+	}
+
+	if err := conf.Validate(); err != nil {
+		return nil, fmt.Errorf("cannot validate config: %w", err)
+	}
+
+	return conf, nil
+}

config/type_bytes.go

@@ -0,0 +1,47 @@
+package config
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/alecthomas/units"
+)
+
+type TypeBytes struct {
+	value uint
+}
+
+func (c *TypeBytes) UnmarshalText(data []byte) error {
+	if len(data) == 0 {
+		return nil
+	}
+
+	value, err := units.ParseStrictBytes(strings.ToUpper(string(data)))
+	if err != nil {
+		return fmt.Errorf("incorrect bytes value: %w", err)
+	}
+
+	if value < 0 {
+		return fmt.Errorf("%d should be positive number", value)
+	}
+
+	c.value = uint(value)
+
+	return nil
+}
+
+func (c TypeBytes) MarshalText() ([]byte, error) { // nolint: unparam
+	return []byte(c.String()), nil
+}
+
+func (c TypeBytes) String() string {
+	return units.ToString(int64(c.value), 1024, "ib", "b")
+}
+
+func (c TypeBytes) Value(defaultValue uint) uint {
+	if c.value == 0 {
+		return defaultValue
+	}
+
+	return c.value
+}

config/type_duration.go

@@ -0,0 +1,46 @@
+package config
+
+import (
+	"fmt"
+	"strings"
+	"time"
+)
+
+type TypeDuration struct {
+	value time.Duration
+}
+
+func (c *TypeDuration) UnmarshalText(data []byte) error {
+	if len(data) == 0 {
+		return nil
+	}
+
+	dur, err := time.ParseDuration(strings.ToLower(string(data)))
+	if err != nil {
+		return fmt.Errorf("incorrect duration: %w", err)
+	}
+
+	if dur < 0 {
+		return fmt.Errorf("%s should be positive duration", dur)
+	}
+
+	c.value = dur
+
+	return nil
+}
+
+func (c TypeDuration) MarshalText() ([]byte, error) { // nolint: unparam
+	return []byte(c.value.String()), nil
+}
+
+func (c TypeDuration) String() string {
+	return c.value.String()
+}
+
+func (c TypeDuration) Value(defaultValue time.Duration) time.Duration {
+	if c.value == 0 {
+		return defaultValue
+	}
+
+	return c.value
+}

config/type_float.go

@@ -0,0 +1,41 @@
+package config
+
+import (
+	"fmt"
+	"strconv"
+)
+
+type TypeFloat struct {
+	value float64
+}
+
+func (c *TypeFloat) UnmarshalJSON(data []byte) error {
+	value, err := strconv.ParseFloat(string(data), 64)
+	if err != nil {
+		return fmt.Errorf("incorrect float value: %w", err)
+	}
+
+	if value < 0 {
+		return fmt.Errorf("%f should be positive", value)
+	}
+
+	c.value = value
+
+	return nil
+}
+
+func (c *TypeFloat) MarshalText() ([]byte, error) { // nolint: unparam
+	return []byte(c.String()), nil
+}
+
+func (c TypeFloat) String() string {
+	return strconv.FormatFloat(c.value, 'f', -1, 64)
+}
+
+func (c TypeFloat) Value(defaultValue float64) float64 {
+	if c.value < 0.00001 {
+		return defaultValue
+	}
+
+	return c.value
+}

config/type_hostport.go

@@ -0,0 +1,56 @@
+package config
+
+import (
+	"fmt"
+	"net"
+	"strconv"
+)
+
+type TypeHostPort struct {
+	host TypeIP
+	port TypePort
+}
+
+func (c *TypeHostPort) UnmarshalText(data []byte) error {
+	if len(data) == 0 {
+		return nil
+	}
+
+	host, port, err := net.SplitHostPort(string(data))
+	if err != nil {
+		return fmt.Errorf("incorrect host:port syntax: %w", err)
+	}
+
+	if err := c.port.UnmarshalJSON([]byte(port)); err != nil {
+		return fmt.Errorf("incorrect port in host:port: %w", err)
+	}
+
+	if err := c.host.UnmarshalText([]byte(host)); err != nil {
+		return fmt.Errorf("incorrect host: %w", err)
+	}
+
+	return nil
+}
+
+func (c TypeHostPort) MarshalText() ([]byte, error) { // nolint: unparam
+	return []byte(c.String()), nil
+}
+
+func (c TypeHostPort) String() string {
+	return c.Value(net.IP{}, 0)
+}
+
+func (c TypeHostPort) HostValue(defaultValue net.IP) net.IP {
+    return c.host.Value(defaultValue)
+}
+
+func (c TypeHostPort) PortValue(defaultValue uint) uint {
+    return c.port.Value(defaultValue)
+}
+
+func (c TypeHostPort) Value(defaultHostValue net.IP, defaultPortValue uint) string {
+	host := c.HostValue(defaultHostValue)
+	port := c.PortValue(defaultPortValue)
+
+	return net.JoinHostPort(host.String(), strconv.Itoa(int(port)))
+}

config/type_http_path.go

@@ -0,0 +1,31 @@
+package config
+
+import "strings"
+
+type TypeHTTPPath struct {
+	value string
+}
+
+func (c *TypeHTTPPath) UnmarshalText(data []byte) error { // nolint: unparam
+	if len(data) > 0 {
+		c.value = "/" + strings.Trim(string(data), "/")
+	}
+
+	return nil
+}
+
+func (c TypeHTTPPath) MarshalText() ([]byte, error) { // nolint: unparam
+	return []byte(c.String()), nil
+}
+
+func (c TypeHTTPPath) String() string {
+	return c.value
+}
+
+func (c TypeHTTPPath) Value(defaultValue string) string {
+	if c.value == "" {
+		return defaultValue
+	}
+
+	return c.value
+}

config/type_ip.go

@@ -0,0 +1,45 @@
+package config
+
+import (
+	"fmt"
+	"net"
+)
+
+type TypeIP struct {
+	value net.IP
+}
+
+func (c *TypeIP) UnmarshalText(data []byte) error {
+	if len(data) == 0 {
+		return nil
+	}
+
+	ip := net.ParseIP(string(data))
+	if ip == nil {
+		return fmt.Errorf("incorrect ip address: %s", string(data))
+	}
+
+	c.value = ip
+
+	return nil
+}
+
+func (c *TypeIP) MarshalText() ([]byte, error) { // nolint: unparam
+	return []byte(c.String()), nil
+}
+
+func (c TypeIP) String() string {
+	if c.value == nil {
+		return ""
+	}
+
+	return c.value.String()
+}
+
+func (c TypeIP) Value(defaultValue net.IP) net.IP {
+	if c.value == nil {
+		return defaultValue
+	}
+
+	return c.value
+}

config/type_metric_prefix.go

@@ -0,0 +1,42 @@
+package config
+
+import (
+	"fmt"
+	"regexp"
+)
+
+type TypeMetricPrefix struct {
+	value string
+}
+
+func (c *TypeMetricPrefix) UnmarshalText(data []byte) error {
+	if len(data) == 0 {
+		return nil
+	}
+
+	prefix := string(data)
+
+	if ok, err := regexp.MatchString("^[a-z0-9]+$", prefix); !ok || err != nil {
+		return fmt.Errorf("incorrect metric prefix: %s", prefix)
+	}
+
+	c.value = prefix
+
+	return nil
+}
+
+func (c TypeMetricPrefix) MarshalText() ([]byte, error) { // nolint: unparam
+	return []byte(c.String()), nil
+}
+
+func (c TypeMetricPrefix) String() string {
+	return c.value
+}
+
+func (c TypeMetricPrefix) Value(defaultValue string) string {
+	if c.value == "" {
+		return defaultValue
+	}
+
+	return c.value
+}

config/type_port.go

@@ -0,0 +1,45 @@
+package config
+
+import (
+	"fmt"
+	"strconv"
+)
+
+type TypePort struct {
+	value uint
+}
+
+func (c *TypePort) UnmarshalJSON(data []byte) error {
+	if len(data) == 0 {
+		return nil
+	}
+
+	intValue, err := strconv.ParseUint(string(data), 10, 16)
+	if err != nil {
+		return fmt.Errorf("port number is not a number: %w", err)
+	}
+
+	if intValue == 0 || intValue > 65536 {
+		return fmt.Errorf("port number should be 0 < portNo < 65536: %d", intValue)
+	}
+
+	c.value = uint(intValue)
+
+	return nil
+}
+
+func (c *TypePort) MarshalJSON() ([]byte, error) { // nolint: unparam
+    return []byte(c.String()), nil
+}
+
+func (c TypePort) String() string {
+	return strconv.Itoa(int(c.value))
+}
+
+func (c TypePort) Value(defaultValue uint) uint {
+	if c.value == 0 {
+		return defaultValue
+	}
+
+	return c.value
+}

config/type_prefer_ip.go

@@ -0,0 +1,43 @@
+package config
+
+import (
+	"fmt"
+	"strings"
+)
+
+type TypePreferIP struct {
+	value string
+}
+
+func (c *TypePreferIP) UnmarshalText(data []byte) error {
+	if len(data) == 0 {
+		return nil
+	}
+
+	text := strings.ToLower(string(data))
+
+	switch text {
+	case "prefer-ipv4", "prefer-ipv6", "only-ipv4", "only-ipv6":
+		c.value = text
+	default:
+		return fmt.Errorf("incorrect prefer-ip value: %s", string(data))
+	}
+
+	return nil
+}
+
+func (c TypePreferIP) MarshalText() ([]byte, error) { // nolint: unparam
+	return []byte(c.value), nil
+}
+
+func (c *TypePreferIP) String() string {
+	return c.value
+}
+
+func (c *TypePreferIP) Value(defaultValue string) string {
+	if c.value == "" {
+		return defaultValue
+	}
+
+	return c.value
+}

config/type_url.go

@@ -0,0 +1,45 @@
+package config
+
+import (
+	"fmt"
+	"net/url"
+)
+
+type TypeURL struct {
+	value *url.URL
+}
+
+func (c *TypeURL) UnmarshalText(data []byte) error {
+	if len(data) == 0 {
+		return nil
+	}
+
+	value, err := url.Parse(string(data))
+	if err != nil {
+		return fmt.Errorf("incorrect URL: %w", err)
+	}
+
+	c.value = value
+
+	return nil
+}
+
+func (c *TypeURL) MarshalText() ([]byte, error) { // nolint: unparam
+	return []byte(c.String()), nil
+}
+
+func (c TypeURL) String() string {
+	if c.value == nil {
+		return ""
+	}
+
+	return c.value.String()
+}
+
+func (c TypeURL) Value(defaultValue *url.URL) *url.URL {
+	if c.value == nil {
+		return defaultValue
+	}
+
+	return c.value
+}