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-rw-r--r--src/lib.go744
1 files changed, 423 insertions, 321 deletions
diff --git a/src/lib.go b/src/lib.go
index 14f4f33..391e629 100644
--- a/src/lib.go
+++ b/src/lib.go
@@ -14,105 +14,18 @@ import (
"math/big"
"math/bits"
"os"
+ "reflect"
"runtime/debug"
+ "strings"
"sync"
"syscall"
+ "testing"
"time"
)
-// FIXME: finish rewriting
-//
-// lastV7time is the last time we returned stored as:
-//
-// 52 bits of time in milliseconds since epoch
-// 12 bits of (fractional nanoseconds) >> 8
-var lastV7Time int64
-var timeMu sync.Mutex
-// getV7Time returns the time in milliseconds and nanoseconds / 256.
-// The returned (milli << (12 + seq)) is guaranteed to be greater than
-// (milli << (12 + seq)) returned by any previous call to getV7Time.
-// `seq` Sequence number is between 0 and 3906 (nanoPerMilli >> 8)
-func getV7Time(nano int64) (int64, int64) {
- const nanoPerMilli = 1000 * 1000
-
- milli := nano / nanoPerMilli
- seq := (nano - (milli * nanoPerMilli)) >> 8
- now := milli << (12 + seq)
-
- timeMu.Lock()
- defer timeMu.Unlock()
- if now <= lastV7Time {
- now = lastV7Time + 1
- milli = now >> 12
- seq = now & 0xfff
- }
- lastV7Time = now
- return milli, seq
-}
-
-const lengthUUID = 16
-
-type UUID struct {
- bytes [lengthUUID]byte
-}
-
-func NewUUID() UUID {
- var buf [lengthUUID]byte
- _, err := io.ReadFull(rand.Reader, buf[7:])
- if err != nil {
- panic(err)
- }
-
- buf[6] = (buf[6] & 0x0f) | 0x40 // Version 4
- buf[8] = (buf[8] & 0x3f) | 0x80 // Variant is 10
-
- t, s := getV7Time(time.Now().UnixNano())
-
- buf[0] = byte(t >> 40)
- buf[1] = byte(t >> 32)
- buf[2] = byte(t >> 24)
- buf[3] = byte(t >> 16)
- buf[4] = byte(t >> 8)
- buf[5] = byte(t >> 0)
-
- buf[6] = 0x70 | (0x0f & byte(s >> 8))
- buf[7] = byte(s)
- return UUID { bytes: buf }
-}
-
-func (uuid UUID) ToString() string {
- const dashCount = 4
- const encodedLength = (lengthUUID * 2) + dashCount
- dst := [encodedLength]byte {
- 0, 0, 0, 0,
- 0, 0, 0, 0,
- '-',
- 0, 0, 0, 0,
- '-',
- 0, 0, 0, 0,
- '-',
- 0, 0, 0, 0,
- '-',
- 0, 0, 0, 0,
- 0, 0, 0, 0,
- 0, 0, 0, 0,
- }
-
- hex.Encode(dst[ 0:8], uuid.bytes[0:4])
- hex.Encode(dst[ 9:13], uuid.bytes[4:6])
- hex.Encode(dst[14:18], uuid.bytes[6:8])
- hex.Encode(dst[19:23], uuid.bytes[8:10])
- hex.Encode(dst[24:36], uuid.bytes[10:])
-
- return string(dst[:])
-}
-
-
-
type LogLevel int8
-
const (
LevelNone LogLevel = 0
LevelError LogLevel = 1
@@ -121,100 +34,9 @@ const (
LevelDebug LogLevel = 4
)
-var Level LogLevel = LevelInfo
-
-var EmitMetric bool = true
-
-
-func Debug(message string, type_ string, args ...any) {
- if (Level < LevelDebug) {
- return
- }
-
- slog.Debug(
- message,
- append(
- []any {
- "id", NewUUID().ToString(),
- "kind", "log",
- "type", type_,
- },
- args...,
- )...,
- )
-}
-
-func Info(message string, type_ string, args ...any) {
- if (Level < LevelInfo) {
- return
- }
-
- slog.Info(
- message,
- append(
- []any {
- "id", NewUUID().ToString(),
- "kind", "log",
- "type", type_,
- },
- args...,
- )...,
- )
-}
-
-func Warning(message string, type_ string, args ...any) {
- if (Level < LevelWarning) {
- return
- }
-
- slog.Warn(
- message,
- append(
- []any {
- "id", NewUUID().ToString(),
- "kind", "log",
- "type", type_,
- },
- args...,
- )...,
- )
-}
-
-func Error(message string, type_ string, args ...any) {
- if (Level < LevelError) {
- return
- }
-
- slog.Error(
- message,
- append(
- []any {
- "id", NewUUID().ToString(),
- "kind", "log",
- "type", type_,
- },
- args...,
- )...,
- )
-}
-
-func Metric(type_ string, label string, args ...any) {
- if (!EmitMetric) {
- return
- }
-
- slog.Info(
- "_",
- append(
- []any {
- "id", NewUUID().ToString(),
- "kind", "metric",
- "type", type_,
- "label", label,
- },
- args...,
- )...,
- )
+const lengthUUID = 16
+type UUID struct {
+ bytes [lengthUUID]byte
}
type Gauge struct {
@@ -222,119 +44,44 @@ type Gauge struct {
Dec func(...any)
}
-var zero = big.NewInt(0)
-var one = big.NewInt(1)
-func MakeGauge(label string, staticArgs ...any) Gauge {
- count := big.NewInt(0)
- emitGauge := func(dynamicArgs ...any) {
- if count.Cmp(zero) == -1 {
- Error(
- "Gauge went negative",
- "process-metric",
- append(
- []any { "value", count },
- append(
- staticArgs,
- dynamicArgs...,
- )...,
- )...,
- )
- return // avoid wrong metrics being emitted
- }
- Metric(
- "gauge", label,
- // TODO: we'll have slices.Concat on Go 1.22
- append(
- []any { "value", count },
- append(
- staticArgs,
- dynamicArgs...,
- )...,
- )...,
- )
- }
- return Gauge {
- Inc: func(dynamicArgs ...any) {
- count.Add(count, one)
- emitGauge(dynamicArgs...)
- },
- Dec: func(dynamicArgs ...any) {
- count.Sub(count, one)
- emitGauge(dynamicArgs...)
- },
- }
-}
-
-func MakeCounter(label string) func(...any) {
- return func(args ...any) {
- Metric(
- "counter", label,
- append([]any { "value", 1 }, args...)...,
- )
- }
-}
-
-func SetLoggerOutput(w io.Writer) {
- slog.SetDefault(slog.New(slog.NewJSONHandler(w, &slog.HandlerOptions {
- AddSource: true,
- })).With(
- slog.Group(
- "info",
- "pid", os.Getpid(),
- "ppid", os.Getppid(),
- "puuid", NewUUID().ToString(),
- ),
- ))
-}
-
-func SetTraceback() {
- if os.Getenv("GOTRACEBACK") == "" {
- debug.SetTraceback("crash")
- }
-}
-func Init() {
- SetLoggerOutput(os.Stdout)
- SetTraceback()
-}
-func Fatal(err error) {
- Error(
- "Fatal error", "fatal-error",
- "error", err,
- "stack", string(debug.Stack()),
- )
- syscall.Kill(os.Getpid(), syscall.SIGABRT)
- os.Exit(3)
-}
+const MaxInt = int((^uint(0)) >> 1)
-func FatalIf(err error) {
- if err != nil {
- Fatal(err)
- }
-}
-func Main() {
- fmt.Println(NewUUID().ToString())
-}
+// Private variables
+// lastV7time is the last time we returned stored as:
+//
+// 52 bits of time in milliseconds since epoch
+// 12 bits of (fractional nanoseconds) >> 8
+var lastV7Time int64
+var timeMu sync.Mutex
-/*
-Package pbkdf2 implements the key derivation function PBKDF2 as defined in RFC
-2898 / PKCS #5 v2.0.
+// Global variables
+var (
+ Level LogLevel = LevelInfo
+ EmitMetric bool = true
+ Hostname string
+)
-A key derivation function is useful when encrypting data based on a password
-or any other not-fully-random data. It uses a pseudorandom function to derive
-a secure encryption key based on the password.
-While v2.0 of the standard defines only one pseudorandom function to use,
-HMAC-SHA1, the drafted v2.1 specification allows use of all five FIPS Approved
-Hash Functions SHA-1, SHA-224, SHA-256, SHA-384 and SHA-512 for HMAC. To
-choose, you can pass the `New` functions from the different SHA packages to
-pbkdf2.Key.
-*/
+// Package pbkdf2 implements the key derivation function PBKDF2 as defined in
+// RFC 2898 / PKCS #5 v2.0.
+//
+// A key derivation function is useful when encrypting data based on a password
+// or any other not-fully-random data. It uses a pseudorandom function to derive
+// a secure encryption key based on the password.
+//
+// While v2.0 of the standard defines only one pseudorandom function to use,
+// HMAC-SHA1, the drafted v2.1 specification allows use of all five FIPS
+// Approved Hash Functions SHA-1, SHA-224, SHA-256, SHA-384 and SHA-512 for
+// HMAC. To choose, you can pass the `New` functions from the different SHA
+// packages to pbkdf2.Key.
+//
+//
// Key derives a key from the password, salt and iteration count, returning a
// []byte of length keylen that can be used as cryptographic key. The key is
// derived based on the method described as PBKDF2 with the HMAC variant using
@@ -351,7 +98,13 @@ pbkdf2.Key.
//
// Using a higher iteration count will increase the cost of an exhaustive
// search but will also make derivation proportionally slower.
-func PBKDF2Key(password, salt []byte, iter, keyLen int, h func() hash.Hash) []byte {
+func PBKDF2Key(
+ password []byte,
+ salt []byte,
+ iter int,
+ keyLen int,
+ h func() hash.Hash,
+) []byte {
prf := hmac.New(h, password)
hashLen := prf.Size()
numBlocks := (keyLen + hashLen - 1) / hashLen
@@ -371,10 +124,10 @@ func PBKDF2Key(password, salt []byte, iter, keyLen int, h func() hash.Hash) []by
buf[3] = byte(block)
prf.Write(buf[:4])
dk = prf.Sum(dk)
- T := dk[len(dk)-hashLen:]
+ T := dk[len(dk) - hashLen:]
copy(U, T)
- // U_n = PRF(password, U_(n-1))
+ // U_n = PRF(password, U_(n - 1))
for n := 2; n <= iter; n++ {
prf.Reset()
prf.Write(U)
@@ -388,19 +141,13 @@ func PBKDF2Key(password, salt []byte, iter, keyLen int, h func() hash.Hash) []by
return dk[:keyLen]
}
-// Package scrypt implements the scrypt key derivation function as defined in
-// Colin Percival's paper "Stronger Key Derivation via Sequential Memory-Hard
-// Functions" (https://www.tarsnap.com/scrypt/scrypt.pdf).
-
-const maxInt = int(^uint(0) >> 1)
-
// blockCopy copies n numbers from src into dst.
-func blockCopy(dst, src []uint32, n int) {
+func blockCopy(dst []uint32, src []uint32, n int) {
copy(dst, src[:n])
}
// blockXOR XORs numbers from dst with n numbers from src.
-func blockXOR(dst, src []uint32, n int) {
+func blockXOR(dst []uint32, src []uint32, n int) {
for i, v := range src[:n] {
dst[i] ^= v
}
@@ -408,7 +155,7 @@ func blockXOR(dst, src []uint32, n int) {
// salsaXOR applies Salsa20/8 to the XOR of 16 numbers from tmp and in,
// and puts the result into both tmp and out.
-func salsaXOR(tmp *[16]uint32, in, out []uint32) {
+func salsaXOR(tmp *[16]uint32, in []uint32, out []uint32) {
w0 := tmp[0] ^ in[0]
w1 := tmp[1] ^ in[1]
w2 := tmp[2] ^ in[2]
@@ -520,20 +267,20 @@ func salsaXOR(tmp *[16]uint32, in, out []uint32) {
out[15], tmp[15] = x15, x15
}
-func blockMix(tmp *[16]uint32, in, out []uint32, r int) {
- blockCopy(tmp[:], in[(2*r-1)*16:], 16)
- for i := 0; i < 2*r; i += 2 {
- salsaXOR(tmp, in[i*16:], out[i*8:])
- salsaXOR(tmp, in[i*16+16:], out[i*8+r*16:])
+func blockMix(tmp *[16]uint32, in []uint32, out []uint32, r int) {
+ blockCopy(tmp[:], in[(2 * r - 1) * 16:], 16)
+ for i := 0; i < 2 * r; i += 2 {
+ salsaXOR(tmp, in[i * 16:], out[i * 8:])
+ salsaXOR(tmp, in[i * 16 + 16:], out[i * 8 + r * 16:])
}
}
func integer(b []uint32, r int) uint64 {
- j := (2*r - 1) * 16
- return uint64(b[j]) | uint64(b[j+1])<<32
+ j := (2 * r - 1) * 16
+ return uint64(b[j]) | (uint64(b[j + 1]) << 32)
}
-func smix(b []byte, r, N int, v, xy []uint32) {
+func smix(b []byte, r int, N int, v []uint32, xy []uint32) {
var tmp [16]uint32
R := 32 * r
x := xy
@@ -545,19 +292,19 @@ func smix(b []byte, r, N int, v, xy []uint32) {
j += 4
}
for i := 0; i < N; i += 2 {
- blockCopy(v[i*R:], x, R)
+ blockCopy(v[i * R:], x, R)
blockMix(&tmp, x, y, r)
- blockCopy(v[(i+1)*R:], y, R)
+ blockCopy(v[(i + 1) * R:], y, R)
blockMix(&tmp, y, x, r)
}
for i := 0; i < N; i += 2 {
- j := int(integer(x, r) & uint64(N-1))
- blockXOR(x, v[j*R:], R)
+ j := int(integer(x, r) & uint64(N - 1))
+ blockXOR(x, v[j * R:], R)
blockMix(&tmp, x, y, r)
- j = int(integer(y, r) & uint64(N-1))
- blockXOR(y, v[j*R:], R)
+ j = int(integer(y, r) & uint64(N - 1))
+ blockXOR(y, v[j * R:], R)
blockMix(&tmp, y, x, r)
}
j = 0
@@ -567,10 +314,15 @@ func smix(b []byte, r, N int, v, xy []uint32) {
}
}
+// Package scrypt implements the scrypt key derivation function as defined in
+// Colin Percival's paper "Stronger Key Derivation via Sequential Memory-Hard
+// Functions" (https://www.tarsnap.com/scrypt/scrypt.pdf).
+//
+//
// Key derives a key from the password, salt, and cost parameters, returning
// a byte slice of length keyLen that can be used as cryptographic key.
//
-// N is a CPU/memory cost parameter, which must be a power of two greater than 1.
+// N is a CPU/memory cost parameter, which must be a power of 2 greater than 1.
// r and p must satisfy r * p < 2³⁰. If the parameters do not satisfy the
// limits, the function returns a nil byte slice and an error.
//
@@ -583,21 +335,371 @@ func smix(b []byte, r, N int, v, xy []uint32) {
// and p=1. The parameters N, r, and p should be increased as memory latency and
// CPU parallelism increases; consider setting N to the highest power of 2 you
// can derive within 100 milliseconds. Remember to get a good random salt.
-func Scrypt(password, salt []byte, N, r, p, keyLen int) ([]byte, error) {
- if N <= 1 || N&(N-1) != 0 {
+func Scrypt(
+ password []byte,
+ salt []byte,
+ N int,
+ r int,
+ p int,
+ keyLen int,
+) ([]byte, error) {
+ if N <= 1 || N & (N - 1) != 0 {
return nil, errors.New("scrypt: N must be > 1 and a power of 2")
}
- if uint64(r)*uint64(p) >= 1<<30 || r > maxInt/128/p || r > maxInt/256 || N > maxInt/128/r {
+ if ((uint64(r) * uint64(p)) >= (1 << 30)) ||
+ r > MaxInt / 128 / p ||
+ r > MaxInt / 256 ||
+ N > MaxInt / 128 / r {
return nil, errors.New("scrypt: parameters are too large")
}
- xy := make([]uint32, 64*r)
- v := make([]uint32, 32*N*r)
- b := PBKDF2Key(password, salt, 1, p*128*r, sha256.New)
+ xy := make([]uint32, 64 * r)
+ v := make([]uint32, 32 * N * r)
+ b := PBKDF2Key(password, salt, 1, p * 128 * r, sha256.New)
for i := 0; i < p; i++ {
- smix(b[i*128*r:], r, N, v, xy)
+ smix(b[i * 128 * r:], r, N, v, xy)
}
return PBKDF2Key(password, b, 1, keyLen, sha256.New), nil
}
+
+// FIXME: finish rewriting
+//
+// getV7Time returns the time in milliseconds and nanoseconds / 256.
+// The returned (milli << (12 + seq)) is guaranteed to be greater than
+// (milli << (12 + seq)) returned by any previous call to getV7Time.
+// `seq` Sequence number is between 0 and 3906 (nanoPerMilli >> 8)
+func getV7Time(nano int64) (int64, int64) {
+ const nanoPerMilli = 1000 * 1000
+
+ milli := nano / nanoPerMilli
+ seq := (nano - (milli * nanoPerMilli)) >> 8
+ now := milli << (12 + seq)
+
+ timeMu.Lock()
+ defer timeMu.Unlock()
+ if now <= lastV7Time {
+ now = lastV7Time + 1
+ milli = now >> 12
+ seq = now & 0xfff
+ }
+ lastV7Time = now
+ return milli, seq
+}
+
+func NewUUID() UUID {
+ var buf [lengthUUID]byte
+ _, err := io.ReadFull(rand.Reader, buf[7:])
+ if err != nil {
+ panic(err)
+ }
+
+ buf[6] = (buf[6] & 0x0f) | 0x40 // Version 4
+ buf[8] = (buf[8] & 0x3f) | 0x80 // Variant is 10
+
+ t, s := getV7Time(time.Now().UnixNano())
+
+ buf[0] = byte(t >> 40)
+ buf[1] = byte(t >> 32)
+ buf[2] = byte(t >> 24)
+ buf[3] = byte(t >> 16)
+ buf[4] = byte(t >> 8)
+ buf[5] = byte(t >> 0)
+
+ buf[6] = 0x70 | (0x0f & byte(s >> 8))
+ buf[7] = byte(s)
+ return UUID { bytes: buf }
+}
+
+func (uuid UUID) ToString() string {
+ const dashCount = 4
+ const encodedLength = (lengthUUID * 2) + dashCount
+ dst := [encodedLength]byte {
+ 0, 0, 0, 0,
+ 0, 0, 0, 0,
+ '-',
+ 0, 0, 0, 0,
+ '-',
+ 0, 0, 0, 0,
+ '-',
+ 0, 0, 0, 0,
+ '-',
+ 0, 0, 0, 0,
+ 0, 0, 0, 0,
+ 0, 0, 0, 0,
+ }
+
+ hex.Encode(dst[ 0:8], uuid.bytes[0:4])
+ hex.Encode(dst[ 9:13], uuid.bytes[4:6])
+ hex.Encode(dst[14:18], uuid.bytes[6:8])
+ hex.Encode(dst[19:23], uuid.bytes[8:10])
+ hex.Encode(dst[24:36], uuid.bytes[10:])
+
+ return string(dst[:])
+}
+
+func Debug(message string, type_ string, args ...any) {
+ if Level < LevelDebug {
+ return
+ }
+
+ slog.Debug(
+ message,
+ append(
+ []any {
+ "id", NewUUID().ToString(),
+ "kind", "log",
+ "type", type_,
+ },
+ args...,
+ )...,
+ )
+}
+
+func Info(message string, type_ string, args ...any) {
+ if Level < LevelInfo {
+ return
+ }
+
+ slog.Info(
+ message,
+ append(
+ []any {
+ "id", NewUUID().ToString(),
+ "kind", "log",
+ "type", type_,
+ },
+ args...,
+ )...,
+ )
+}
+
+func Warning(message string, type_ string, args ...any) {
+ if Level < LevelWarning {
+ return
+ }
+
+ slog.Warn(
+ message,
+ append(
+ []any {
+ "id", NewUUID().ToString(),
+ "kind", "log",
+ "type", type_,
+ },
+ args...,
+ )...,
+ )
+}
+
+func Error(message string, type_ string, args ...any) {
+ if Level < LevelError {
+ return
+ }
+
+ slog.Error(
+ message,
+ append(
+ []any {
+ "id", NewUUID().ToString(),
+ "kind", "log",
+ "type", type_,
+ },
+ args...,
+ )...,
+ )
+}
+
+func Metric(type_ string, label string, args ...any) {
+ if !EmitMetric {
+ return
+ }
+
+ slog.Info(
+ "_",
+ append(
+ []any {
+ "id", NewUUID().ToString(),
+ "kind", "metric",
+ "type", type_,
+ "label", label,
+ },
+ args...,
+ )...,
+ )
+}
+
+func MakeGauge(label string, staticArgs ...any) Gauge {
+ var zero = big.NewInt(0)
+ var one = big.NewInt(1)
+ count := big.NewInt(0)
+ emitGauge := func(dynamicArgs ...any) {
+ if count.Cmp(zero) == -1 {
+ Error(
+ "Gauge went negative",
+ "process-metric",
+ append(
+ []any { "value", count },
+ append(
+ staticArgs,
+ dynamicArgs...,
+ )...,
+ )...,
+ )
+ return // avoid wrong metrics being emitted
+ }
+ Metric(
+ "gauge", label,
+ // TODO: we'll have slices.Concat on Go 1.22
+ append(
+ []any { "value", count },
+ append(
+ staticArgs,
+ dynamicArgs...,
+ )...,
+ )...,
+ )
+ }
+ return Gauge {
+ Inc: func(dynamicArgs ...any) {
+ count.Add(count, one)
+ emitGauge(dynamicArgs...)
+ },
+ Dec: func(dynamicArgs ...any) {
+ count.Sub(count, one)
+ emitGauge(dynamicArgs...)
+ },
+ }
+}
+
+func MakeCounter(label string) func(...any) {
+ return func(args ...any) {
+ Metric(
+ "counter", label,
+ append([]any { "value", 1 }, args...)...,
+ )
+ }
+}
+
+func ErrorIf(t *testing.T, err error) {
+ if err != nil {
+ t.Errorf("Unexpected error: %#v\n", err)
+ }
+}
+
+func ErrorNil(t *testing.T, err error) {
+ if err == nil {
+ t.Errorf("Expected error, got nil\n")
+ }
+}
+
+func AssertEqual(t *testing.T, given any, expected any) {
+ if !reflect.DeepEqual(given, expected) {
+ t.Errorf("given != expected\n")
+ t.Errorf("given: %#v\n", given)
+ t.Errorf("expected: %#v\n", expected)
+ }
+}
+
+func AssertEqualI(t *testing.T, i int, given any, expected any) {
+ if !reflect.DeepEqual(given, expected) {
+ t.Errorf("given != expected (i = %d)\n", i)
+ t.Errorf("given: %#v\n", given)
+ t.Errorf("expected: %#v\n", expected)
+ }
+}
+
+func SetLoggerOutput(w io.Writer) {
+ slog.SetDefault(slog.New(slog.NewJSONHandler(w, &slog.HandlerOptions {
+ AddSource: true,
+ })).With(
+ slog.Group(
+ "info",
+ "pid", os.Getpid(),
+ "ppid", os.Getppid(),
+ "puuid", NewUUID().ToString(),
+ ),
+ ))
+}
+
+func LevelFromString(name string) (bool, LogLevel) {
+ level := strings.ToUpper(name)
+
+ if level == "NONE" {
+ return true, LevelNone
+ }
+
+ if level == "ERROR" {
+ return true, LevelError
+ }
+
+ if level == "WARNING" {
+ return true, LevelWarning
+ }
+
+ if level == "INFO" {
+ return true, LevelInfo
+ }
+
+ if level == "DEBUG" {
+ return true, LevelDebug
+ }
+
+ return false, Level
+}
+
+func SetLogLevel() {
+ ok, level := LevelFromString(os.Getenv("LOG_LEVEL"))
+
+ if ok {
+ Level = level
+ }
+}
+
+func SetMetric() {
+ if os.Getenv("NO_METRIC") != "" {
+ EmitMetric = false
+ }
+}
+
+func SetTraceback() {
+ if os.Getenv("GOTRACEBACK") == "" {
+ debug.SetTraceback("crash")
+ }
+}
+
+func Fatal(err error) {
+ Error(
+ "Fatal error", "fatal-error",
+ "error", err,
+ "stack", string(debug.Stack()),
+ )
+ syscall.Kill(os.Getpid(), syscall.SIGABRT)
+ os.Exit(3)
+}
+
+func FatalIf(err error) {
+ if err != nil {
+ Fatal(err)
+ }
+}
+
+func SetHostname() {
+ var err error
+ Hostname, err = os.Hostname()
+ FatalIf(err)
+}
+
+func Init() {
+ SetLoggerOutput(os.Stdout)
+ SetLogLevel()
+ SetMetric()
+ SetTraceback()
+ SetHostname()
+}
+
+
+func Main() {
+ fmt.Println(NewUUID().ToString())
+}