From a02aeeb90614cc574245259f51ddcdeb6eb90747 Mon Sep 17 00:00:00 2001 From: arraykeys Date: Fri, 1 Dec 2017 23:52:21 +0800 Subject: [PATCH] no message --- utils/functions.go | 9 +- utils/id/xid.go | 264 +++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 269 insertions(+), 4 deletions(-) create mode 100644 utils/id/xid.go diff --git a/utils/functions.go b/utils/functions.go index 3698184..f0bbaaa 100755 --- a/utils/functions.go +++ b/utils/functions.go @@ -12,7 +12,6 @@ import ( "io" "io/ioutil" "log" - "math/rand" "net" "net/http" "os" @@ -20,6 +19,7 @@ import ( "golang.org/x/crypto/pbkdf2" + "proxy/utils/id" "strconv" "strings" "time" @@ -301,9 +301,10 @@ func ReadUDPPacket(_reader io.Reader) (srcAddr string, packet []byte, err error) return } func Uniqueid() string { - var src = rand.NewSource(time.Now().UnixNano()) - s := fmt.Sprintf("%d", src.Int63()) - return s[len(s)-5:len(s)-1] + fmt.Sprintf("%d", uint64(time.Now().UnixNano()))[8:] + return xid.New().String() + // var src = rand.NewSource(time.Now().UnixNano()) + // s := fmt.Sprintf("%d", src.Int63()) + // return s[len(s)-5:len(s)-1] + fmt.Sprintf("%d", uint64(time.Now().UnixNano()))[8:] } func ReadData(r io.Reader) (data string, err error) { var len uint16 diff --git a/utils/id/xid.go b/utils/id/xid.go new file mode 100644 index 0000000..e76f9ef --- /dev/null +++ b/utils/id/xid.go @@ -0,0 +1,264 @@ +// Package xid is a globally unique id generator suited for web scale +// +// Xid is using Mongo Object ID algorithm to generate globally unique ids: +// https://docs.mongodb.org/manual/reference/object-id/ +// +// - 4-byte value representing the seconds since the Unix epoch, +// - 3-byte machine identifier, +// - 2-byte process id, and +// - 3-byte counter, starting with a random value. +// +// The binary representation of the id is compatible with Mongo 12 bytes Object IDs. +// The string representation is using base32 hex (w/o padding) for better space efficiency +// when stored in that form (20 bytes). The hex variant of base32 is used to retain the +// sortable property of the id. +// +// Xid doesn't use base64 because case sensitivity and the 2 non alphanum chars may be an +// issue when transported as a string between various systems. Base36 wasn't retained either +// because 1/ it's not standard 2/ the resulting size is not predictable (not bit aligned) +// and 3/ it would not remain sortable. To validate a base32 `xid`, expect a 20 chars long, +// all lowercase sequence of `a` to `v` letters and `0` to `9` numbers (`[0-9a-v]{20}`). +// +// UUID is 16 bytes (128 bits), snowflake is 8 bytes (64 bits), xid stands in between +// with 12 bytes with a more compact string representation ready for the web and no +// required configuration or central generation server. +// +// Features: +// +// - Size: 12 bytes (96 bits), smaller than UUID, larger than snowflake +// - Base32 hex encoded by default (16 bytes storage when transported as printable string) +// - Non configured, you don't need set a unique machine and/or data center id +// - K-ordered +// - Embedded time with 1 second precision +// - Unicity guaranted for 16,777,216 (24 bits) unique ids per second and per host/process +// +// Best used with xlog's RequestIDHandler (https://godoc.org/github.com/rs/xlog#RequestIDHandler). +// +// References: +// +// - http://www.slideshare.net/davegardnerisme/unique-id-generation-in-distributed-systems +// - https://en.wikipedia.org/wiki/Universally_unique_identifier +// - https://blog.twitter.com/2010/announcing-snowflake +package xid + +import ( + "crypto/md5" + "crypto/rand" + "database/sql/driver" + "encoding/binary" + "errors" + "fmt" + "os" + "sync/atomic" + "time" +) + +// Code inspired from mgo/bson ObjectId + +// ID represents a unique request id +type ID [rawLen]byte + +const ( + encodedLen = 20 // string encoded len + decodedLen = 15 // len after base32 decoding with the padded data + rawLen = 12 // binary raw len + + // encoding stores a custom version of the base32 encoding with lower case + // letters. + encoding = "0123456789abcdefghijklmnopqrstuv" +) + +// ErrInvalidID is returned when trying to unmarshal an invalid ID +var ErrInvalidID = errors.New("xid: invalid ID") + +// objectIDCounter is atomically incremented when generating a new ObjectId +// using NewObjectId() function. It's used as a counter part of an id. +// This id is initialized with a random value. +var objectIDCounter = randInt() + +// machineId stores machine id generated once and used in subsequent calls +// to NewObjectId function. +var machineID = readMachineID() + +// pid stores the current process id +var pid = os.Getpid() + +// dec is the decoding map for base32 encoding +var dec [256]byte + +func init() { + for i := 0; i < len(dec); i++ { + dec[i] = 0xFF + } + for i := 0; i < len(encoding); i++ { + dec[encoding[i]] = byte(i) + } +} + +// readMachineId generates machine id and puts it into the machineId global +// variable. If this function fails to get the hostname, it will cause +// a runtime error. +func readMachineID() []byte { + id := make([]byte, 3) + if hostname, err := os.Hostname(); err == nil { + hw := md5.New() + hw.Write([]byte(hostname)) + copy(id, hw.Sum(nil)) + } else { + // Fallback to rand number if machine id can't be gathered + if _, randErr := rand.Reader.Read(id); randErr != nil { + panic(fmt.Errorf("xid: cannot get hostname nor generate a random number: %v; %v", err, randErr)) + } + } + return id +} + +// randInt generates a random uint32 +func randInt() uint32 { + b := make([]byte, 3) + if _, err := rand.Reader.Read(b); err != nil { + panic(fmt.Errorf("xid: cannot generate random number: %v;", err)) + } + return uint32(b[0])<<16 | uint32(b[1])<<8 | uint32(b[2]) +} + +// New generates a globaly unique ID +func New() ID { + var id ID + // Timestamp, 4 bytes, big endian + binary.BigEndian.PutUint32(id[:], uint32(time.Now().Unix())) + // Machine, first 3 bytes of md5(hostname) + id[4] = machineID[0] + id[5] = machineID[1] + id[6] = machineID[2] + // Pid, 2 bytes, specs don't specify endianness, but we use big endian. + id[7] = byte(pid >> 8) + id[8] = byte(pid) + // Increment, 3 bytes, big endian + i := atomic.AddUint32(&objectIDCounter, 1) + id[9] = byte(i >> 16) + id[10] = byte(i >> 8) + id[11] = byte(i) + return id +} + +// FromString reads an ID from its string representation +func FromString(id string) (ID, error) { + i := &ID{} + err := i.UnmarshalText([]byte(id)) + return *i, err +} + +// String returns a base32 hex lowercased with no padding representation of the id (char set is 0-9, a-v). +func (id ID) String() string { + text := make([]byte, encodedLen) + encode(text, id[:]) + return string(text) +} + +// MarshalText implements encoding/text TextMarshaler interface +func (id ID) MarshalText() ([]byte, error) { + text := make([]byte, encodedLen) + encode(text, id[:]) + return text, nil +} + +// encode by unrolling the stdlib base32 algorithm + removing all safe checks +func encode(dst, id []byte) { + dst[0] = encoding[id[0]>>3] + dst[1] = encoding[(id[1]>>6)&0x1F|(id[0]<<2)&0x1F] + dst[2] = encoding[(id[1]>>1)&0x1F] + dst[3] = encoding[(id[2]>>4)&0x1F|(id[1]<<4)&0x1F] + dst[4] = encoding[id[3]>>7|(id[2]<<1)&0x1F] + dst[5] = encoding[(id[3]>>2)&0x1F] + dst[6] = encoding[id[4]>>5|(id[3]<<3)&0x1F] + dst[7] = encoding[id[4]&0x1F] + dst[8] = encoding[id[5]>>3] + dst[9] = encoding[(id[6]>>6)&0x1F|(id[5]<<2)&0x1F] + dst[10] = encoding[(id[6]>>1)&0x1F] + dst[11] = encoding[(id[7]>>4)&0x1F|(id[6]<<4)&0x1F] + dst[12] = encoding[id[8]>>7|(id[7]<<1)&0x1F] + dst[13] = encoding[(id[8]>>2)&0x1F] + dst[14] = encoding[(id[9]>>5)|(id[8]<<3)&0x1F] + dst[15] = encoding[id[9]&0x1F] + dst[16] = encoding[id[10]>>3] + dst[17] = encoding[(id[11]>>6)&0x1F|(id[10]<<2)&0x1F] + dst[18] = encoding[(id[11]>>1)&0x1F] + dst[19] = encoding[(id[11]<<4)&0x1F] +} + +// UnmarshalText implements encoding/text TextUnmarshaler interface +func (id *ID) UnmarshalText(text []byte) error { + if len(text) != encodedLen { + return ErrInvalidID + } + for _, c := range text { + if dec[c] == 0xFF { + return ErrInvalidID + } + } + decode(id, text) + return nil +} + +// decode by unrolling the stdlib base32 algorithm + removing all safe checks +func decode(id *ID, src []byte) { + id[0] = dec[src[0]]<<3 | dec[src[1]]>>2 + id[1] = dec[src[1]]<<6 | dec[src[2]]<<1 | dec[src[3]]>>4 + id[2] = dec[src[3]]<<4 | dec[src[4]]>>1 + id[3] = dec[src[4]]<<7 | dec[src[5]]<<2 | dec[src[6]]>>3 + id[4] = dec[src[6]]<<5 | dec[src[7]] + id[5] = dec[src[8]]<<3 | dec[src[9]]>>2 + id[6] = dec[src[9]]<<6 | dec[src[10]]<<1 | dec[src[11]]>>4 + id[7] = dec[src[11]]<<4 | dec[src[12]]>>1 + id[8] = dec[src[12]]<<7 | dec[src[13]]<<2 | dec[src[14]]>>3 + id[9] = dec[src[14]]<<5 | dec[src[15]] + id[10] = dec[src[16]]<<3 | dec[src[17]]>>2 + id[11] = dec[src[17]]<<6 | dec[src[18]]<<1 | dec[src[19]]>>4 +} + +// Time returns the timestamp part of the id. +// It's a runtime error to call this method with an invalid id. +func (id ID) Time() time.Time { + // First 4 bytes of ObjectId is 32-bit big-endian seconds from epoch. + secs := int64(binary.BigEndian.Uint32(id[0:4])) + return time.Unix(secs, 0) +} + +// Machine returns the 3-byte machine id part of the id. +// It's a runtime error to call this method with an invalid id. +func (id ID) Machine() []byte { + return id[4:7] +} + +// Pid returns the process id part of the id. +// It's a runtime error to call this method with an invalid id. +func (id ID) Pid() uint16 { + return binary.BigEndian.Uint16(id[7:9]) +} + +// Counter returns the incrementing value part of the id. +// It's a runtime error to call this method with an invalid id. +func (id ID) Counter() int32 { + b := id[9:12] + // Counter is stored as big-endian 3-byte value + return int32(uint32(b[0])<<16 | uint32(b[1])<<8 | uint32(b[2])) +} + +// Value implements the driver.Valuer interface. +func (id ID) Value() (driver.Value, error) { + b, err := id.MarshalText() + return string(b), err +} + +// Scan implements the sql.Scanner interface. +func (id *ID) Scan(value interface{}) (err error) { + switch val := value.(type) { + case string: + return id.UnmarshalText([]byte(val)) + case []byte: + return id.UnmarshalText(val) + default: + return fmt.Errorf("xid: scanning unsupported type: %T", value) + } +}