util

Documentation

Index

• func BytesToString(b []byte) string
• func CharSpliter(data []byte, atEOF bool) (advance int, token []byte, err error)
• func CheckErr(err error)
• func CombineError(fns ...func() error) error
• func Contains[T comparable](slice []T, elem T) bool
• func Depointer[T comparable](t *T) T
• func Deref[T any](p *T) T
• func DerefOr[T any](p *T, defaultVal T) T
• func FileExists(filename string) bool
• func GetFdFromConn(c net.Conn) int
• func GetFdFromListener(l net.Listener) int
• func GetFunctionName(x any) string
• func HandleErr(err error, notExit ...bool)
• func IndexedUUID() string
• func IsConnClosed(err error) bool
• func NoError(fn func() error) error
• func ParseScheme(req *http.Request) string
• func Ping(ip string, timeout time.Duration) (bool, error)
• func Pointer[T comparable](t T) *T
• func RequestID() string
• func Round[T float32 | float64](value T, precision uint) T
• func RunOrDie(fn func() error)
• func SafePointer[T any](v T) T
• func SplitByDoublePipe(data []byte, atEOF bool) (advance int, token []byte, err error)
• func StringAny(x any) string
• func StringToBytes(s string) []byte
• func Tcping(host string, port int, timeout time.Duration) bool
• func UUID(prefix ...string) string
• func ValueOf[T any](v T) *T
• type Connection
  • func GetConnection(conn net.Conn) Connection

Examples

• Round

Functions

func BytesToString

func BytesToString(b []byte) string

BytesToString converts byte slice to string without a memory allocation. For more details, see https://github.com/golang/go/issues/53003#issuecomment-1140276077.

func CharSpliter

func CharSpliter(data []byte, atEOF bool) (advance int, token []byte, err error)

CharSpliter is the custom split function for bufio.Scanner.

func CheckErr

func CheckErr(err error)

CheckErr just check error and print it.

func CombineError

func CombineError(fns ...func() error) error

CombineError combine error from fns.

func Contains

func Contains[T comparable](slice []T, elem T) bool

Contains check T in slice.

func Depointer

func Depointer[T comparable](t *T) T

Depointer will return a T with given value.

func Deref

func Deref[T any](p *T) T

Deref returns the value pointed to by the pointer. If the pointer is nil, returns the zero value for the type.

func DerefOr

func DerefOr[T any](p *T, defaultVal T) T

DerefOr returns the value pointed to by the pointer. If the pointer is nil, returns the default value.

func FileExists

func FileExists(filename string) bool

FileExists check file exists.

func GetFdFromConn

func GetFdFromConn(c net.Conn) int

GetFdFromConn get net.Conn's file descriptor.

func GetFdFromListener

func GetFdFromListener(l net.Listener) int

GetFdFromListener get net.Listener's file descriptor.

func GetFunctionName

func GetFunctionName(x any) string

func HandleErr

func HandleErr(err error, notExit ...bool)

HandleErr will call os.Exit() when any error encountered.

func IndexedUUID

func IndexedUUID() string

func IsConnClosed

func IsConnClosed(err error) bool

func NoError

func NoError(fn func() error) error

NoError call fn and always return nil.

func ParseScheme

func ParseScheme(req *http.Request) string

func Ping

func Ping(ip string, timeout time.Duration) (bool, error)

Ping work like command `ping`. If target ip is reachable, return true, nil, If target ip is unreachable, return false, nil, If error encountered, return false, error. More usage see tests in `pkg/util/util_test.go`.

func Pointer

func Pointer[T comparable](t T) *T

Pointer will return a pointer to T with given value.

func RequestID

func RequestID() string

func Round

func Round[T float32 | float64](value T, precision uint) T

Round returns a rounded version of x with a specified precision.

The precision parameter specifies the number of decimal places to round to. Round uses the "round half away from zero" rule to break ties.

Examples:

Round(3.14159, 2) returns 3.14
Round(3.14159, 1) returns 3.1
Round(-3.14159, 1) returns -3.1

Example

fmt.Printf("%.3f\n", Round(3.14159, 3))
fmt.Printf("%.2f\n", Round(2.71828, 2))
fmt.Printf("%.1f\n", Round(-3.14159, 1))

Output:

3.142
2.72
-3.1

func RunOrDie

func RunOrDie(fn func() error)

RunOrDie will panic when error encountered.

func SafePointer

func SafePointer[T any](v T) T

func SplitByDoublePipe

func SplitByDoublePipe(data []byte, atEOF bool) (advance int, token []byte, err error)

SplitByDoublePipe is the custom split function for bufio.Scanner.

func StringAny

func StringAny(x any) string

StringAny format anything to string.

func StringToBytes

func StringToBytes(s string) []byte

StringToBytes convers string to byte slice without a memory allocation. For more details, see https://github.com/golang/go/issues/53003#issuecomment-1140276077.

func Tcping

func Tcping(host string, port int, timeout time.Duration) bool

_tcping work like command `tcping`.

func UUID

func UUID(prefix ...string) string

func ValueOf

func ValueOf[T any](v T) *T

ValueOf returns a pointer to the given value

Types

type Connection

type Connection struct {
	RemoteIP   string
	LocalIP    string
	RemotePort int
	LocalPort  int
}

func GetConnection

func GetConnection(conn net.Conn) Connection