😄 Go common utility functions
Inspired by https://github.com/kjk/u
FUNCTIONS
func B64Decode(input string) ([]byte, error)
B64Decode try to decode an input string and returns bytes if success.
func B64Encode(input []byte) string
B64Encode returns a base64 encoded string of input bytes.
func BoolPtr(val bool) *bool
BoolPtr returns a pointer to a bool of value 'val'.
func CaptureStderr() (func() string, error)
CaptureStderr temporarily pipes os.Stderr into a buffer.
func CaptureStdout() (func() string, error)
CaptureStdout temporarily pipes os.Stdout into a buffer.
func CaptureStdoutAndStderr() (func() string, error)
CaptureStdoutAndStderr temporarily pipes os.Stdout and os.Stderr into a
buffer.
func CheckErr(err error)
CheckErr panics if the passed error is not nil.
func CombineFuncs(left func(), right ...func()) func()
CombineFuncs create a chain of functions. This can be particularly useful
for creating cleanup function progressively. It solves the infinite loop you
can have when trying to do it manually:
https://play.golang.org/p/NQem8UJ500t.
func CommandExists(command string) bool
CommandExists checks whether a command is available in the $PATH.
func CreateEmptyFileWithSize(path string, size uint) error
CreateEmptyFileWithSize creates a new file of the desired size, filled with
zeros.
func CurrentUsername(fallback string) string
CurrentUsename returns the current user's username. If username cannot be
retrieved, it returns the passed fallback.
func DirExists(path string) bool
DirExists checks whether a path exists and is a directory.
func ExecStandaloneOutputs(cmd *exec.Cmd) ([]byte, []byte, error)
ExecStandaloneOutputs runs the command and returns its standard output and
standard error.
func ExpandPath(path string) (string, error)
ExpandPath performs various expansions on a given path.
- Replaces ~/ with $HOME/. - Returns absolute path. - Expands env vars.
TODO: - Follow symlinks.
func FanIn(chans ...<-chan interface{}) <-chan interface{}
FanIn merges multiple input chans events into one.
func FileExists(path string) bool
FileExists checks whether a path exists and is a regular file.
func Future(fn func() (interface{}, error)) <-chan FutureRet
Future starts running the given function in background and return a chan
that will return the result of the execution.
func IsASCII(buf []byte) bool
IsASCII checks whether a buffer only contains ASCII characters.
func IsBinary(buf []byte) bool
IsBinary returns whether the provided buffer looks like binary or
human-readable.
It is inspired by the implementation made in the Git project.
https://github.com/git/git/blob/49f38e2de47a401fc2b0f4cce38e9f07fb63df48/xdiff-interface.c#L188.
func JSON(input interface{}) string
JSON returns a JSON representation of the passed input.
func MustCaptureStderr() func() string
MustCaptureStderr wraps CaptureStderr and panics if initialization fails.
func MustCaptureStdout() func() string
MustCaptureStdout wraps CaptureStdout and panics if initialization fails.
func MustCaptureStdoutAndStderr() func() string
MustCaptureStdoutAndStderr wraps CaptureStdoutAndStderr and panics if
initialization fails.
func MustExpandPath(path string) string
MustExpandPath wraps ExpandPath and panics if initialization fails.
func MustTempFileName(dir, pattern string) string
MustTempFileName wraps TempFileName and panics if initialization fails.
func MustTempfileWithContent(content []byte) (*os.File, func())
MustTempfileWithContent wraps TempfileWithContent and panics if
initialization fails.
func PathExists(path string) bool
PathExists checks whether a path exists or not.
func PrettyJSON(input interface{}) string
PrettyJSON returns an indented JSON representation of the passed input.
func RandomLetters(n int) string
RandomLetters returns a string containing 'n' random letters.
func SafeExec(cmd *exec.Cmd) string
SafeExec runs a command and return a string containing the combined standard
output and standard error. If the program fails, the result of `err` is
appended to the output.
func Sha1(data []byte) []byte
func Sha1Hex(data []byte) string
func ShortDuration(d time.Duration) string
ShortDuration returns a short human-friendly representation of a duration.
For duration < 100 days, the output length will be <= 7.
func SilentClose(closer io.Closer)
SilentClose calls an io.Closer.Close() function and ignore potential errors.
You can use it as `defer SilenceClose(f)`
func TempFileName(dir, pattern string) (string, error)
TempFileName returns a valid temporary file name (the file is not created).
func TempfileWithContent(content []byte) (*os.File, func(), error)
TempfileWithContent creates a tempfile with specified content written in it,
it also seeks the file pointer so you can read it directly. The second
returned parameter is a cleanup function that closes and removes the temp
file.
func UniqueInterfaces(input []interface{}) []interface{}
UniqueInterfaces removes duplicate values from an interface slice.
func UniqueInts(input []int) []int
UniqueInts removes duplicate values from an int slice.
func UniqueStrings(input []string) []string
UniqueStrings removes duplicate values from a string slice.
func Unzip(src string, dest string) ([]string, error)
Unzip decompresses a zip archive, moving all files and folders within the
zip file to an output directory. Based on
https://golangcode.com/unzip-files-in-go/ (MIT).
func UnzipBytes(src []byte, dest string) ([]string, error)
UnzipBytes is similar to Unzip but takes a zip archive as bytes instead of
looking for a real file.
func WaitForCtrlC()
TYPES
type FutureRet struct {
Ret interface{}
Err error
}
FutureRet is a generic struct returned by Future.
type MutexMap struct {
// Has unexported fields.
}
MutexMap manages a pool of mutexes that can be get by key. MutexMap is
thread-safe.
func (mm *MutexMap) Lock(key string) func()
Lock locks a mutex by key, and returns a callback for unlocking unlock. Lock
will automatically create a new mutex for new keys.
func (mm *MutexMap) RLock(key string) func()
RLock locks a mutex by key for reading, and returns a callback for unlocking
unlock. RLock will automatically create a new mutex for new keys.
type UniqueChild interface {
SetChild(childFn func(context.Context))
CloseChild()
}
UniqueChild is a goroutine manager (parent) that can only have one child at
a time. When you call UniqueChild.SetChild(), UniqueChild cancels the
previous child context (if any), then run a new child. The child needs to
auto-kill itself when its context is done.
func NewUniqueChild(ctx context.Context) UniqueChild
NewUniqueChild instantiates and returns a UniqueChild manager.
See
$ go get moul.io/ubenchmark iter time/iter
--------- ---- ---------
BenchmarkUnzip-8 4101 251654.00 ns/op
BenchmarkUnzipBytes-8 4842 213715.00 ns/op
BenchmarkB64Encode/1-8 30219784 38.44 ns/op
BenchmarkB64Encode/1-parallel-8 120309013 10.42 ns/op
BenchmarkB64Encode/1000-8 962917 1256.00 ns/op
BenchmarkB64Encode/1000-parallel-8 1627962 815.00 ns/op
BenchmarkB64Encode/1000000-8 1094 1092692.00 ns/op
BenchmarkB64Encode/1000000-parallel-8 3328 364672.00 ns/op
BenchmarkB64Decode/1000-8 1000000 1091.00 ns/op
BenchmarkB64Decode/1000-parallel-8 1971834 598.80 ns/op
BenchmarkB64Decode/10000-8 131664 8624.00 ns/op
BenchmarkB64Decode/10000-parallel-8 274162 4768.00 ns/op
BenchmarkB64Decode/100000-8 15345 77537.00 ns/op
BenchmarkB64Decode/100000-parallel-8 32480 34873.00 ns/op
BenchmarkIsBinary/small-valid-8 173952991 6.74 ns/op
BenchmarkIsBinary/small-valid-parallel-8 836416648 1.45 ns/op
BenchmarkIsBinary/long-valid-8 1916740 625.70 ns/op
BenchmarkIsBinary/long-valid-parallel-8 8315928 149.70 ns/op
BenchmarkIsBinary/small-invalid-8 170598688 7.08 ns/op
BenchmarkIsBinary/small-invalid-parallel-8 783116866 1.72 ns/op
BenchmarkCommandExists/go-8 145177 8699.00 ns/op
BenchmarkCommandExists/go-parallel-8 278449 4384.00 ns/op
BenchmarkCommandExists/asddsa-8 38422 32856.00 ns/op
BenchmarkCommandExists/asddsa-parallel-8 69381 18171.00 ns/op
BenchmarkSafeExec-8 92 11439103.00 ns/op
BenchmarkIsASCII-8 227565444 5.34 ns/op
BenchmarkCombineFuncs-8 23210830 52.56 ns/op
BenchmarkFuture-8 4820587 263.70 ns/op
BenchmarkRandomLetters/1000-8 783525 1572.00 ns/op
BenchmarkRandomLetters/1000-parallel-8 91543 12743.00 ns/op
BenchmarkRandomLetters/10000-8 81429 14677.00 ns/op
BenchmarkRandomLetters/10000-parallel-8 9618 127306.00 ns/op
BenchmarkRandomLetters/100000-8 8164 148755.00 ns/op
BenchmarkRandomLetters/100000-parallel-8 914 1299007.00 ns/op
BenchmarkUniqueStrings/slice1-8 2245912 553.70 ns/op
BenchmarkUniqueStrings/slice1-parallel-8 5644569 357.00 ns/op
BenchmarkUniqueStrings/slice2-8 9151 114607.00 ns/op
BenchmarkUniqueStrings/slice2-parallel-8 20236 55601.00 ns/op
BenchmarkUniqueInts/slice1-8 3188648 371.30 ns/op
BenchmarkUniqueInts/slice1-parallel-8 9704232 117.50 ns/op
BenchmarkUniqueInts/slice2-8 16548 66907.00 ns/op
BenchmarkUniqueInts/slice2-parallel-8 57608 21750.00 ns/op
BenchmarkUniqueInterfaces/slice1-8 1480366 962.20 ns/op
BenchmarkUniqueInterfaces/slice1-parallel-8 4402994 261.30 ns/op
BenchmarkUniqueInterfaces/slice2-8 4614 254938.00 ns/op
BenchmarkUniqueInterfaces/slice2-parallel-8 10000 125025.00 ns/op
BenchmarkShortDuration/Simple-8 23745075 47.64 ns/op
BenchmarkShortDuration/Simple-parallel-8 100000000 11.24 ns/op
BenchmarkShortDuration/Complex-8 4912780 231.40 ns/op
BenchmarkShortDuration/Complex-parallel-8 13411066 75.40 ns/op
BenchmarkBoolPtr/serial-8 1000000000 0.32 ns/op
BenchmarkBoolPtr/parallel-8 1000000000 0.28 ns/op
benchmark iter time/iter
--------- ---- ---------
BenchmarkUnzip-12 4551 264133.00 ns/op
BenchmarkUnzipBytes-12 4507 243344.00 ns/op
BenchmarkB64Encode/1-12 16033570 80.95 ns/op
BenchmarkB64Encode/1-parallel-12 59893237 17.48 ns/op
BenchmarkB64Encode/1000-12 379872 4646.00 ns/op
BenchmarkB64Encode/1000-parallel-12 1243312 945.10 ns/op
BenchmarkB64Encode/1000000-12 315 4063088.00 ns/op
BenchmarkB64Encode/1000000-parallel-12 2054 597679.00 ns/op
BenchmarkB64Decode/1000-12 424038 3637.00 ns/op
BenchmarkB64Decode/1000-parallel-12 1633958 732.70 ns/op
BenchmarkB64Decode/10000-12 33224 35140.00 ns/op
BenchmarkB64Decode/10000-parallel-12 200544 6350.00 ns/op
BenchmarkB64Decode/100000-12 4921 326188.00 ns/op
BenchmarkB64Decode/100000-parallel-12 24049 49786.00 ns/op
BenchmarkIsBinary/small-valid-12 123109468 9.29 ns/op
BenchmarkIsBinary/small-valid-parallel-12 747959686 1.54 ns/op
BenchmarkIsBinary/long-valid-12 5283378 240.30 ns/op
BenchmarkIsBinary/long-valid-parallel-12 26021748 41.87 ns/op
BenchmarkIsBinary/small-invalid-12 130593402 9.19 ns/op
BenchmarkIsBinary/small-invalid-parallel-12 662583970 1.57 ns/op
BenchmarkCommandExists/go-12 132699 9937.00 ns/op
BenchmarkCommandExists/go-parallel-12 593409 1715.00 ns/op
BenchmarkCommandExists/asddsa-12 24820 52140.00 ns/op
BenchmarkCommandExists/asddsa-parallel-12 130977 8541.00 ns/op
BenchmarkSafeExec-12 644 2378627.00 ns/op
BenchmarkCombineFuncs-12 6741579 204.20 ns/op
BenchmarkFuture-12 1504198 780.20 ns/op
BenchmarkRandomLetters/1000-12 286212 4019.00 ns/op
BenchmarkRandomLetters/1000-parallel-12 40786 29071.00 ns/op
BenchmarkRandomLetters/10000-12 29296 40241.00 ns/op
BenchmarkRandomLetters/10000-parallel-12 4363 286588.00 ns/op
BenchmarkRandomLetters/100000-12 3165 400320.00 ns/op
BenchmarkRandomLetters/100000-parallel-12 421 2877871.00 ns/op
BenchmarkUniqueStrings/slice1-12 963402 1430.00 ns/op
BenchmarkUniqueStrings/slice1-parallel-12 4290940 307.50 ns/op
BenchmarkUniqueStrings/slice2-12 6712 246924.00 ns/op
BenchmarkUniqueStrings/slice2-parallel-12 21454 56186.00 ns/op
BenchmarkUniqueInts/slice1-12 1453717 834.20 ns/op
BenchmarkUniqueInts/slice1-parallel-12 7538754 144.30 ns/op
BenchmarkUniqueInts/slice2-12 10000 146356.00 ns/op
BenchmarkUniqueInts/slice2-parallel-12 61899 20556.00 ns/op
BenchmarkUniqueInterfaces/slice1-12 911822 1778.00 ns/op
BenchmarkUniqueInterfaces/slice1-parallel-12 3223353 360.10 ns/op
BenchmarkUniqueInterfaces/slice2-12 2418 564324.00 ns/op
BenchmarkUniqueInterfaces/slice2-parallel-12 7670 140357.00 ns/op
BenchmarkShortDuration/Simple-12 13385139 98.24 ns/op
BenchmarkShortDuration/Simple-parallel-12 59156300 18.38 ns/op
BenchmarkShortDuration/Complex-12 2444396 486.20 ns/op
BenchmarkShortDuration/Complex-parallel-12 9201567 132.90 ns/op
I really welcome contributions. Your input is the most precious material. I'm well aware of that and I thank you in advance. Everyone is encouraged to look at what they can do on their own scale; no effort is too small.
Everything on contribution is sum up here: CONTRIBUTING.md
Thanks goes to these wonderful people (emoji key):
 Manfred Touron 🚧 📖 |
 moul-bot 🚧 |
 Darko Djalevski 💻 |
This project follows the all-contributors specification. Contributions of any kind welcome!
© 2020-2021 Manfred Touron
Licensed under the Apache License, Version 2.0 (LICENSE-APACHE) or the MIT license (LICENSE-MIT), at your option. See the COPYRIGHT file for more details.
SPDX-License-Identifier: (Apache-2.0 OR MIT)
