golibs

golibs

golang functions (to be included in other projects)

go get -u -t simonwaldherr.de/go/golibs/...

coverage & tests

go test ./...

.	.	service	info
			go test ./...
		travis-ci.org	test on various go versions
		appveyor.com	test under windows
		semaphoreci.com	yet another ci service
		wercker.com	the wercker ci service
	goreportcard.com	report card
	codebeat.co	code quality
	codacy.com	code quality
	bettercodehub.com	code quality
	coveralls.io	test coverage
		go tool cover
	fossa.io	license report
		free + open source license
	flattr.com	micro donation
	godoc.org	documentation

each new build gets tested in multiple steps:

• on development i regularly type go test from time to time to check the test suite
• also there are a few go apps in the examples-folder which i test to build and run
• on commit, git automatically runs the pre-commit-hook shell script
• after a commit gets pushed to GitHub, the following tests are started via Webhooks and Services
  • Travis CI build the lib and all tests on docker containers with the go versions noted in .travis.yml
  • appveyor builds the lib on Windows Server to test against the Microsoft Infrastructure (.appveyor.yml)
  • magnum-ci, another ci service build the lib and tests on a linux (ubuntu) machine
  • semaphoreci, yet another (linux (ubuntu) based) ci service

ToC

• ansi can print colored and styled text to your terminal
• arg simplifies cli flags (arguments)
• as can convert most standard data types to most other data types
• cache is an easy and small caching package
• cachedfile simplifies reading and writing from and to disk and adds caching
• channel simplifies channel operations, e.g. sending the same data to multiple receivers
• csv load and parse CSV file
• file wraps around the standard functions to simplify reading and writing on disk
• foreach calls a given function for each element of a [ JSON-string ]
• gcurses enabling the development of text user interface applications
• gopath provides an easy way to get system information
• graphics can manipulate images
• http make easy and fast HTTP(S) requests
• log helps on logging your applications status
• re helps you whenever you have to do something multiple times
• regex is a layer to speed up your regular expression development
• rss is a rss feed parser based on Golangs std xml package
• ssl generates ssl certificates for https
• stack can store your values in stacks and rings
• structs use structs like maps
• xmath provides a few mathematical functions like Sum, Median, Harmonic-mean, …
• xtime xtime implements a subset of strftime

WARNING

some functions in this repo enables you to write really bad code - I wrote it anyway because:

• sometimes you need a quick and dirty solution
• it shows you possible ways, feel free to fork and customize
• mostly bad go code is better than good php code - every aspect in golang is designed to prevent from bad code

BUT: please remember that you can do things more performantly e.g. converting a string to a float is much faster done with strconv.ParseFloat than with as.Float.

sublibs

ansi -

import "simonwaldherr.de/go/golibs/ansi"

ansi can print colored and styled text to your terminal:

• green, yellow and red strings:

log.Println(ansi.Color("INFO: everything is fine", ansi.Green))
log.Println(ansi.Color("WARNING: not everything is fine", ansi.Yellow))
log.Println(ansi.Color("ERROR: OMG!!!", ansi.Red))

• bold and underlined text:

fmt.Printf("this is %v and %v text", ansi.Bold("bold"), ansi.Underline("underlined"))

arg -

import "simonwaldherr.de/go/golibs/arg"

the arg package simplifies cli flags (arguments)

as -

import "simonwaldherr.de/go/golibs/as"

with as you can convert most standard data types to most other data types e.g.

• int to string:

var x string = as.String(int(32))

• string to int:

var x int = as.Int("32")

• string to time:

var x time.Time = as.Time("31.12.2014")

cache -

import "simonwaldherr.de/go/golibs/cache"

cachedfile -

import "simonwaldherr.de/go/golibs/cachedfile"

cachedfile simplifies reading and writing from and to disk and adds caching

do

str := "Neque porro quisquam est, qui dolorem ipsum, quia dolor sit, amet, consectetur, adipisci velit."
err := cachedfile.Write("filename.txt", str, false)

and in less then 15 minutes this

str, _ := cachedfile.Read("filename.txt")

and there will be no file access to disk. If you kill the App, wait 15 min or call cachedfile.Stop() the cached content will be exported to disk.

channel -

import "simonwaldherr.de/go/golibs/channel"

channel simplifies channel operations, e.g. sending the same data to multiple receivers

con := channel.Init()

receiver01 := con.AddReceiver()
receiver02 := con.AddReceiver()
receiver03 := con.AddReceiver()

go func() {
  fmt.Println(<-receiver01)
}()

go func() {
  fmt.Println(<-receiver02)
}()

go func() {
  fmt.Println(<-receiver03)
}()

transmitter01 := con.AddTransmitter()

transmitter01 <- "Hello World"

csv -

import "simonwaldherr.de/go/golibs/csv"

file -

import "simonwaldherr.de/go/golibs/file"

file wraps around the standard functions to simplify reading and writing on disk

str := "Neque porro quisquam est, qui dolorem ipsum, quia dolor sit, amet, consectetur, adipisci velit."
err := file.Write("filename.txt", str, false)

Besides simple reading and writing, the package also contains functions to test file statuses, read large files by small blocks, clear, rename and delete files. There is even a function for do things with each file in a directory (even with subfolders):

err := file.Each("..", true, func(filename, extension, filepath string, dir bool, fileinfo os.FileInfo) {
	if extension == "go" && !dir {
		t.Logf("%v, %v, %v, %v\n", filename, filepath, dir, fileinfo)
	}
}

If you need the absolute path to a file, but only have a relative path, you can use file.GetAbsolutePath("~/path/to/file.txt").

foreach -

import "simonwaldherr.de/go/golibs/foreach"

foreach calls a given function for each element of a [ JSON-string ]

gcurses -

import "simonwaldherr.de/go/golibs/gcurses"

gcurses is a terminal control library for Unixoide systems, enabling the development of text user interface applications.

Named after the "GUI-like" terminal application toolkit ncurses (new curses) which is named after the original curses. This library is in a very early stage.

package main

import (
  "fmt"
  "simonwaldherr.de/go/golibs/gcurses"
  "time"
)

func main() {
  writer := gcurses.New()

  writer.Start()

  for i := 0; i < 100; i++ {
    fmt.Fprintf(writer, "Count till one hundred: %d\nStill counting ...\n", i)
    time.Sleep(time.Millisecond * 10)
  }

  time.Sleep(time.Millisecond * 500)
  fmt.Fprintln(writer, "Finished counting")

  writer.Stop()
}

gopath -

import "simonwaldherr.de/go/golibs/gopath"

gopath provides an easy way to get system information

to read a config file in which is in the same file as the executable, you can do something like this:

package main

import (
  "fmt"
  "path/filepath"
  "simonwaldherr.de/go/golibs/file"
  "simonwaldherr.de/go/golibs/gopath"
)

func main() {
  dir := gopath.Dir()
  config := file.Read(filepath.Join(dir, "config.yaml"))
  
  ...

graphics -

import "simonwaldherr.de/go/golibs/graphics"

with graphics you can manipulate images

img := graphics.EachPixel(file, func(r, g, b, a uint8) (uint8, uint8, uint8, uint8) {
	return g, b, r, a
})

http -

import "simonwaldherr.de/go/golibs/http"

log -

import "simonwaldherr.de/go/golibs/log"

re -

import "simonwaldherr.de/go/golibs/re"

re helps you whenever you have to do something multiple times

data, stop := re.Do(time.Second * 5, func(data chan<- interface{}) {
	data <- fmt.Sprintf("%v\n", time.Now().Format("02.01.2006 15:04:05"))
})

regex -

import "simonwaldherr.de/go/golibs/regex"

regex is a layer to speed up your regular expression development

str, err := regex.ReplaceAllString("Ipsum Lorem", "([^ ]+) ([^ ]+)", "$2 $1")

rss -

import "simonwaldherr.de/go/golibs/rss"

rss is a rss feed parser based on Golangs std xml package

podcast, err := rss.Read(url)
if err == nil {
  for _, episode := range podcast.Items {
    fmt.Println(episode.Title)
  }
}

ssl -

import "simonwaldherr.de/go/golibs/ssl"

ssl generates ssl certificates for https

err := ssl.Generate(options)

stack -

import "simonwaldherr.de/go/golibs/stack"

with stack you can store your values in stacks and rings

array := stack.Lifo()
array.Push(as.Bytes(12.34))
array.Push(as.Float(13.37))
array.Push(as.String(23.0))
for array.Len() > 0 {
	log.Println(array.Pop())
}

structs -

import "simonwaldherr.de/go/golibs/structs"

xmath -

import "simonwaldherr.de/go/golibs/xmath"

xmath provides a few mathematical functions like Max, Min, Sum, Median, Harmonic-mean, ...

var f = []float64{.5, 1.33, 2.66, 3.99, 13.37, 23.42, 42.000003}

fmt.Printf("Max: %v\n", xmath.Max(f))
fmt.Printf("Min: %v\n", xmath.Min(f))
fmt.Printf("Sum: %v\n", xmath.Sum(f))

fmt.Printf("Median:     %v\n", xmath.Median(f))
fmt.Printf("Arithmetic: %v\n", xmath.Arithmetic(f))
fmt.Printf("Harmonic:   %v\n", xmath.Harmonic(f))
fmt.Printf("Geometric:  %v\n", xmath.Geometric(f))

xtime -

import "simonwaldherr.de/go/golibs/xtime"

xtime implements a subset of strftime

t, _ := time.Now()
fmt.Println(xtime.Fmt("%Y-%m-%d %H:%M:%S", t))