golpal

README

Golpal

Easy to use Golang Eval Library

Introduction

Golpal is simple library to allow developer to do eval operation on golang source codes. Technically Golang doesn't provide API to do some eval, so we use temporary file to achieve that.

Installation

Stable version: v1.0.0

Just go get the lib is enough

go get -u github.com/novalagung/golpal

Run test

cd $GOPATH/src/github.com/novalagung/golpal
go test *.go -v

Example

Simple Example

package main

import "github.com/novalagung/golpal"
import "fmt"

func main() {
	cmdString := `3 + 2`
	output, err := golpal.New().ExecuteSimple(cmdString)
	if err != nil {
		fmt.Println(err)
	}
	fmt.Println("result", "=>", output)
}

For one line statement using ExecuteSimple(), return keyword is optional

Another Example

cmdString := `
	number := 3
	if number == 2 {
		return "wrong"
	} else {
		return "right"
	}
`

output, err := golpal.New().ExecuteSimple(cmdString)
if err != nil {
	fmt.Println(err)
}
fmt.Println("result", "=>", output)

For multiline statement using ExecuteSimple(), return must be defined

Example which use strings and runtime

cmdString := `
	osName := runtime.GOOS
	arr := []string{"my", "operation system", "is", osName}
	return strings.Join(arr, ", ")
`

output, err := golpal.New().AddLibs("strings", "runtime").ExecuteSimple(cmdString)
if err != nil {
	fmt.Println(err)
}
fmt.Println("result", "=>", output)

Example Not Simple (again, NOT SIMPLE, by using Execute() func)

cmdString := `
	func calculate(values ...int) int {
		total := 0
		for _, each := range values {
			total = total + each
		}
		return total
	}

	func main() {
		res := calculate(1, 2, 3, 4, 2, 3, 1)
		fmt.Printf("total : %d", res)
	}
`

output, err := golpal.New().Execute(cmdString)
if err != nil {
	fmt.Println(err)
}
fmt.Println("result", "=>", output)

Example Execute Raw (use ExecuteRaw() func)

cmdString := `
	package main

	import "fmt"

	func main() {
		fmt.Print("hello")
	}
`

output, err := golpal.New().ExecuteRaw(cmdString)
if err != nil {
	fmt.Println(err)
}
fmt.Println("result", "=>", output)

More Example

For more examples please take a look at the golpal_test.go file.

API Reference

Func of golpal

There are only one func available, golpal.New() which return object that type is *golpal.Golpal

Func	Usage
golpal.New()	instantiate new *golpal.Golpal object

Properties of *golpal.Golpal

Property	Type	Usage
.WillDeleteTemporaryFile	bool	Determine if temporary path will be deleted or not after executing the source codes (default is true)
.TemporaryFolderName	string	Name of temporary folder used to store all *.go temp files (default is .temp for *nix / *drwin, and temp for w*ndows)

Methods of *golpal.Golpal

Method	Usage
.AddLibs(libs ...string)	Add other libraries, by default only fmt is included
.ExecuteSimple(cmdString string)	Run golang source codes. The code will be placed inside virtual main() func. This function doesn't allow fmt.Print*(). Also for multiline statement, return must be defined
.Execute(cmdString string)	Run golang source codes which contains main() func
.ExecuteRaw(cmdString string)	Run complete golang source code
.DeleteTemporaryPath()	Force delete temporary path which used to do the exec process

Contribution

Feel free to contribute

fork -> commit -> push -> pull request

License

MIT License

Author

Noval Agung Prayogo - http://novalagung.com/

Documentation

Index

• Constants
• type Golpal
  • func New() *Golpal
  • func (g *Golpal) AddLibs(libs ...string) *Golpal
  • func (g *Golpal) DeleteTemporaryPath()
  • func (g *Golpal) Execute(cmdString string) (string, error)
  • func (g *Golpal) ExecuteRaw(cmdString string) (string, error)
  • func (g *Golpal) ExecuteSimple(cmdString string) (string, error)

Constants

const (
	Version = "v1.0.0"
)

Types

type Golpal

type Golpal struct {
	WillDeleteTemporaryFile bool
	TemporaryFolderName     string
	// contains filtered or unexported fields
}

func New

func New() *Golpal

func (*Golpal) AddLibs

func (g *Golpal) AddLibs(libs ...string) *Golpal

func (*Golpal) DeleteTemporaryPath

func (g *Golpal) DeleteTemporaryPath()

func (*Golpal) Execute

func (g *Golpal) Execute(cmdString string) (string, error)

func (*Golpal) ExecuteRaw

func (g *Golpal) ExecuteRaw(cmdString string) (string, error)

func (*Golpal) ExecuteSimple

func (g *Golpal) ExecuteSimple(cmdString string) (string, error)