QuickJS is a small and embeddable Javascript engine written by Fabrice Bellard.
go-quickjs is a package wrapping quickjs and making it a pragmatic embeddable language.
With some helper functions provided by go-quickjs, calling Golang functions from Javascript,
or calling Javascript functions from Golang are both very simple. So, with the help of go-quickjs, quickjs
can be embedded in Golang application easily.
The package is fully go-getable, So, just type
go get github.com/rosbit/go-quickjs
to install.
package main
import (
"github.com/rosbit/go-quickjs"
"fmt"
)
func main() {
ctx, err := quickjs.NewContext()
if err != nil {
fmt.Printf("%v\n", err)
return
}
res, _ := ctx.Eval("a + b", map[string]interface{}{
"a": 10,
"b": 1,
})
fmt.Println("result is:", res)
}Suppose there's a Javascript file named a.js like this:
function add(a, b) {
return a+b
}one can call the Javascript function add() in Go code like the following:
package main
import (
"github.com/rosbit/go-quickjs"
"fmt"
)
var add func(int, int)int
func main() {
ctx, err := quickjs.NewContext()
if err != nil {
fmt.Printf("%v\n", err)
return
}
if _, err := ctx.EvalFile("a.js", nil); err != nil {
fmt.Printf("%v\n", err)
return
}
// method 1: bind JS function with a golang var
if err := ctx.BindFunc("add", &add); err != nil {
fmt.Printf("%v\n", err)
return
}
res := add(1, 2)
// method 2: call JS function using Call
res, err := ctx.CallFunc("add", 1, 2)
if err != nil {
fmt.Printf("%v\n", err)
return
}
fmt.Println("result is:", res)
}Javascript calling Go function is also easy. In the Go code, make a Golang function
as Javascript global function by calling EvalFile by registering. There's the example:
package main
import "github.com/rosbit/go-quickjs"
// function to be called by Javascript
func adder(a1 float64, a2 float64) float64 {
return a1 + a2
}
func main() {
ctx, err := quickjs.NewContext()
if err != nil {
fmt.Printf("%v\n", err)
return
}
if _, err := ctx.EvalFile("b.js", map[string]interface{}{
"adder": adder,
}) // b.js containing code calling "adder"
}In Javascript code, one can call the registered function directly. There's the example b.js.
r = adder(1, 100) // the function "adder" is implemented in Go
console.log(r)The package is not fully tested, so be careful.
Pull requests are welcome! Also, if you want to discuss something send a pull request with proposal and changes. Convention: fork the repository and make changes on your fork in a feature branch.