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 CallFunc // 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" "fmt" ) // 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" }); err != nil { fmt.Printf("%v\n", err) } }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.