full-stack go with gopherjs
TRANSCRIPT
Full-Stack Go with GopherJSPogaKKTIX
Let's talk about JavaScript
JavaScript is becoming a platform
X compiles to JavaScript, X = almost anything
Trend: asm.js, WebAssembly... not designed to be written by human
Full-Stack Go
Why
Learn once, Write everywhere
Better tooling compares to JavaScript: gofmt, gooracle, gorename...
Easy concurrency: channels and goroutines instead of callback.
GopherJS
compiles Go into JavaScript
sourcemap
compatibility is really good. support channels and goroutines
can compile itself!
GopherJS Playground (http://gopherjs.github.io/playground/)
Example: https://github.com/shurcooL/Go-Package-Store (https://github.com/shurcooL/Go-Package-Store)
Goroutine
JavaScript is Single-threaded
GopherJS provides a goroutine scheduler
Examples
Hello World
with stdlibs you already know
import "fmt"
func main() { fmt.Println("hello world")}
Export Function
func main() { js.Global.Set("pet", map[string]interface{}{ "New": New, })}
type Pet struct { name string}
func New(name string) *js.Object { return js.MakeWrapper(&Pet{name})}
func (p *Pet) Name() string { return p.name}
func (p *Pet) SetName(name string) { p.name = name}
Callback
func main() { js.Global.Call("requestAnimationFrame", raf)}
func raf(t float64) { js.Global.Call("requestAnimationFrame", raf)
dt := (t - last) / 1000 go animate(dt) last = t}
Performance
DEMO
Bindings
DOM: honnef.co/go/js/dom (honnef.co/go/js/dom)
jQuery: github.com/gopherjs/jquery (github.com/gopherjs/jquery)
JS console: honnef.co/go/js/console (honnef.co/go/js/console)
WebGL: github.com/gopherjs/webgl (github.com/gopherjs/webgl)
WebSocket: github.com/gopherjs/websocket (github.com/gopherjs/websocket)
XHR: honnef.co/go/js/xhr (honnef.co/go/js/xhr)
Gotcha
Import Carefully
No dead code elimiation yet
hello world with fmt
// 753kbimport "fmt"
func main () { fmt.Println("hello world")}
hello world with JS API
// 64kbimport "github.com/gopherjs/gopherjs/js"
func main () { js.Global.Get("console").Call("log", "hello world")}
Blocking
Callbacks should never be blocking
// this will produce an errorjs.Global.Get("myButton").Call("addEventListener", "click", func() { someBlockingFunction()})
Wrap it into a goroutine to fix it
// this works!js.Global.Get("myButton").Call("addEventListener", "click", func() { go func() { someBlockingFunction() }()})
Bad Architecture
Good Architecture
OP = Custom Byte Code
Design as whatever you like
{ "op": "move", "target": "player", "params": { "x": 100, "y": 100}}
<xml><enterprise><op>move</op><target>player</target></enterprise></xml>
Text-based protocol: Cross-platform, Easy to debug, Easy to parse
Different Render Target
Same OP, VM translate it into different API
Different Platform
Same OP, VM implemented in different language
The Go part never changes
Recap
Recap
Write your core logic in Go: Cross-platform, even in browser
Provide text-based protocol for "Write once, run anywhere"
