feat: Implement Promise.await()

2021-03-23 00:45:02 +07:00
4 changed files with 52 additions and 5 deletions
--- a/example/basic/dist/index.html
+++ b/example/basic/dist/index.html
@ -3,7 +3,7 @@

 <head>
    <meta charset="utf-8" />
-    <title>Golang-WASM</title>
+    <title>Example</title>
 </head>

 <body>
--- a/example/basic/src/api/main.go
+++ b/example/basic/src/api/main.go
@ -13,8 +13,19 @@ func main() {
 	<-c
 }

+const hello = "Sample value"
+
+func helloName(_ js.Value, args []js.Value) interface{} {
+	return fmt.Sprintf("Hello, %s!", args[0].String())
+}
+
 func setup() {
-	fmt.Println("golang-wasm initialized")
+	bridge := js.Global().Get("__go_wasm__")
+
+	bridge.Set("__ready__", true)
+
+	bridge.Set("hello", hello)
+	bridge.Set("helloName", js.FuncOf(helloName))

 	js.Global()
 }
--- a/package.json
+++ b/package.json
@ -1,11 +1,11 @@
 {
-  "name": "golang-wasm",
-  "version": "0.0.1",
+  "name": "go-mod-wasm",
+  "version": "0.1.0",
  "description": "A webpack-based configuration to work with wasm using Go.",
  "main": "src/index.js",
  "repository": {
    "type": "git",
-    "url": "https://gitea.teamortix.com/Team-Ortix/golang-wasm"
+    "url": "https://gitea.teamortix.com/Team-Ortix/go-mod-wasm"
  },
  "keywords": [
    "golang",
--- a/wasm/promise.go
+++ b/wasm/promise.go
@ -15,6 +15,42 @@ func (p *Promise) FromJSValue(value js.Value) error {
 	return err
 }

+// Await waits for the promise to be fulfilled or rejected.
+// It returns an error if there was an error unmarshalling or interacting with JS.
+//
+// This function returns true and sets the value of 'out' if the promise is fulfilled.
+// It returns false and sets the value of 'rej' if the promise is rejected.
+func (p Promise) Await(out, rej interface{}) (bool, error) {
+	resultChan := make(chan js.Value)
+	errChan := make(chan js.Value)
+
+	next, err := p.Get("next")
+	if err != nil {
+		return false, err
+	}
+
+	catch, err := p.Get("catch")
+	if err != nil {
+		return false, err
+	}
+
+	next.Invoke(ToJSValue(func(_, result js.Value) js.Value {
+		resultChan <- result
+		return result
+	}))
+	catch.Invoke(ToJSValue(func(_, err js.Value) js.Value {
+		errChan <- err
+		return err
+	}))
+
+	select {
+	case jsOut := <-resultChan:
+		return true, FromJSValue(jsOut, out)
+	case jsErr := <-errChan:
+		return false, FromJSValue(jsErr, rej)
+	}
+}
+
 // NewPromise returns a promise that is fulfilled or rejected when the provided handler returns.
 // The handler is spawned in its own goroutine.
 func NewPromise(handler func() (interface{}, error)) Promise {