Play with compiling existing Go packages using GopherJS and serving a…

…rchive objects over http with CORS.

Related to gopherjs/gopherjs.github.io#26.

119/main.go

@@ -0,0 +1,42 @@
+// Play with compiling existing Go packages using GopherJS and serving archive objects over http with CORS.
+package main
+
+import (
+	"fmt"
+	"net/http"
+
+	gbuild "github.com/gopherjs/gopherjs/build"
+	"github.com/gopherjs/gopherjs/compiler"
+)
+
+const prefix = "/pkg/"
+
+func main() {
+	http.HandleFunc(prefix, handler)
+	panic(http.ListenAndServe("localhost:8081", nil))
+}
+
+func handler(w http.ResponseWriter, req *http.Request) {
+	pkgPath := req.URL.Path[len(prefix) : len(req.URL.Path)-len(".a.js")]
+
+	w.Header().Set("Access-Control-Allow-Origin", "*")
+	w.Header().Set("Content-Type", "application/octet-stream")
+
+	err := func() error {
+		options := &gbuild.Options{CreateMapFile: false, Verbose: true}
+		s := gbuild.NewSession(options)
+
+		if _, err := s.ImportPackage(pkgPath); err != nil {
+			return err
+		}
+		pkg := s.Packages[pkgPath]
+		if err := compiler.WriteArchive(pkg.Archive, w); err != nil {
+			return err
+		}
+		return nil
+	}()
+	fmt.Println(err)
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusNotFound)
+	}
+}