sandbox improvements

- remove needless string/bytes conversion - remove Code member

Author: usrbinsam

docker/main.go

@@ -13,7 +13,6 @@ import (
 "os/exec"
 "path"
 "strconv"
-"strings"
 "time"
 )
 
@@ -23,15 +22,14 @@ type Response struct {
 Output string `json:"output"`
 Error string `json:"error"`
 ExecutionTime int64 `json:"time"`
-Code string `json:"code"`
 }
 
 func (r Response) toJSON() string {
 data, _ := json.Marshal(r)
 return string(data)
 }
 
-func execSandbox(interpreter string, timeout time.Duration, code *string) *Response {
+func execSandbox(interpreter string, timeout time.Duration, code []byte) *Response {
 res := Response{}
 ApplySyscallRestrictions()
 
@@ -40,8 +38,7 @@ func execSandbox(interpreter string, timeout time.Duration, code *string) *Respo
 defer cancel()
 
 cmd := exec.CommandContext(ctx, interpreter)
-cmd.Stdin = strings.NewReader(*code)
-res.Code = *code
+cmd.Stdin = bytes.NewReader(code)
 
 var errBuffer bytes.Buffer
 cmd.Stderr = &errBuffer
@@ -95,15 +92,15 @@ func main() {
 
 debug("reading file: %s", filename)
 code, err := ioutil.ReadFile(filename)
-data := string(code)
+// data := string(code)
 
 if err != nil {
 panic(err.Error())
 }
 
 var (
 interpreter string
-response Response
+response *Response
 )
 
 switch language {
@@ -115,12 +112,12 @@ func main() {
 case "node":
 interpreter = "node"
 default:
-response.Error = fmt.Sprintf("unrecognized language %q", language)
+response = &Response{Error: "unrecognized language: " + language}
 fmt.Print(response.toJSON())
 return
 }
 
-response = *execSandbox(interpreter, duration, &data)
+response = execSandbox(interpreter, duration, code)
 
 fmt.Print(response.toJSON())
 }