op-geth/ethutil/natspec/natspec.go

64 lines
1.7 KiB
Go

package natspec
import (
"fmt"
"github.com/obscuren/otto"
)
type NatSpec struct {
jsvm *otto.Otto
}
// TODO: should initialise with abi and userdoc jsons
func New() (self *NatSpec, err error) {
self = new(NatSpec)
self.jsvm = otto.New()
_, err = self.jsvm.Run(natspecJS)
if err != nil {
return
}
_, err = self.jsvm.Run("var natspec = require('natspec');")
if err != nil {
return
}
return
}
func (self *NatSpec) Notice(transaction, abi, method, expression string) (string, error) {
var err error
if _, err = self.jsvm.Run("var transaction = " + transaction + ";"); err != nil {
return "", fmt.Errorf("natspec.js error setting transaction: %v", err)
}
if _, err = self.jsvm.Run("var abi = " + abi + ";"); err != nil {
return "", fmt.Errorf("natspec.js error setting abi: %v", err)
}
if _, err = self.jsvm.Run("var method = '" + method + "';"); err != nil {
return "", fmt.Errorf("natspec.js error setting method: %v", err)
}
if _, err = self.jsvm.Run("var expression = \"" + expression + "\";"); err != nil {
return "", fmt.Errorf("natspec.js error setting expression: %v", err)
}
self.jsvm.Run("var call = {method: method,abi: abi,transaction: transaction};")
value, err := self.jsvm.Run("natspec.evaluateExpression(expression, call);")
if err != nil {
return "", fmt.Errorf("natspec.js error evaluating expression: %v", err)
}
evalError := "Natspec evaluation failed, wrong input params"
if value.String() == evalError {
return "", fmt.Errorf("natspec.js error evaluating expression: wrong input params in expression '%s'", expression)
}
if len(value.String()) == 0 {
return "", fmt.Errorf("natspec.js error evaluating expression")
}
return value.String(), nil
}