Update callback calling place

- Callback for every result, even it contains error
- User can handle it using Result.Err

examples/example.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"fmt"
 	"log"
 
 	"github.com/projectdiscovery/goflags"
@@ -14,8 +15,16 @@ func main() {
 
 	options := runner.Options{
 		Methods:         "GET",
-		InputTargetHost: goflags.StringSlice{"scanme.sh", "projectdiscovery.io"},
+		InputTargetHost: goflags.StringSlice{"scanme.sh", "projectdiscovery.io", "localhost"},
 		//InputFile: "./targetDomains.txt", // path to file containing the target domains list
+		OnResult: func(r runner.Result) {
+			// handle error
+			if r.Err != nil {
+				fmt.Printf("[Err] %s: %s\n", r.Input, r.Err)
+				return
+			}
+			fmt.Printf("%s %s %d\n", r.Input, r.Host, r.StatusCode)
+		},
 	}
 
 	if err := options.ValidateOptions(); err != nil {

runner/options.go

@@ -262,6 +262,7 @@ type Options struct {
 	ListDSLVariable           bool
 	OutputFilterCondition     string
 	OutputMatchCondition      string
+	//The OnResult callback function is invoked for each result. It is important to check for errors in the result before using Result.Err.
 	OnResult           OnResultCallback
 	DisableUpdateCheck bool
 	NoDecode           bool

runner/runner.go

@@ -663,6 +663,13 @@ func (r *Runner) RunEnumeration() {
 		}
 
 		for resp := range output {
+
+			// call the callback function if any
+			// be careful and check for result.Err
+			if r.options.OnResult != nil {
+				r.options.OnResult(resp)
+			}
+
 			if resp.Err != nil {
 				// Change the error message if any port value passed explicitly
 				if url, err := r.parseURL(resp.URL); err == nil && url.Port() != "" {