kite: add request ID to server-side kite handlers

Author: rjeczalik

errors.go

@@ -13,25 +13,32 @@ var ErrKeyNotTrusted = errors.New("kontrol key is not trusted")
 
 // Error is the type of the kite related errors returned from kite package.
 type Error struct {
-	Type    string `json:"type"`
-	Message string `json:"message"`
-	CodeVal string `json:"code"`
+	Type      string `json:"type"`
+	Message   string `json:"message"`
+	CodeVal   string `json:"code"`
+	RequestID string `json:"id"`
 }
 
 func (e Error) Code() string {
 	return e.CodeVal
 }
 
 func (e Error) Error() string {
-	if e.Type == "genericError" || e.Type == "" {
-		return e.Message
+	s := e.Message
+
+	if e.Type != "genericError" && e.Type != "" {
+		s = e.Type + ": " + e.Message
+	}
+
+	if e.RequestID != "" {
+		return s + " (" + e.RequestID + ")"
 	}
 
-	return fmt.Sprintf("%s: %s", e.Type, e.Message)
+	return s
 }
 
 // createError creates a new kite.Error for the given r variable
-func createError(r interface{}) *Error {
+func createError(req *Request, r interface{}) *Error {
 	if r == nil {
 		return nil
 	}
@@ -52,5 +59,9 @@ func createError(r interface{}) *Error {
 		}
 	}
 
+	if kiteErr.RequestID == "" && req != nil {
+		kiteErr.RequestID = req.ID
+	}
+
 	return kiteErr
 }

method_test.go

@@ -2,6 +2,7 @@ package kite
 
 import (
 	"errors"
+	"strings"
 	"testing"
 	"time"
 )
@@ -160,7 +161,7 @@ func TestMethod_Error(t *testing.T) {
 		t.Fatal("PreHandle returns an error, however error is non-nil.")
 	}
 
-	if err.Error() != testError.Error() {
+	if !strings.HasPrefix(err.Error(), testError.Error()) {
 		t.Errorf("Error should be '%v', got '%v'", testError, err)
 	}
 }

request.go

@@ -66,7 +66,7 @@ func (c *Client) runMethod(method *Method, args *dnode.Partial) {
 	defer func() {
 		if r := recover(); r != nil {
 			debug.PrintStack()
-			kiteErr := createError(r)
+			kiteErr := createError(request, r)
 			c.LocalKite.Log.Error(kiteErr.Error()) // let's log it too :)
 			callFunc(nil, kiteErr)
 		}
@@ -76,7 +76,7 @@ func (c *Client) runMethod(method *Method, args *dnode.Partial) {
 	request, callFunc = c.newRequest(method.name, args)
 	if method.authenticate {
 		if err := request.authenticate(); err != nil {
-			callFunc(nil, err)
+			callFunc(nil, createError(request, err))
 			return
 		}
 	} else {
@@ -101,16 +101,17 @@ func (c *Client) runMethod(method *Method, args *dnode.Partial) {
 	// available more so it will return a zero.
 	if method.bucket != nil && method.bucket.TakeAvailable(1) == 0 {
 		callFunc(nil, &Error{
-			Type:    "requestLimitError",
-			Message: "The maximum request rate is exceeded.",
+			Type:      "requestLimitError",
+			Message:   "The maximum request rate is exceeded.",
+			RequestID: request.ID,
 		})
 		return
 	}
 
 	// Call the handler functions.
 	result, err := method.ServeKite(request)
 
-	callFunc(result, createError(err))
+	callFunc(result, createError(request, err))
 }
 
 // runCallback is called when a callback method call is received from remote Kite.