create error map

client_handlers.go

@@ -45,7 +45,7 @@ func SetHttpHandler(w *http.ResponseWriter, req *http.Request) {
 	if len(command.Value) == 0 {
 		(*w).WriteHeader(http.StatusBadRequest)
 
-		(*w).Write(newJsonError("400", "Value is Required"))
+		(*w).Write(newJsonError(200, ""))
 		return
 	}
 
@@ -59,7 +59,7 @@ func SetHttpHandler(w *http.ResponseWriter, req *http.Request) {
 
 		(*w).WriteHeader(http.StatusBadRequest)
 
-		(*w).Write(newJsonError("400", "The given TTL is not a number"))
+		(*w).Write(newJsonError(202, ""))
 	}
 
 	dispatch(command, w, req, true)
@@ -81,7 +81,7 @@ func TestAndSetHttpHandler(w http.ResponseWriter, req *http.Request) {
 	if len(command.Value) == 0 {
 		w.WriteHeader(http.StatusBadRequest)
 
-		w.Write(newJsonError("400", "TestAndSet: Value Required"))
+		w.Write(newJsonError(200, "TestAndSet"))
 
 		return
 	}
@@ -89,7 +89,7 @@ func TestAndSetHttpHandler(w http.ResponseWriter, req *http.Request) {
 	if len(command.PrevValue) == 0 {
 		w.WriteHeader(http.StatusBadRequest)
 
-		w.Write(newJsonError("400", "TestAndSet: PrevValue Required"))
+		w.Write(newJsonError(201, "TestAndSet"))
 		return
 	}
 
@@ -102,7 +102,7 @@ func TestAndSetHttpHandler(w http.ResponseWriter, req *http.Request) {
 	if err != nil {
 		w.WriteHeader(http.StatusBadRequest)
 
-		w.Write(newJsonError("400", "The given TTL is not a number"))
+		w.Write(newJsonError(202, "TestAndSet"))
 	}
 
 	dispatch(command, &w, req, true)
@@ -132,11 +132,11 @@ func dispatch(c Command, w *http.ResponseWriter, req *http.Request, client bool)
 
 			if _, ok := err.(store.TestFail); ok {
 				(*w).WriteHeader(http.StatusBadRequest)
-				(*w).Write(newJsonError("400", err.Error()))
+				(*w).Write(newJsonError(101, err.Error()))
 				return
 			}
 			(*w).WriteHeader(http.StatusInternalServerError)
-			(*w).Write(newJsonError("500", "Internal Error"))
+			(*w).Write(newJsonError(300, ""))
 			return
 		} else {
 
@@ -157,7 +157,7 @@ func dispatch(c Command, w *http.ResponseWriter, req *http.Request, client bool)
 		// current no leader
 		if raftServer.Leader() == "" {
 			(*w).WriteHeader(http.StatusInternalServerError)
-			(*w).Write(newJsonError("500", "During Leader Election Period"))
+			(*w).Write(newJsonError(300, ""))
 			return
 		}
 
@@ -185,7 +185,7 @@ func dispatch(c Command, w *http.ResponseWriter, req *http.Request, client bool)
 		return
 	}
 	(*w).WriteHeader(http.StatusInternalServerError)
-	(*w).Write(newJsonError("500", "Internal Error"))
+	(*w).Write(newJsonError(300, ""))
 	return
 }
 
@@ -219,7 +219,7 @@ func GetHttpHandler(w *http.ResponseWriter, req *http.Request) {
 		}
 
 		(*w).WriteHeader(http.StatusInternalServerError)
-		(*w).Write(newJsonError("500", "Internal Error"))
+		(*w).Write(newJsonError(300, ""))
 		return
 	} else {
 		body, ok := body.([]byte)
@@ -250,7 +250,7 @@ func ListHttpHandler(w http.ResponseWriter, req *http.Request) {
 			return
 		}
 		w.WriteHeader(http.StatusInternalServerError)
-		w.Write(newJsonError("500", "Internal Error"))
+		w.Write(newJsonError(300, ""))
 		return
 	} else {
 		w.WriteHeader(http.StatusOK)
@@ -286,7 +286,7 @@ func WatchHttpHandler(w http.ResponseWriter, req *http.Request) {
 		sinceIndex, err := strconv.ParseUint(string(content), 10, 64)
 		if err != nil {
 			w.WriteHeader(http.StatusBadRequest)
-			w.Write(newJsonError("400", "Watch From Index: Vaild Index Required"))
+			w.Write(newJsonError(203, "Watch From Index"))
 		}
 		command.SinceIndex = sinceIndex
 

error.go

@@ -4,15 +4,34 @@ import (
 	"encoding/json"
 )
 
+var errors map[int]string
+
+func init() {
+	errors = make(map[int]string)
+
+	// command related errors
+	errors[100] = "Key Not Found"
+	errors[101] = "The given PrevValue is not equal to the value of the key"
+	// Post form related errors
+	errors[200] = "Value is Required in POST form"
+	errors[201] = "PrevValue is Required in POST form"
+	errors[202] = "The given TTL in POST form is not a number"
+	errors[203] = "The given index in POST form is not a number"
+	// raft related errors
+	errors[300] = "Raft Internal Error"
+}
+
 type jsonError struct {
-	StatusCode string `json:"statusCode"`
-	Message    string `json:"message"`
+	ErrorCode int    `json:"errorCode"`
+	Message   string `json:"message"`
+	Cause     string `json:"cause,omitempty"`
 }
 
-func newJsonError(statusCode string, message string) []byte {
+func newJsonError(errorCode int, cause string) []byte {
 	b, _ := json.Marshal(jsonError{
-		StatusCode: statusCode,
-		Message:    message,
+		ErrorCode: errorCode,
+		Message:   errors[errorCode],
+		Cause:     cause,
 	})
 	return b
 }

store/error.go

@@ -1,23 +1,19 @@
 package store
 
-import (
-	"fmt"
-	)
-
 type NotFoundError string
 
 func (e NotFoundError) Error() string {
-	return fmt.Sprintf("Key %s Not Found", string(e))
+	return string(e)
 }
 
 type NotFile string
 
 func (e NotFile) Error() string {
-	return fmt.Sprintf("Try to set value to a dir %s", string(e))
+	return string(e)
 }
 
 type TestFail string
 
 func (e TestFail) Error() string {
-	return fmt.Sprintf("Test %s fails", string(e))
+	return string(e)
 }

store/store.go

@@ -376,7 +376,7 @@ func (s *Store) TestAndSet(key string, prevValue string, value string, expireTim
 	} else {
 
 		// If fails, return err
-		err := TestFail(fmt.Sprintf("%s==%s", resp.Value, prevValue))
+		err := TestFail(fmt.Sprintf("TestAndSet: %s!=%s", resp.Value, prevValue))
 		return nil, err
 	}