8 files changed, 128 insertions, 6 deletions
diff --git a/src/main/java/org/luxons/sevenwonders/controllers/LobbyController.java b/src/main/java/org/luxons/sevenwonders/controllers/LobbyController.java
index 7567c330..e15935d6 100644
--- a/src/main/java/org/luxons/sevenwonders/controllers/LobbyController.java
+++ b/src/main/java/org/luxons/sevenwonders/controllers/LobbyController.java
@@ -7,6 +7,8 @@ import java.util.Map;
 
 import org.luxons.sevenwonders.actions.JoinOrCreateGameAction;
 import org.luxons.sevenwonders.actions.StartGameAction;
+import org.luxons.sevenwonders.errors.ErrorFactory;
+import org.luxons.sevenwonders.errors.UIError;
 import org.luxons.sevenwonders.errors.UniqueIdAlreadyUsedException;
 import org.luxons.sevenwonders.game.Game;
 import org.luxons.sevenwonders.game.Lobby;
@@ -36,6 +38,8 @@ public class LobbyController {
 
     private final SimpMessagingTemplate template;
 
+    private final ErrorFactory errorFactory;
+
     private long lastGameId = 0;
 
     private Map<String, Lobby> lobbies = new HashMap<>();
@@ -43,16 +47,18 @@ public class LobbyController {
     private Map<String, Game> games = new HashMap<>();
 
     @Autowired
-    public LobbyController(GameDefinitionLoader gameDefinitionLoader, SimpMessagingTemplate template) {
+    public LobbyController(GameDefinitionLoader gameDefinitionLoader, SimpMessagingTemplate template,
+            ErrorFactory errorFactory) {
         this.gameDefinitionLoader = gameDefinitionLoader;
         this.template = template;
+        this.errorFactory = errorFactory;
     }
 
     @MessageExceptionHandler
     @SendToUser("/queue/errors")
-    public String handleException(Throwable exception) {
+    public UIError handleException(Throwable exception) {
         logger.error("An error occured during message handling", exception);
-        return exception.getClass().getSimpleName() + ": " + exception.getMessage();
+        return errorFactory.createError(exception);
     }
 
     @MessageMapping("/create-game")
diff --git a/src/main/java/org/luxons/sevenwonders/errors/ErrorFactory.java b/src/main/java/org/luxons/sevenwonders/errors/ErrorFactory.java
new file mode 100644
index 00000000..2d3dcd0b
--- /dev/null
+++ b/src/main/java/org/luxons/sevenwonders/errors/ErrorFactory.java
@@ -0,0 +1,52 @@
+package org.luxons.sevenwonders.errors;
+
+import java.util.List;
+import java.util.Locale;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.MessageSource;
+import org.springframework.messaging.handler.annotation.support.MethodArgumentNotValidException;
+import org.springframework.stereotype.Component;
+import org.springframework.validation.ObjectError;
+
+@Component
+public class ErrorFactory {
+
+    private static final String ERROR_CODE_VALIDATION = "VALIDATION_ERROR";
+
+    private static final String ERROR_MSG_VALIDATION = "Input invalid";
+
+    private final MessageSource messageSource;
+
+    @Autowired
+    public ErrorFactory(MessageSource messageSource) {
+        this.messageSource = messageSource;
+    }
+
+    public UIError createError(Throwable exception) {
+        if (exception instanceof UserInputException) {
+            return createUserError((UserInputException)exception);
+        } else if (exception instanceof MethodArgumentNotValidException) {
+            return createValidationError((MethodArgumentNotValidException)exception);
+        } else {
+            return createInternalError(exception);
+        }
+    }
+
+    private UIError createUserError(UserInputException exception) {
+        String messageKey = exception.getMessageResourceKey();
+        String message = messageSource.getMessage(messageKey, null, messageKey, Locale.US);
+        return new UIError(messageKey, message, ErrorType.USER);
+    }
+
+    private UIError createInternalError(Throwable exception) {
+        return new UIError(exception.getClass().getSimpleName(), exception.getMessage(), ErrorType.INTERNAL);
+    }
+
+    private UIError createValidationError(MethodArgumentNotValidException exception) {
+        List<ObjectError> errors = exception.getBindingResult().getAllErrors();
+        UIError uiError = new UIError(ERROR_CODE_VALIDATION, ERROR_MSG_VALIDATION, ErrorType.VALIDATION);
+        uiError.setValidationErrors(errors);
+        return uiError;
+    }
+}
diff --git a/src/main/java/org/luxons/sevenwonders/errors/ErrorType.java b/src/main/java/org/luxons/sevenwonders/errors/ErrorType.java
new file mode 100644
index 00000000..71df185f
--- /dev/null
+++ b/src/main/java/org/luxons/sevenwonders/errors/ErrorType.java
@@ -0,0 +1,7 @@
+package org.luxons.sevenwonders.errors;
+
+public enum ErrorType {
+    USER,
+    VALIDATION,
+    INTERNAL
+}
diff --git a/src/main/java/org/luxons/sevenwonders/errors/UIError.java b/src/main/java/org/luxons/sevenwonders/errors/UIError.java
new file mode 100644
index 00000000..67802f22
--- /dev/null
+++ b/src/main/java/org/luxons/sevenwonders/errors/UIError.java
@@ -0,0 +1,42 @@
+package org.luxons.sevenwonders.errors;
+
+import java.util.List;
+
+import org.springframework.validation.ObjectError;
+
+public class UIError {
+
+    private final String code;
+
+    private final String message;
+
+    private final ErrorType type;
+
+    private List<ObjectError> validationErrors;
+
+    public UIError(String code, String message, ErrorType type) {
+        this.code = code;
+        this.message = message;
+        this.type = type;
+    }
+
+    public String getCode() {
+        return code;
+    }
+
+    public String getMessage() {
+        return message;
+    }
+
+    public ErrorType getType() {
+        return type;
+    }
+
+    public List<ObjectError> getValidationErrors() {
+        return validationErrors;
+    }
+
+    public void setValidationErrors(List<ObjectError> validationErrors) {
+        this.validationErrors = validationErrors;
+    }
+}
diff --git a/src/main/java/org/luxons/sevenwonders/controllers/UniqueIdAlreadyUsedException.java b/src/main/java/org/luxons/sevenwonders/errors/UniqueIdAlreadyUsedException.java
index 56c22655..b1b00453 100644
--- a/src/main/java/org/luxons/sevenwonders/controllers/UniqueIdAlreadyUsedException.java
+++ b/src/main/java/org/luxons/sevenwonders/errors/UniqueIdAlreadyUsedException.java
@@ -1,4 +1,4 @@
-package org.luxons.sevenwonders.controllers;
+package org.luxons.sevenwonders.errors;
 
 public class UniqueIdAlreadyUsedException extends RuntimeException {
 
diff --git a/src/main/java/org/luxons/sevenwonders/errors/UserInputException.java b/src/main/java/org/luxons/sevenwonders/errors/UserInputException.java
new file mode 100644
index 00000000..11f7f8f2
--- /dev/null
+++ b/src/main/java/org/luxons/sevenwonders/errors/UserInputException.java
@@ -0,0 +1,14 @@
+package org.luxons.sevenwonders.errors;
+
+public class UserInputException extends RuntimeException {
+
+    private final String messageResourceKey;
+
+    public UserInputException(String messageResourceKey) {
+        this.messageResourceKey = messageResourceKey;
+    }
+
+    public String getMessageResourceKey() {
+        return messageResourceKey;
+    }
+}
diff --git a/src/main/java/org/luxons/sevenwonders/game/Lobby.java b/src/main/java/org/luxons/sevenwonders/game/Lobby.java
index 7fdffef5..16d4e8a3 100644
--- a/src/main/java/org/luxons/sevenwonders/game/Lobby.java
+++ b/src/main/java/org/luxons/sevenwonders/game/Lobby.java
@@ -3,7 +3,7 @@ package org.luxons.sevenwonders.game;
 import java.util.ArrayList;
 import java.util.List;
 
-import org.luxons.sevenwonders.controllers.UniqueIdAlreadyUsedException;
+import org.luxons.sevenwonders.errors.UniqueIdAlreadyUsedException;
 import org.luxons.sevenwonders.game.data.GameDefinition;
 
 public class Lobby {
diff --git a/src/main/resources/static/app.js b/src/main/resources/static/app.js
index b1881357..ace23fdb 100644
--- a/src/main/resources/static/app.js
+++ b/src/main/resources/static/app.js
@@ -19,7 +19,8 @@ function connect() {
     console.log('Connected: ' + frame);
 
     stompClient.subscribe('/user/queue/errors', function (msg) {
-      console.error(msg.body);
+      var error = JSON.parse(msg.body);
+      console.error(error);
     });
 
     stompClient.subscribe('/topic/games', function (msg) {