Merge pull request #18 from pheyken/map-error-code

add errorCode to InvalidMessageException

Author: ibalosh

src/main/java/com/wildbit/java/postmark/client/HttpClientHandler.java

@@ -140,7 +140,7 @@ private void validateResponse(HttpClient.ClientResponse response) throws Postmar
                 throw new InvalidAPIKeyException(dataHandler.formatErrorMessage(message));
 
             case 422:
-                throw new InvalidMessageException(dataHandler.formatErrorMessage(message));
+                throw new InvalidMessageException(dataHandler.formatErrorMessage(message), dataHandler.formatErrorCode(message));
 
             case 500:
                 throw new InternalServerException(dataHandler.formatErrorMessage(message));

src/main/java/com/wildbit/java/postmark/client/data/DataHandler.java

@@ -70,6 +70,23 @@ public String formatErrorMessage(String data) throws IOException {
         return node.get("Message").textValue();
     }
 
+    /**
+     * Helper for filtering out error code returned by Postmark in case of HTTP status code 422
+     * @param data JSON object as String
+     * @return error code
+     * @throws IOException in case converting String to Object fails
+     */
+    public Integer formatErrorCode(String data) throws IOException {
+        JsonNode node = fromJson(data, JsonNode.class);
+        JsonNode errorCodeNode = node.get("ErrorCode");
+
+        if (errorCodeNode == null || errorCodeNode.isNull()) {
+            return null;
+        }
+
+        return errorCodeNode.intValue();
+    }
+
     /**
      * Sets data mapper to be strict when making conversion of data to objects.
      * If there is a mismatch between object and String in any other case than letter case,

src/main/java/com/wildbit/java/postmark/client/exception/InvalidMessageException.java

@@ -5,8 +5,15 @@
  */
 
 public class InvalidMessageException extends PostmarkException {
-    public InvalidMessageException(String message) {
+    private final Integer errorCode;
+
+    public InvalidMessageException(String message, Integer errorCode) {
         super(message);
+        this.errorCode = errorCode;
+    }
+
+    public Integer getErrorCode() {
+        return errorCode;
     }
 }