fixes adding additional quotes to string variables, closes #149

Author: sdiakovskyi-gd

src/main/java/com/mailjet/client/helpers/StringMapSerializer.java

@@ -15,13 +15,13 @@
 public class StringMapSerializer implements JsonSerializer<Map> {
     @Override
     public JsonElement serialize(Map map, Type type, JsonSerializationContext jsonSerializationContext) {
-        Map<String, String> stringMap = new HashMap<>(map.size());
+        Map<String, JsonElement> stringMap = new HashMap<>(map.size());
 
         for (Object entry: map.entrySet()) {
             Map.Entry<String, Object> objectEntry = (Map.Entry<String, Object>) entry;
 
             String key = objectEntry.getKey();
-            String value = jsonSerializationContext.serialize(objectEntry.getValue()).toString();
+            JsonElement value = jsonSerializationContext.serialize(objectEntry.getValue());
 
             stringMap.put(key, value);
         }

src/test/java/com/mailjet/client/TransactionalEmailBuilderTest.java

@@ -0,0 +1,88 @@
+package com.mailjet.client;
+
+import com.mailjet.client.errors.MailjetException;
+import com.mailjet.client.resource.*;
+import com.mailjet.client.resource.sms.SmsSend;
+import com.mailjet.client.transactional.*;
+import com.mailjet.client.transactional.response.SendEmailsResponse;
+import okhttp3.mockwebserver.MockResponse;
+import okhttp3.mockwebserver.MockWebServer;
+import okhttp3.mockwebserver.RecordedRequest;
+import org.json.JSONArray;
+import org.json.JSONObject;
+import org.junit.AfterClass;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import java.io.IOException;
+import java.util.HashMap;
+import java.util.Map;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+public class TransactionalEmailBuilderTest {
+
+    private static MailjetClient client;
+    private static MockWebServer mockWebServer;
+
+    @BeforeClass
+    public static void initialize() throws IOException {
+        mockWebServer = new MockWebServer();
+        mockWebServer.start();
+
+        final ClientOptions clientOptions = ClientOptions
+                .builder()
+                .baseUrl(mockWebServer.url("/").toString())
+                .apiSecretKey("secret-key")
+                .apiKey("api-key")
+                .bearerAccessToken("bearer-token")
+                .build();
+
+        client = new MailjetClient(clientOptions);
+    }
+
+    @Test
+    public void transactionalEmail_WithVariables_ShouldCorrectlyPassVariables() throws MailjetException, InterruptedException {
+
+        // arrange
+        String expectedBody = "{\"Messages\":[{\"Cc\":[],\"TrackClicks\":\"enabled\",\"Bcc\":[],\"Priority\":3,\"Headers\":{},\"From\":{\"Email\":\"xxxxxxxx@xxxxxxx.com\",\"Name\":\"xxxxxxxx xxxxxxxxxx\"},\"Attachments\":[],\"TemplateLanguage\":true,\"TrackOpens\":\"enabled\",\"Variables\":{\"E_DATE\":\"a string text\",\"E_YEAR\":\"another text\",\"E_MAIL_ID\":\"a last text example\"},\"CustomID\":\"8c0725fa-403c-496e-ac7e-xxxxxxxxx\",\"InlinedAttachments\":[],\"To\":[{\"Email\":\"xxxxxxxx@xxxxxxx.com\",\"Name\":\"xxxxxxxx xxxxxxxxxx\"}],\"TemplateID\":1234567}]}";
+
+        mockWebServer.enqueue(new MockResponse().setResponseCode(201).setBody("{}"));
+
+        Map<String, String> variables = new HashMap<>();
+        variables.put("E_DATE", "a string text");
+        variables.put("E_YEAR", "another text");
+        variables.put("E_MAIL_ID", "a last text example");
+
+        TransactionalEmail message = TransactionalEmail
+                .builder()
+                .to(new SendContact("xxxxxxxx@xxxxxxx.com", "xxxxxxxx xxxxxxxxxx"))
+                .from(new SendContact("xxxxxxxx@xxxxxxx.com", "xxxxxxxx xxxxxxxxxx"))
+                .templateID(1234567L)
+                .templateLanguage(true)
+                .priority(3)
+                .customID("8c0725fa-403c-496e-ac7e-xxxxxxxxx")
+                .variables(variables)
+                .trackOpens(TrackOpens.ENABLED)
+                .trackClicks(TrackClicks.ENABLED)
+                .build();
+
+        SendEmailsRequest request = SendEmailsRequest.builder()
+                .message(message)
+                .build();
+
+        // act
+        SendEmailsResponse response = request.sendWith(client);
+
+        // assert
+        RecordedRequest recordedRequest = mockWebServer.takeRequest();
+
+        assertEquals(expectedBody, recordedRequest.getBody().readUtf8());
+    }
+
+    @AfterClass
+    public static void tearDown() throws IOException {
+        mockWebServer.shutdown();
+    }
+}