Adding truncate methods removing unnecessary test as following covers all

Author: dhaval24

core/src/main/java/com/microsoft/applicationinsights/common/SanitizationUtils.java

@@ -48,9 +48,13 @@ else if(curr == '\r'){
             else if(curr == '\t'){
                 result.append("\\t");
             }
-            else {
+            else if (!Character.isISOControl(curr)){
                 result.append(curr);
             }
+            else {
+                result.append("\\u");
+                result.append((String.format( "%04x", Integer.valueOf(curr))));
+            }
         }
         return result.toString();
     }

core/src/main/java/com/microsoft/applicationinsights/telemetry/JsonTelemetryDataSerializer.java

@@ -276,7 +276,7 @@ private <T> void write(T item) throws IOException {
             } else {
                 String sanitizedItem = SanitizationUtils.sanitizeStringForJSON(String.valueOf(item));
                 out.write(JSON_COMMA);
-                out.write(sanitizedItem);
+                out.write(truncateValueToMaxLength(sanitizedItem));
                 out.write(JSON_COMMA);
             }
         }
@@ -297,9 +297,10 @@ private <T extends JsonSerializable> String createJsonFor(T value) throws IOExce
     }
 
     private void writeName(String name) throws IOException {
+        String sanitizedName = SanitizationUtils.sanitizeStringForJSON(name);
         out.write(separator);
         out.write(JSON_COMMA);
-        out.write(name);
+        out.write(truncateKeyToMaxLength(sanitizedName));
         out.write(JSON_COMMA);
         out.write(JSON_NAME_VALUE_SEPARATOR);
     }
@@ -349,4 +350,18 @@ protected void writeEscapedString(String value) throws IOException {
             }
         }
     }
+
+    private String truncateValueToMaxLength(String value) {
+        if (value.length() > 8192) {
+            return value.substring(0, 8192);
+        }
+        return value;
+    }
+
+    private String truncateKeyToMaxLength(String key) {
+        if (key.length() > 150) {
+            return key.substring(0, 150);
+        }
+        return key;
+    }
 }

core/src/test/java/com/microsoft/applicationinsights/common/SanitizationUtilsTests.java

@@ -7,12 +7,11 @@ public class SanitizationUtilsTests {
 
     @Test
     public void testSanitizeStringForJSON() {
-        String result = SanitizationUtils.sanitizeStringForJSON("{\"entityType\":\"CONTACTNAME\",\"contactField\":\"\"," +
-                "\"query\":\"zuck\",\"candidates\":[{\"id\":\"2\",\"name\":\"Andrew Zuck\",\"aliases\":[],\"phoneNumbers\":[{\"type\":\"MOBILENUMBER\",\"number\":\"+1 (555) 222-2222\"}],\"emailAddresses\":[],\"streetAddresses\":[]}],\"scores\":{\"2\":2.327993297520463}}");
-        Assert.assertEquals(result, "{\\\"entityType\\\":\\\"CONTACTNAME\\\",\\\"contactField\\\":\\\"\\\",\\\"query\\\":\\\"zuck\\\",\\\"candidates\\\":[{\\\"id\\\":\\\"2\\\",\\\"name\\\":\\\"Andrew Zuck\\\",\\\"aliases\\\":[],\\\"phoneNumbers\\\":[{\\\"type\\\":\\\"MOBILENUMBER\\\",\\\"number\\\":\\\"+1 (555) 222-2222\\\"}],\\\"emailAddresses\\\"" +
-                ":[],\\\"streetAddresses\\\":[]}],\\\"scores\\\":{\\\"2\\\":2.327993297520463}}");
 
         String resutl1 = SanitizationUtils.sanitizeStringForJSON("\\'\\f\\b\\f\\n\\r\\t/\\");
         Assert.assertEquals(resutl1, "\\\\\\'\\\\f\\\\b\\\\f\\\\n\\\\r\\\\t\\/\\\\");
+
+        String resultControlCharVer = SanitizationUtils.sanitizeStringForJSON("\u0000");
+        Assert.assertEquals(resultControlCharVer, "\\u0000");
     }
 }