reducing scope to package-private, fixing corner case and generalizing truncate method

Author: dhaval24

CHANGELOG.md

@@ -1,9 +1,10 @@
 # CHANGELOG
 
 ## Version 1.0.10
-- Fix issue of sending custom event.
+- Fixed Exceeded property length leads to lost event.
+- Fixed issue of sending custom event.
 - Method `sanitizeStringForJSON` takes string input and converts it to JSON friendly string.
-- Class `com.microsoft.applicationinsights.common.SanitizationUtils` has methods to sanitize string for JSON.
+- Class `com.microsoft.applicationinsights.telemetry.SanitizationUtils` has methods to sanitize string for JSON.
 - Fixed Request Telemetry Sending bug with new schema.
 - Fixed reliability issue with Jedis client dependency collector
 - Fixed Request Telemetry Sending bug with new schema

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

@@ -21,18 +21,16 @@
 
 package com.microsoft.applicationinsights.telemetry;
 
+import com.google.common.base.Strings;
+import com.microsoft.applicationinsights.internal.schemav2.DataPointType;
+import com.microsoft.applicationinsights.internal.util.LocalStringsUtils;
+
 import java.io.BufferedWriter;
 import java.io.IOException;
 import java.io.StringWriter;
 import java.io.Writer;
 import java.util.*;
 
-import com.google.common.base.Strings;
-
-import com.microsoft.applicationinsights.common.SanitizationUtils;
-import com.microsoft.applicationinsights.internal.schemav2.*;
-import com.microsoft.applicationinsights.internal.util.LocalStringsUtils;
-
 /**
  * This class knows how to transform data that is relevant to {@link Telemetry} instances into JSON.
  */
@@ -274,9 +272,10 @@ private <T> void write(T item) throws IOException {
             {
                 out.write(String.valueOf(item));
             } else {
-                String sanitizedItem = SanitizationUtils.sanitizeStringForJSON(String.valueOf(item));
+                String truncatedName = truncate(String.valueOf(item), 8192);
+                String sanitizedItem = SanitizationUtils.sanitizeStringForJSON(truncatedName, false);
                 out.write(JSON_COMMA);
-                out.write(truncateValueToMaxLength(sanitizedItem));
+                out.write(sanitizedItem);
                 out.write(JSON_COMMA);
             }
         }
@@ -297,10 +296,11 @@ private <T extends JsonSerializable> String createJsonFor(T value) throws IOExce
     }
 
     private void writeName(String name) throws IOException {
-        String sanitizedName = SanitizationUtils.sanitizeStringForJSON(name);
+        String truncatedString = truncate(name, 150);
+        String sanitizedName = SanitizationUtils.sanitizeStringForJSON(truncatedString, true);
         out.write(separator);
         out.write(JSON_COMMA);
-        out.write(truncateKeyToMaxLength(sanitizedName));
+        out.write(sanitizedName);
         out.write(JSON_COMMA);
         out.write(JSON_NAME_VALUE_SEPARATOR);
     }
@@ -351,17 +351,11 @@ protected void writeEscapedString(String value) throws IOException {
         }
     }
 
-    private String truncateValueToMaxLength(String value) {
-        if (value.length() > 8192) {
-            return value.substring(0, 8192);
+    private String truncate(String value, int len) {
+        if (value.length() > len) {
+            return value.substring(0, len);
         }
         return value;
     }
 
-    private String truncateKeyToMaxLength(String key) {
-        if (key.length() > 150) {
-            return key.substring(0, 150);
-        }
-        return key;
-    }
 }

core/src/main/java/com/microsoft/applicationinsights/common/SanitizationUtils.java renamed to core/src/main/java/com/microsoft/applicationinsights/telemetry/SanitizationUtils.java

@@ -1,4 +1,4 @@
-package com.microsoft.applicationinsights.common;
+package com.microsoft.applicationinsights.telemetry;
 
 import java.text.StringCharacterIterator;
 
@@ -8,19 +8,22 @@
  * This class provides utility functions to sanitize strings
  * for various formats. Currently it supports JSON sanitization
  */
-public final class SanitizationUtils {
+ final class SanitizationUtils {
 
     /**
      * This method appends escape characters to input String to prevent
      * JSON Sanitization failure
      * @param text
      * @return Sanitized String suitable for JSON
      */
-    public static String sanitizeStringForJSON(String text) {
+     static String sanitizeStringForJSON(String text, boolean isKey) {
 
         final StringBuilder result = new StringBuilder();
         StringCharacterIterator iterator = new StringCharacterIterator(text);
-        for (char curr = iterator.current(); curr != iterator.DONE; curr = iterator.next()) {
+
+        // allowing delta for the characters to be appended
+        int maxAllowedLength = isKey ? 148 : 8190;
+        for (char curr = iterator.current(); curr != iterator.DONE && result.length() < maxAllowedLength; curr = iterator.next()) {
             if( curr == '\"' ){
                 result.append("\\\"");
             }
@@ -52,8 +55,13 @@ else if (!Character.isISOControl(curr)){
                 result.append(curr);
             }
             else {
-                result.append("\\u");
-                result.append((String.format( "%04x", Integer.valueOf(curr))));
+                if (result.length() + 7 < 8192) { // needs 7 more character space to be appended
+                    result.append("\\u");
+                    result.append((String.format( "%04x", Integer.valueOf(curr))));
+                }
+                else {
+                    break;
+                }
             }
         }
         return result.toString();

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

@@ -0,0 +1,18 @@
+package com.microsoft.applicationinsights.telemetry;
+
+import com.microsoft.applicationinsights.telemetry.SanitizationUtils;
+import org.junit.Assert;
+import org.junit.Test;
+
+public class SanitizationUtilsTests {
+
+    @Test
+    public void testSanitizeStringForJSON() {
+
+        String result1 = SanitizationUtils.sanitizeStringForJSON("\\'\\f\\b\\f\\n\\r\\t/\\", false);
+        Assert.assertEquals(result1, "\\\\\\'\\\\f\\\\b\\\\f\\\\n\\\\r\\\\t\\/\\\\");
+
+        String resultControlCharVer = SanitizationUtils.sanitizeStringForJSON("\u0000", true);
+        Assert.assertEquals(resultControlCharVer, "\\u0000");
+    }
+}