Allow to export JSON with unescaped unicode chars

This is optional as there are some parsers which have problems with
utf-8, see http://stackoverflow.com/q/4901133/225718

Fixes #12946

Signed-off-by: Michal Čihař <michal@cihar.com>

ChangeLog

@@ -2,6 +2,7 @@ phpMyAdmin - ChangeLog
 ======================
 
 4.8.0 (not yet released)
+- issue #12946 Allow to export JSON with unescaped unicode chars
 
 4.7.0.0 (not yet released)
 - patch #12233 [Display] Improve message when renaming database to same name

export.php

@@ -95,6 +95,7 @@ $post_params = array(
         'ods_columns',
         'json_structure_or_data',
         'json_pretty_print',
+        'json_unicode',
         'xml_structure_or_data',
         'xml_export_events',
         'xml_export_functions',

libraries/config.default.php

@@ -1855,6 +1855,13 @@ $cfg['Export']['json_structure_or_data'] = 'data';
  */
 $cfg['Export']['json_pretty_print'] = false;
 
+/**
+ * Export functions
+ *
+ * @global string $cfg['Export']['json_unicode']
+ */
+$cfg['Export']['json_unicode'] = true;
+
 /**
  *
  *

libraries/plugins/export/ExportJson.php

@@ -43,13 +43,18 @@ class ExportJson extends ExportPlugin
      */
     public function encode($data)
     {
+        $options = 0;
         if (isset($GLOBALS['json_pretty_print'])
             && $GLOBALS['json_pretty_print']
         ) {
-            return json_encode($data, JSON_PRETTY_PRINT);
-        } else {
-            return json_encode($data);
+            $options |= JSON_PRETTY_PRINT;
         }
+        if (isset($GLOBALS['json_unicode'])
+            && $GLOBALS['json_unicode']
+        ) {
+            $options |= JSON_UNESCAPED_UNICODE;
+        }
+        return json_encode($data, $options);
     }
 
     /**
@@ -84,6 +89,12 @@ class ExportJson extends ExportPlugin
         );
         $generalOptions->addProperty($leaf);
 
+        $leaf = new BoolPropertyItem(
+            'unicode',
+            __('Output unicode characters unescaped')
+        );
+        $generalOptions->addProperty($leaf);
+
         // add the main group to the root group
         $exportSpecificOptions->addProperty($generalOptions);