MDEV-11439 No data type JSON, but CAST(something AS JSON) pretends to

work.

        json_detailed() fixed

mysql-test/r/func_json.result

@@ -567,3 +567,25 @@ json_merge('{"a":{"u":12, "x":"b"}}', '{"a":{"x":"c"}}')
 select json_merge('{"a":{"u":12, "x":"b", "r":1}}', '{"a":{"x":"c", "r":2}}') ;
 json_merge('{"a":{"u":12, "x":"b", "r":1}}', '{"a":{"x":"c", "r":2}}')
 {"a": {"u": 12, "x": ["b", "c"], "r": [1, 2]}}
+select json_compact('{"a":1, "b":[1,2,3], "c":{"aa":"v1", "bb": "v2"}}');
+json_compact('{"a":1, "b":[1,2,3], "c":{"aa":"v1", "bb": "v2"}}')
+{"a":1,"b":[1,2,3],"c":{"aa":"v1","bb":"v2"}}
+select json_loose('{"a":1, "b":[1,2,3], "c":{"aa":"v1", "bb": "v2"}}');
+json_loose('{"a":1, "b":[1,2,3], "c":{"aa":"v1", "bb": "v2"}}')
+{"a": 1, "b": [1, 2, 3], "c": {"aa": "v1", "bb": "v2"}}
+select json_detailed('{"a":1, "b":[1,2,3], "c":{"aa":"v1", "bb": "v2"}}');
+json_detailed('{"a":1, "b":[1,2,3], "c":{"aa":"v1", "bb": "v2"}}')
+{
+    "a": 1,
+    "b": 
+    [
+        1,
+        2,
+        3
+    ],
+    "c": 
+    {
+        "aa": "v1",
+        "bb": "v2"
+    }
+}

mysql-test/t/func_json.test

@@ -234,3 +234,7 @@ select json_merge('{"a":"b"}', '{"a":"c"}') ;
 select json_merge('{"a":{"x":"b"}}', '{"a":"c"}') ;
 select json_merge('{"a":{"u":12, "x":"b"}}', '{"a":{"x":"c"}}') ;
 select json_merge('{"a":{"u":12, "x":"b", "r":1}}', '{"a":{"x":"c", "r":2}}') ;
+
+select json_compact('{"a":1, "b":[1,2,3], "c":{"aa":"v1", "bb": "v2"}}');
+select json_loose('{"a":1, "b":[1,2,3], "c":{"aa":"v1", "bb": "v2"}}');
+select json_detailed('{"a":1, "b":[1,2,3], "c":{"aa":"v1", "bb": "v2"}}');

sql/item_create.cc

@@ -1788,10 +1788,10 @@ protected:
 };
 
 
-class Create_func_json_detailed : public Create_func_arg2
+class Create_func_json_detailed: public Create_native_func
 {
 public:
-  virtual Item *create_2_arg(THD *thd, Item *arg1, Item *arg2);
+  virtual Item *create_native(THD *thd, LEX_STRING name, List<Item> *item_list);
 
   static Create_func_json_detailed s_singleton;
 
@@ -1801,7 +1801,6 @@ protected:
 };
 
 
-
 class Create_func_json_type : public Create_func_arg1
 {
 public:
@@ -5046,9 +5045,25 @@ Create_func_json_exists::create_2_arg(THD *thd, Item *arg1, Item *arg2)
 Create_func_json_detailed Create_func_json_detailed::s_singleton;
 
 Item*
-Create_func_json_detailed::create_2_arg(THD *thd, Item *arg1, Item *arg2)
+Create_func_json_detailed::create_native(THD *thd, LEX_STRING name,
+                                     List<Item> *item_list)
 {
-  return new (thd->mem_root) Item_func_json_format(thd, arg1, arg2);
+  Item *func= NULL;
+  int arg_count= 0;
+
+  if (item_list != NULL)
+    arg_count= item_list->elements;
+
+  if (arg_count < 1 || arg_count > 2 /* json_doc, [path]...*/)
+  {
+    my_error(ER_WRONG_PARAMCOUNT_TO_NATIVE_FCT, MYF(0), name.str);
+  }
+  else
+  {
+    func= new (thd->mem_root) Item_func_json_format(thd, *item_list);
+  }
+
+  return func;
 }
 
 

sql/item_jsonfunc.cc

@@ -113,8 +113,24 @@ static int st_append_escaped(String *s, const String *a)
 }
 
 
+static const int TAB_SIZE_LIMIT= 8;
+static const char tab_arr[TAB_SIZE_LIMIT+1]= "        ";
+
+static int append_tab(String *js, int depth, int tab_size)
+{
+  if (js->append("\n", 1))
+    return 1;
+  for (int i=0; i<depth; i++)
+  {
+    if (js->append(tab_arr, tab_size))
+      return 1;
+  }
+  return 0;
+}
+
+
 static int json_nice(json_engine_t *je, String *nice_js,
-                     Item_func_json_format::formats mode)
+                     Item_func_json_format::formats mode, int tab_size=4)
 {
   int depth= 0;
   const char *comma, *colon;
@@ -122,19 +138,24 @@ static int json_nice(json_engine_t *je, String *nice_js,
   int first_value= 1;
 
   DBUG_ASSERT(je->s.cs == nice_js->charset());
+  DBUG_ASSERT(mode != Item_func_json_format::DETAILED ||
+              (tab_size >= 0 && tab_size <= TAB_SIZE_LIMIT));
 
+  comma= ", ";
+  colon= "\": ";
   if (mode == Item_func_json_format::LOOSE)
   {
-    comma= ", ";
     comma_len= 2;
-    colon= "\": ";
+    colon_len= 3;
+  }
+  else if (mode == Item_func_json_format::DETAILED)
+  {
+    comma_len= 1;
     colon_len= 3;
   }
   else
   {
-    comma= ",";
     comma_len= 1;
-    colon= "\":";
     colon_len= 2;
   }
 
@@ -158,6 +179,10 @@ static int json_nice(json_engine_t *je, String *nice_js,
         if (!first_value)
           nice_js->append(comma, comma_len);
 
+        if (mode == Item_func_json_format::DETAILED &&
+            append_tab(nice_js, depth, tab_size))
+          goto error;
+
         nice_js->append("\"", 1);
         append_simple(nice_js, key_start, key_end - key_start);
         nice_js->append(colon, colon_len);
@@ -170,6 +195,11 @@ static int json_nice(json_engine_t *je, String *nice_js,
       if (!first_value)
         nice_js->append(comma, comma_len);
 
+      if (mode == Item_func_json_format::DETAILED &&
+          depth > 0 &&
+          append_tab(nice_js, depth, tab_size))
+        goto error;
+
 handle_value:
       if (json_read_value(je))
         goto error;
@@ -183,6 +213,10 @@ handle_value:
       }
       else
       {
+        if (mode == Item_func_json_format::DETAILED &&
+            depth > 0 &&
+            append_tab(nice_js, depth, tab_size))
+          goto error;
         nice_js->append((je->value_type == JSON_VALUE_OBJECT) ? "{" : "[", 1);
         first_value= 1;
         depth++;
@@ -193,6 +227,9 @@ handle_value:
     case JST_OBJ_END:
     case JST_ARRAY_END:
       depth--;
+      if (mode == Item_func_json_format::DETAILED &&
+          append_tab(nice_js, depth, tab_size))
+        goto error;
       nice_js->append((je->state == JST_OBJ_END) ? "}": "]", 1);
       first_value= 0;
       break;
@@ -2941,15 +2978,35 @@ String *Item_func_json_format::val_str(String *str)
 {
   String *js= args[0]->val_str(&tmp_js);
   json_engine_t je;
+  int tab_size;
+
   if ((null_value= args[0]->null_value))
     return 0;
 
+  if (fmt == DETAILED)
+  {
+    tab_size= 4;
+    if (arg_count > 1)
+    {
+      tab_size= args[1]->val_int();
+      if (args[1]->null_value)
+      {
+        null_value= 1;
+        return 0;
+      }
+    }
+    if (tab_size < 0)
+      tab_size= 0;
+    else if (tab_size > TAB_SIZE_LIMIT)
+      tab_size= TAB_SIZE_LIMIT;
+  }
+
   json_scan_start(&je, js->charset(), (const uchar *) js->ptr(),
                   (const uchar *) js->ptr()+js->length());
 
   str->length(0);
   str->set_charset(js->charset());
-  if (json_nice(&je, str, fmt))
+  if (json_nice(&je, str, fmt, tab_size))
   {
     null_value= 1;
     report_json_error(js, &je, 0);

sql/item_jsonfunc.h

@@ -443,8 +443,9 @@ protected:
 public:
   Item_func_json_format(THD *thd, Item *js, formats format):
     Item_str_func(thd, js), fmt(format) {}
-  Item_func_json_format(THD *thd, Item *js, Item *tabsize):
-    Item_str_func(thd, js, tabsize), fmt(DETAILED) {}
+  Item_func_json_format(THD *thd, List<Item> &list):
+    Item_str_func(thd, list), fmt(DETAILED) {}
+
   const char *func_name() const;
   void fix_length_and_dec();
   String *val_str(String *str);