support json type

src/sql/engine/expr/ob_expr_json_quote.cpp

@@ -0,0 +1,169 @@
+/**
+ * Copyright (c) 2021 OceanBase
+ * OceanBase CE is licensed under Mulan PubL v2.
+ * You can use this software according to the terms and conditions of the Mulan PubL v2.
+ * You may obtain a copy of Mulan PubL v2 at:
+ *          http://license.coscl.org.cn/MulanPubL-2.0
+ * THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
+ * EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
+ * MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
+ * See the Mulan PubL v2 for more details.
+ */
+
+// This file is for implementation of func json_quote
+#define USING_LOG_PREFIX SQL_ENG
+#include "ob_expr_json_quote.h"
+#include "sql/engine/expr/ob_expr_json_func_helper.h"
+
+using namespace oceanbase::common;
+using namespace oceanbase::sql;
+
+namespace oceanbase
+{
+namespace sql
+{
+ObExprJsonQuote::ObExprJsonQuote(ObIAllocator &alloc)
+    : ObFuncExprOperator(alloc,
+      T_FUN_SYS_JSON_QUOTE,
+      N_JSON_QUOTE, 
+      1, NOT_ROW_DIMENSION)
+{
+}
+
+ObExprJsonQuote::~ObExprJsonQuote()
+{
+}
+
+int ObExprJsonQuote::calc_result_type1(ObExprResType &type,
+                                       ObExprResType &type1,
+                                       common::ObExprTypeCtx &type_ctx) const
+{
+  UNUSED(type_ctx);
+  INIT_SUCC(ret);
+  type.set_type(ObLongTextType);
+  type.set_collation_type(CS_TYPE_UTF8MB4_BIN);
+  type.set_collation_level(CS_LEVEL_IMPLICIT);
+
+  if (type1.get_type() == ObNullType || type1.get_type() == ObDoubleType
+      || type1.get_type() == ObIntType) {
+    // do nothing
+  } else if (ob_is_string_type(type1.get_type()) && type1.get_collation_type() != CS_TYPE_BINARY) {
+    if (type1.get_charset_type() != CHARSET_UTF8MB4) {
+      type1.set_calc_collation_type(CS_TYPE_UTF8MB4_BIN);
+    }
+  }
+  
+  return ret;
+}
+
+
+template <typename T>
+int ObExprJsonQuote::calc(const T &data, ObObjType type, ObCollationType cs_type, 
+                          ObJsonBuffer &j_buf, bool &is_null)
+{
+  INIT_SUCC(ret);
+
+  if (type == ObIntType || type == ObDoubleType) {
+    // special for mathematical function, consistent with mysql
+    if (data.is_null()) {
+      is_null = true;
+    } else {
+      ret = OB_ERR_INVALID_TYPE_FOR_ARGUMENT;
+      LOG_USER_ERROR(OB_ERR_INVALID_TYPE_FOR_ARGUMENT);
+    }
+  } else if (type == ObNullType || data.is_null()) {
+    is_null = true;
+  } else if (!ob_is_string_type(type)) {
+    LOG_WARN("invalid type", K(type));
+    ret = OB_ERR_INVALID_TYPE_FOR_ARGUMENT;
+    LOG_USER_ERROR(OB_ERR_INVALID_TYPE_FOR_ARGUMENT);
+  } else if (OB_FAIL(ObJsonExprHelper::ensure_collation(type, cs_type))) {
+    LOG_WARN("fail to ensure collation", K(ret), K(type), K(cs_type));
+  } else { // string type
+    ObString json_val = data.get_string();
+    size_t len = json_val.length();
+    if (len == 0) {
+      if (OB_FAIL(j_buf.append("\"\"", 2))) {
+        LOG_WARN("failed: jbuf append", K(ret));        
+      }
+    } else if (OB_FAIL(ObJsonPathUtil::double_quote(json_val, &j_buf))) {
+      LOG_WARN("failed: add double quote", K(ret), K(json_val));
+    }
+  }
+
+  return ret;
+}
+
+// for old sql engine
+int ObExprJsonQuote::calc_result1(common::ObObj &result, const common::ObObj &obj,
+                                  common::ObExprCtx &expr_ctx) const
+{ 
+  INIT_SUCC(ret);
+  ObIAllocator *allocator = expr_ctx.calc_buf_;
+  ObJsonBuffer j_buf(allocator);
+  bool is_null= false;
+
+  if (OB_ISNULL(allocator)) { // check allocator
+    ret = OB_NOT_INIT;
+    LOG_WARN("allcator not init", K(ret));
+  } else if (OB_FAIL(calc(obj, obj.get_type(), obj.get_collation_type(), j_buf, is_null))) {
+    LOG_WARN("fail to calc json quote result in old engine", K(ret), K(obj.get_type()));
+  } else if (is_null) {
+    result.set_null();
+  } else {
+    char *buf = static_cast<char*>(allocator->alloc(j_buf.length()));
+    if (OB_ISNULL(buf)) {
+      ret = OB_ALLOCATE_MEMORY_FAILED;
+      LOG_WARN("fail to alloc memory for json quote result", K(ret), K(j_buf.length()));
+    } else {
+      MEMCPY(buf, j_buf.ptr(), j_buf.length());
+      result.set_collation_type(result_type_.get_collation_type());
+      result.set_string(ObLongTextType, buf, j_buf.length());
+    }
+  }
+
+  return ret;
+}
+
+int ObExprJsonQuote::eval_json_quote(const ObExpr &expr, ObEvalCtx &ctx, ObDatum &res)
+{
+  INIT_SUCC(ret);
+  common::ObArenaAllocator &temp_allocator = ctx.get_reset_tmp_alloc();
+  ObJsonBuffer j_buf(&temp_allocator);
+  ObExpr *arg = expr.args_[0];
+  ObObjType type = arg->datum_meta_.type_;
+  ObCollationType cs_type = arg->datum_meta_.cs_type_;
+  ObDatum* json_datum = NULL;
+  bool is_null = false;
+
+  if (OB_FAIL(arg->eval(ctx, json_datum))) {
+    LOG_WARN("failed: eval json args datum.", K(ret));
+  } else if (OB_FAIL(calc(*json_datum, type, cs_type, j_buf, is_null))) {
+    LOG_WARN("fail to calc json quote result in new engine", K(ret), K(type));
+  } else if (is_null) {
+    res.set_null();
+  } else {
+    char *buf = expr.get_str_res_mem(ctx, j_buf.length());
+    if (OB_ISNULL(buf)) {
+      ret = OB_ALLOCATE_MEMORY_FAILED;
+      LOG_WARN("fail to alloc memory for json quote result", K(ret), K(j_buf.length()));
+    } else {
+      MEMCPY(buf, j_buf.ptr(), j_buf.length());
+      res.set_string(buf, j_buf.length());
+    }
+  }
+
+  return ret;
+}
+
+int ObExprJsonQuote::cg_expr(ObExprCGCtx &expr_cg_ctx, const ObRawExpr &raw_expr,
+                             ObExpr &rt_expr) const
+{
+  UNUSED(expr_cg_ctx);
+  UNUSED(raw_expr);
+  rt_expr.eval_func_ = eval_json_quote;
+  return OB_SUCCESS;
+}
+
+}
+}